\input texinfo    @c -*- texinfo -*-
@c %**start of header
@setfilename org.info
@settitle The Org Manual
@documentencoding UTF-8
@documentlanguage en
@set txicodequoteundirected
@set txicodequotebacktick
@set MAINTAINERSITE @uref{https://orgmode.org,maintainers webpage}
@set MAINTAINER Carsten Dominik
@set MAINTAINEREMAIL @email{carsten at orgmode dot org}
@set MAINTAINERCONTACT @uref{mailto:carsten at orgmode dot org,contact the maintainer}
@c %**end of header

@copying
This manual is for Org version 9.3.

Copyright @copyright{} 2004--2019  Free Software Foundation, Inc.

@quotation
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.3 or
any later version published by the Free Software Foundation; with no
Invariant Sections, with the Front-Cover Texts being ``A GNU Manual,''
and with the Back-Cover Texts as in (a) below.  A copy of the license
is included in the section entitled ``GNU Free Documentation License.''

(a) The FSF's Back-Cover Text is: ``You have the freedom to copy and
modify this GNU manual.''

@end quotation
@end copying

@dircategory Emacs
@direntry
* Org Mode: (org).      Outline-based notes management and organizer.
@end direntry

@finalout
@titlepage
@title The Org Manual
@subtitle Release 9.3
@author The Org Mode Developers
@page
@vskip 0pt plus 1filll
@insertcopying
@end titlepage

@contents

@ifnottex
@node Top
@top The Org Manual

@insertcopying
@end ifnottex

@menu
* Introduction::                 Getting started.
* Document Structure::           A tree works like your brain.
* Tables::                       Pure magic for quick formatting.
* Hyperlinks::                   Notes in context.
* TODO Items::                   Every tree branch can be a TODO item.
* Tags::                         Tagging headlines and matching sets of tags.
* Properties and Columns::       Storing information about an entry.
* Dates and Times::              Making items useful for planning.
* Refiling and Archiving::       Moving and copying information with ease.
* Capture and Attachments::      Dealing with external data.
* Agenda Views::                 Collecting information into views.
* Markup for Rich Contents::     Compose beautiful documents.
* Exporting::                    Sharing and publishing notes.
* Publishing::                   Create a web site of linked Org files.
* Working with Source Code::     Export, evaluate, and tangle code blocks.
* Miscellaneous::                All the rest which did not fit elsewhere.
* Hacking::                      How to hack your way around.
* History and Acknowledgments::  How Org came into being.
* GNU Free Documentation License:: The license for this documentation.
* Main Index::                   An index of Org's concepts and features.
* Key Index::                    Key bindings and where they are described.
* Command and Function Index::   Command names and some internal functions.
* Variable Index::               Variables mentioned in the manual.

@detailmenu
--- The Detailed Node Listing ---

Introduction

* Summary::                      Brief summary of what Org does.
* Installation::                 Installing Org.
* Activation::                   How to activate Org for certain buffers.
* Feedback::                     Bug reports, ideas, patches, etc.
* Conventions::                  Typesetting conventions used in this manual.

Document Structure

* Headlines::                    How to typeset Org tree headlines.
* Visibility Cycling::           Show and hide, much simplified.
* Motion::                       Jumping to other headlines.
* Structure Editing::            Changing sequence and level of headlines.
* Sparse Trees::                 Matches embedded in context.
* Plain Lists::                  Additional structure within an entry.
* Drawers::                      Tucking stuff away.
* Blocks::                       Folding blocks.

Visibility Cycling

* Global and local cycling::     Cycling through various visibility states.
* Initial visibility::           Setting the initial visibility state.
* Catching invisible edits::     Preventing mistakes when editing invisible parts.

Tables

* Built-in Table Editor::        Simple tables.
* Column Width and Alignment::   Overrule the automatic settings.
* Column Groups::                Grouping to trigger vertical lines.
* Orgtbl Mode::                  The table editor as minor mode.
* The Spreadsheet::              The table editor has spreadsheet capabilities.
* Org Plot::                     Plotting from Org tables.

The Spreadsheet

* References::                   How to refer to another field or range.
* Formula syntax for Calc::      Using Calc to compute stuff.
* Formula syntax for Lisp::      Writing formulas in Emacs Lisp.
* Durations and time values::    How to compute durations and time values.
* Field and range formulas::     Formula for specific (ranges of) fields.
* Column formulas::              Formulas valid for an entire column.
* Lookup functions::             Lookup functions for searching tables.
* Editing and debugging formulas:: Fixing formulas.
* Updating the table::           Recomputing all dependent fields.
* Advanced features::            Field and column names, automatic recalculation...

Hyperlinks

* Link Format::                  How links in Org are formatted.
* Internal Links::               Links to other places in the current file.
* Radio Targets::                Make targets trigger links in plain text.
* External Links::               URL-like links to the world.
* Handling Links::               Creating, inserting and following.
* Using Links Outside Org::      Linking from my C source code?
* Link Abbreviations::           Shortcuts for writing complex links.
* Search Options::               Linking to a specific location.
* Custom Searches::              When the default search is not enough.

TODO Items

* TODO Basics::                  Marking and displaying TODO entries.
* TODO Extensions::              Workflow and assignments.
* Progress Logging::             Dates and notes for progress.
* Priorities::                   Some things are more important than others.
* Breaking Down Tasks::          Splitting a task into manageable pieces.
* Checkboxes::                   Tick-off lists.

TODO Extensions

* Workflow states::              From TODO to DONE in steps.
* TODO types::                   I do this, Fred does the rest.
* Multiple sets in one file::    Mixing it all, still finding your way.
* Fast access to TODO states::   Single letter selection of state.
* Per-file keywords::            Different files, different requirements.
* Faces for TODO keywords::      Highlighting states.
* TODO dependencies::            When one task needs to wait for others.

Progress Logging

* Closing items::                When was this entry marked as done?
* Tracking TODO state changes::  When did the status change?
* Tracking your habits::         How consistent have you been?

Tags

* Tag Inheritance::              Tags use the tree structure of an outline.
* Setting Tags::                 How to assign tags to a headline.
* Tag Hierarchy::                Create a hierarchy of tags.
* Tag Searches::                 Searching for combinations of tags.

Properties and Columns

* Property Syntax::              How properties are spelled out.
* Special Properties::           Access to other Org mode features.
* Property Searches::            Matching property values.
* Property Inheritance::         Passing values down a tree.
* Column View::                  Tabular viewing and editing.

Column View

* Defining columns::             The COLUMNS format property.
* Using column view::            How to create and use column view.
* Capturing column view::        A dynamic block for column view.

Defining columns

* Scope of column definitions::  Where defined, where valid?
* Column attributes::            Appearance and content of a column.

Dates and Times

* Timestamps::                   Assigning a time to a tree entry.
* Creating Timestamps::          Commands to insert timestamps.
* Deadlines and Scheduling::     Planning your work.
* Clocking Work Time::           Tracking how long you spend on a task.
* Effort Estimates::             Planning work effort in advance.
* Timers::                       Notes with a running timer.

Creating Timestamps

* The date/time prompt::         How Org mode helps you enter dates and times.
* Custom time format::           Making dates look different.

Deadlines and Scheduling

* Inserting deadline/schedule::  Planning items.
* Repeated tasks::               Items that show up again and again.

Clocking Work Time

* Clocking commands::            Starting and stopping a clock.
* The clock table::              Detailed reports.
* Resolving idle time::          Resolving time when you've been idle.

Refiling and Archiving

* Refile and Copy::              Moving/copying a tree from one place to another.
* Archiving::                    What to do with finished products.

Archiving

* Moving subtrees::              Moving a tree to an archive file.
* Internal archiving::           Switch off a tree but keep it in the file.

Capture and Attachments

* Capture::                      Capturing new stuff.
* Attachments::                  Attach files to outlines.
* RSS Feeds::                    Getting input from RSS feeds.

Capture

* Setting up capture::           Where notes will be stored.
* Using capture::                Commands to invoke and terminate capture.
* Capture templates::            Define the outline of different note types.

Capture templates

* Template elements::            What is needed for a complete template entry.
* Template expansion::           Filling in information about time and context.
* Templates in contexts::        Only show a template in a specific context.

Attachments

* Attachment defaults and dispatcher:: How to access attachment commands
* Attachment options::           Configuring the attachment system
* Attachment links::             Hyperlink access to attachments
* Automatic version-control with Git:: Everything safely stored away
* Attach from Dired::            Using dired to select an attachment

Agenda Views

* Agenda Files::                 Files being searched for agenda information.
* Agenda Dispatcher::            Keyboard access to agenda views.
* Built-in Agenda Views::        What is available out of the box?
* Presentation and Sorting::     How agenda items are prepared for display.
* Agenda Commands::              Remote editing of Org trees.
* Custom Agenda Views::          Defining special searches and views.
* Exporting Agenda Views::       Writing a view to a file.
* Agenda Column View::           Using column view for collected entries.

Built-in Agenda Views

* Weekly/daily agenda::          The calendar page with current tasks.
* Global TODO list::             All unfinished action items.
* Matching tags and properties:: Structured information with fine-tuned search.
* Search view::                  Find entries by searching for text.
* Stuck projects::               Find projects you need to review.

Presentation and Sorting

* Categories::                   Not all tasks are equal.
* Time-of-day specifications::   How the agenda knows the time.
* Sorting of agenda items::      The order of things.
* Filtering/limiting agenda items:: Dynamically narrow the agenda.

Custom Agenda Views

* Storing searches::             Type once, use often.
* Block agenda::                 All the stuff you need in a single buffer.
* Setting options::              Changing the rules.

Markup for Rich Contents

* Paragraphs::                   The basic unit of text.
* Emphasis and Monospace::       Bold, italic, etc.
* Subscripts and Superscripts::  Simple syntax for raising/lowering text.
* Special Symbols::              Greek letters and other symbols.
* Embedded @LaTeX{}::            LaTeX can be freely used inside Org documents.
* Literal Examples::             Source code examples with special formatting.
* Images::                       Display an image.
* Captions::                     Describe tables, images...
* Horizontal Rules::             Make a line.
* Creating Footnotes::           Edit and read footnotes.

Embedded @LaTeX{}

* @LaTeX{} fragments::           Complex formulas made easy.
* Previewing @LaTeX{} fragments:: What will this snippet look like?
* CD@LaTeX{} mode::              Speed up entering of formulas.

Exporting

* The Export Dispatcher::        The main interface.
* Export Settings::              Common export settings.
* Table of Contents::            The if and where of the table of contents.
* Include Files::                Include additional files into a document.
* Macro Replacement::            Use macros to create templates.
* Comment Lines::                What will not be exported.
* ASCII/Latin-1/UTF-8 export::   Exporting to flat files with encoding.
* Beamer Export::                Producing presentations and slides.
* HTML Export::                  Exporting to HTML.
* @LaTeX{} Export::              Exporting to @LaTeX{} and processing to PDF.
* Markdown Export::              Exporting to Markdown.
* OpenDocument Text Export::     Exporting to OpenDocument Text.
* Org Export::                   Exporting to Org.
* Texinfo Export::               Exporting to Texinfo.
* iCalendar Export::             Exporting to iCalendar.
* Other Built-in Back-ends::     Exporting to a man page.
* Advanced Export Configuration:: Fine-tuning the export output.
* Export in Foreign Buffers::    Author tables and lists in Org syntax.

Beamer Export

* Beamer export commands::       For creating Beamer documents.
* Beamer specific export settings:: For customizing Beamer export.
* Frames and Blocks in Beamer::  For composing Beamer slides.
* Beamer specific syntax::       For using in Org documents.
* Editing support::              Editing support.
* A Beamer example::             A complete presentation.

HTML Export

* HTML export commands::         Invoking HTML export.
* HTML specific export settings:: Settings for HTML export.
* HTML doctypes::                Exporting various (X)HTML flavors.
* HTML preamble and postamble::  Inserting preamble and postamble.
* Quoting HTML tags::            Using direct HTML in Org files.
* Headlines in HTML export::     Formatting headlines.
* Links in HTML export::         Inserting and formatting links.
* Tables in HTML export::        How to modify the formatting of tables.
* Images in HTML export::        How to insert figures into HTML output.
* Math formatting in HTML export:: Beautiful math also on the web.
* Text areas in HTML export::    An alternate way to show an example.
* CSS support::                  Changing the appearance of the output.
* JavaScript support::           Info and folding in a web browser.

@LaTeX{} Export

* @LaTeX{}/PDF export commands:: For producing @LaTeX{} and PDF documents.
* @LaTeX{} specific export settings:: Unique to this @LaTeX{} back-end.
* @LaTeX{} header and sectioning:: Setting up the export file structure.
* Quoting @LaTeX{} code::        Incorporating literal @LaTeX{} code.
* Tables in @LaTeX{} export::    Options for exporting tables to @LaTeX{}.
* Images in @LaTeX{} export::    How to insert figures into @LaTeX{} output.
* Plain lists in @LaTeX{} export:: Attributes specific to lists.
* Source blocks in @LaTeX{} export:: Attributes specific to source code blocks.
* Example blocks in @LaTeX{} export:: Attributes specific to example blocks.
* Special blocks in @LaTeX{} export:: Attributes specific to special blocks.
* Horizontal rules in @LaTeX{} export:: Attributes specific to horizontal rules.

OpenDocument Text Export

* Pre-requisites for ODT export:: Required packages.
* ODT export commands::          Invoking export.
* ODT specific export settings:: Configuration options.
* Extending ODT export::         Producing DOC, PDF files.
* Applying custom styles::       Styling the output.
* Links in ODT export::          Handling and formatting links.
* Tables in ODT export::         Org tables conversions.
* Images in ODT export::         Inserting images.
* Math formatting in ODT export:: Formatting @LaTeX{} fragments.
* Labels and captions in ODT export:: Rendering objects.
* Literal examples in ODT export:: For source code and example blocks.
* Advanced topics in ODT export:: For power users.

Math formatting in ODT export

* @LaTeX{} math snippets::       Embedding in @LaTeX{} format.
* MathML and OpenDocument formula files:: Embedding in native format.

Texinfo Export

* Texinfo export commands::      Invoking commands.
* Texinfo specific export settings:: Setting the environment.
* Texinfo file header::          Generating the header.
* Texinfo title and copyright page:: Creating preamble pages.
* Info directory file::          Installing a manual in Info file hierarchy.
* Headings and sectioning structure:: Building document structure.
* Indices::                      Creating indices.
* Quoting Texinfo code::         Incorporating literal Texinfo code.
* Plain lists in Texinfo export:: List attributes.
* Tables in Texinfo export::     Table attributes.
* Images in Texinfo export::     Image attributes.
* Quotations in Texinfo export:: Quote block attributes.
* Special blocks in Texinfo export:: Special block attributes.
* A Texinfo example::            Processing Org to Texinfo.

Publishing

* Configuration::                Defining projects.
* Uploading Files::              How to get files up on the server.
* Sample Configuration::         Example projects.
* Triggering Publication::       Publication commands.

Configuration

* Project alist::                The central configuration variable.
* Sources and destinations::     From here to there.
* Selecting files::              What files are part of the project?
* Publishing action::            Setting the function doing the publishing.
* Publishing options::           Tweaking HTML/@LaTeX{} export.
* Publishing links::             Which links keep working after publishing?
* Site map::                     Generating a list of all pages.
* Generating an index::          An index that reaches across pages.

Sample Configuration

* Simple example::               One-component publishing.
* Complex example::              A multi-component publishing example.

Working with Source Code

* Structure of Code Blocks::     Code block syntax described.
* Using Header Arguments::       Different ways to set header arguments.
* Environment of a Code Block::  Arguments, sessions, working directory...
* Evaluating Code Blocks::       Place results of evaluation in the Org buffer.
* Results of Evaluation::        Choosing a results type, post-processing...
* Exporting Code Blocks::        Export contents and/or results.
* Extracting Source Code::       Create pure source code files.
* Languages::                    List of supported code block languages.
* Editing Source Code::          Language major-mode editing.
* Noweb Reference Syntax::       Literate programming in Org mode.
* Library of Babel::             Use and contribute to a library of useful code blocks.
* Key bindings and Useful Functions:: Work quickly with code blocks.
* Batch Execution::              Call functions from the command line.

Miscellaneous

* Completion::                   @kbd{M-@key{TAB}} guesses completions.
* Structure Templates::          Quick insertion of structural elements.
* Speed Keys::                   Electric commands at the beginning of a headline.
* Clean View::                   Getting rid of leading stars in the outline.
* Dynamic Headline Numbering::   Display and update outline numbering.
* The Very Busy @kbd{C-c C-c} Key:: When in doubt, press @kbd{C-c C-c}.
* In-buffer Settings::           Overview of keywords.
* Org Syntax::                   Formal description of Org's syntax.
* Documentation Access::         Read documentation about current syntax.
* Escape Character::
* Code Evaluation Security::     Org files evaluate in-line code.
* Interaction::                  With other Emacs packages.
* TTY Keys::                     Using Org on a tty.
* Protocols::                    External access to Emacs and Org.
* Org Crypt::                    Encrypting Org files.
* Org Mobile::                   Viewing and capture on a mobile device.

Clean View

* Org Indent Mode::
* Hard indentation::

Interaction

* Cooperation::                  Packages Org cooperates with.
* Conflicts::                    Packages that lead to conflicts.

Protocols

* The @code{store-link} protocol:: Store a link, push URL to kill-ring.
* The @code{capture} protocol::  Fill a buffer with external information.
* The @code{open-source} protocol:: Edit published contents.

Org Mobile

* Setting up the staging area::  For the mobile device.
* Pushing to the mobile application:: Uploading Org files and agendas.
* Pulling from the mobile application:: Integrating captured and flagged items.

Hacking

* Hooks: Hooks (2).              How to reach into Org's internals.
* Add-on Packages::              Available extensions.
* Adding Hyperlink Types::       New custom link types.
* Adding Export Back-ends::      How to write new export back-ends.
* Tables in Arbitrary Syntax::   Orgtbl for LaTeX and other programs.
* Dynamic Blocks::               Automatically filled blocks.
* Special Agenda Views::         Customized views.
* Speeding Up Your Agendas::     Tips on how to speed up your agendas.
* Extracting Agenda Information:: Post-processing agenda information.
* Using the Property API::       Writing programs that use entry properties.
* Using the Mapping API::        Mapping over all or selected entries.

Tables in Arbitrary Syntax

* Radio tables::                 Sending and receiving radio tables.
* A @LaTeX{} example::           Step by step, almost a tutorial.
* Translator functions::         Copy and modify.

@end detailmenu
@end menu

@node Introduction
@chapter Introduction

@cindex introduction

@menu
* Summary::                      Brief summary of what Org does.
* Installation::                 Installing Org.
* Activation::                   How to activate Org for certain buffers.
* Feedback::                     Bug reports, ideas, patches, etc.
* Conventions::                  Typesetting conventions used in this manual.
@end menu

@node Summary
@section Summary

@cindex summary

Org is a mode for keeping notes, maintaining TODO lists, and project
planning with a fast and effective plain-text markup language.  It
also is an authoring system with unique support for literate
programming and reproducible research.

Org is implemented on top of Outline mode, which makes it possible to
keep the content of large files well structured.  Visibility cycling
and structure editing help to work with the tree.  Tables are easily
created with a built-in table editor.  Plain text URL-like links
connect to websites, emails, Usenet messages, BBDB entries, and any
files related to the projects.

Org develops organizational tasks around notes files that contain
lists or information about projects as plain text.  Project planning
and task management make use of metadata which is part of an outline
node.  Based on this data, specific entries can be extracted in
queries and create dynamic @emph{agenda views} that also integrate the
Emacs calendar and diary.  Org can be used to implement many different
project planning schemes, such as David Allen's GTD system.

Org files can serve as a single source authoring system with export to
many different formats such as HTML, @LaTeX{}, Open Document, and
Markdown.  New export backends can be derived from existing ones, or
defined from scratch.

Org files can include source code blocks, which makes Org uniquely
suited for authoring technical documents with code examples. Org
source code blocks are fully functional; they can be evaluated in
place and their results can be captured in the file.  This makes it
possible to create a single file reproducible research compendium.

Org keeps simple things simple.  When first fired up, it should feel
like a straightforward, easy to use outliner.  Complexity is not
imposed, but a large amount of functionality is available when needed.
Org is a toolbox.  Many users actually run only a---very
personal---fraction of Org's capabilities, and know that there is more
whenever they need it.

All of this is achieved with strictly plain text files, the most
portable and future-proof file format.  Org runs in Emacs.  Emacs is
one of the most widely ported programs, so that Org mode is available
on every major platform.

@cindex FAQ
There is a website for Org which provides links to the newest version
of Org, as well as additional information, frequently asked questions
(FAQ), links to tutorials, etc.  This page is located at
@uref{https://orgmode.org}.

@cindex print edition
An earlier version (7.3) of this manual is available as a @uref{http://www.network-theory.co.uk/org/manual/, paperback
book from Network Theory Ltd.}.

@node Installation
@section Installation

@cindex installation

Org is included in all recent distributions of GNU Emacs, so you
probably do not need to install it.  Most users will simply activate
Org and begin exploring its many features.

If, for one reason or another, you want to install Org on top of this
pre-packaged version, there are three ways to do it:

@itemize
@item
by using the Emacs package system;
@item
by downloading Org as an archive; or
@item
by using Org's git repository.
@end itemize

We @strong{strongly recommend} sticking to a single installation method.

@anchor{Using Emacs packaging system}
@subheading Using Emacs packaging system

Recent Emacs distributions include a packaging system which lets you
install Elisp libraries.  You can install Org with @kbd{M-x package-install @key{RET} org}.

@quotation Important
You need to do this in a session where no @samp{.org} file has been
visited, i.e., where no Org built-in function have been loaded.
Otherwise autoload Org functions will mess up the installation.

@end quotation

If you want to use Org's package repository, check out the @uref{https://orgmode.org/elpa.html, Org ELPA
page}.

@anchor{Downloading Org as an archive}
@subheading Downloading Org as an archive

You can download Org latest release from @uref{https://orgmode.org/, Org's website}.  In this case,
make sure you set the load-path correctly in your Emacs init file:

@lisp
(add-to-list 'load-path "~/path/to/orgdir/lisp")
@end lisp

The downloaded archive contains contributed libraries that are not
included in Emacs.  If you want to use them, add the @samp{contrib/}
directory to your load-path:

@lisp
(add-to-list 'load-path "~/path/to/orgdir/contrib/lisp" t)
@end lisp

Optionally, you can compile the files and/or install them in your
system.  Run @samp{make help} to list compilation and installation options.

@anchor{Using Org's git repository}
@subheading Using Org's git repository

You can clone Org's repository and install Org like this:

@example
$ cd ~/src/
$ git clone git@@code.orgmode.org:bzg/org-mode.git
$ cd org-mode/
$ make autoloads
@end example

Note that in this case, @samp{make autoloads} is mandatory: it defines
Org's version in @samp{org-version.el} and Org's autoloads in
@samp{org-loaddefs.el}.

Remember to add the correct load-path as described in the method
above.

You can also compile with @samp{make}, generate the documentation with
@samp{make doc}, create a local configuration with @samp{make config} and
install Org with @samp{make install}.  Please run @samp{make help} to get the
list of compilation/installation options.

For more detailed explanations on Org's build system, please check the
Org Build System page on @uref{https://orgmode.org/worg/dev/org-build-system.html, Worg}.

@node Activation
@section Activation

@cindex activation
@cindex autoload
@cindex ELPA
@cindex global key bindings
@cindex key bindings, global

Org mode buffers need Font Lock to be turned on: this is the default
in Emacs@footnote{If you do not use Font Lock globally turn it on in Org buffer
with @samp{(add-hook 'org-mode-hook 'turn-on-font-lock)}.}.

There are compatibility issues between Org mode and some other Elisp
packages (see @ref{Conflicts}).  Please take the
time to check the list.

@findex org-agenda
@findex org-capture
@findex org-store-link
For a better experience, the three Org commands @code{org-store-link},
@code{org-capture} and @code{org-agenda} ought to be accessible anywhere in
Emacs, not just in Org buffers.  To that effect, you need to bind them
to globally available keys, like the ones reserved for users (see
@ref{Key Binding Conventions,,,elisp,}).  Here are suggested bindings,
please modify the keys to your own liking.

@lisp
(global-set-key (kbd "C-c l") 'org-store-link)
(global-set-key (kbd "C-c a") 'org-agenda)
(global-set-key (kbd "C-c c") 'org-capture)
@end lisp

@cindex Org mode, turning on
Files with the @samp{.org} extension use Org mode by default.  To turn on
Org mode in a file that does not have the extension @samp{.org}, make the
first line of a file look like this:

@example
MY PROJECTS    -*- mode: org; -*-
@end example


@vindex org-insert-mode-line-in-empty-file
@noindent
which selects Org mode for this buffer no matter what the file's name
is.  See also the variable @code{org-insert-mode-line-in-empty-file}.

Many commands in Org work on the region if the region is @emph{active}.  To
make use of this, you need to have Transient Mark mode turned on,
which is the default.  If you do not like it, you can create an active
region by using the mouse to select a region, or pressing
@kbd{C-@key{SPC}} twice before moving point.

@node Feedback
@section Feedback

@cindex feedback
@cindex bug reports
@cindex reporting a bug
@cindex maintainer
@cindex author

If you find problems with Org, or if you have questions, remarks, or
ideas about it, please send an email to the Org mailing list
@email{emacs-orgmode@@gnu.org}.  You can subscribe to the list @uref{https://lists.gnu.org/mailman/listinfo/emacs-orgmode, from this
web page}.  If you are not a member of the mailing list, your mail will
be passed to the list after a moderator has approved it@footnote{Please consider subscribing to the mailing list in order to
minimize the work the mailing list moderators have to do.}.

@findex org-version
@findex org-submit-bug-report
For bug reports, please first try to reproduce the bug with the latest
version of Org available---if you are running an outdated version, it
is quite possible that the bug has been fixed already.  If the bug
persists, prepare a report and provide as much information as
possible, including the version information of Emacs (@kbd{M-x emacs-version}) and Org (@kbd{M-x org-version}), as well as
the Org related setup in the Emacs init file.  The easiest way to do
this is to use the command

@example
M-x org-submit-bug-report <RET>
@end example


@noindent
which puts all this information into an Emacs mail buffer so that you
only need to add your description.  If you are not sending the Email
from within Emacs, please copy and paste the content into your Email
program.

Sometimes you might face a problem due to an error in your Emacs or
Org mode setup.  Before reporting a bug, it is very helpful to start
Emacs with minimal customizations and reproduce the problem.  Doing so
often helps you determine if the problem is with your customization or
with Org mode itself.  You can start a typical minimal session with
a command like the example below.

@example
$ emacs -Q -l /path/to/minimal-org.el
@end example


However if you are using Org mode as distributed with Emacs, a minimal
setup is not necessary.  In that case it is sufficient to start Emacs
as @samp{emacs -Q}.  The @samp{minimal-org.el} setup file can have contents as
shown below.

@lisp
;;; Minimal setup to load latest `org-mode'.

;; Activate debugging.
(setq debug-on-error t
      debug-on-signal nil
      debug-on-quit nil)

;; Add latest Org mode to load path.
(add-to-list 'load-path (expand-file-name "/path/to/org-mode/lisp"))
(add-to-list 'load-path (expand-file-name "/path/to/org-mode/contrib/lisp" t))
@end lisp

If an error occurs, a ``backtrace'' can be very useful---see below on
how to create one.  Often a small example file helps, along with clear
information about:

@enumerate
@item
What exactly did you do?
@item
What did you expect to happen?
@item
What happened instead?
@end enumerate

Thank you for helping to improve this program.

@anchor{How to create a useful backtrace}
@subheading How to create a useful backtrace

@cindex backtrace of an error
If working with Org produces an error with a message you do not
understand, you may have hit a bug.  The best way to report this is by
providing, in addition to what was mentioned above, a backtrace.  This
is information from the built-in debugger about where and how the
error occurred.  Here is how to produce a useful backtrace:

@enumerate
@item
Reload uncompiled versions of all Org mode Lisp files.  The
backtrace contains much more information if it is produced with
uncompiled code.  To do this, use

@example
C-u M-x org-reload <RET>
@end example


@noindent
or, from the menu: Org @arrow{} Refresh/Reload @arrow{} Reload Org uncompiled.

@item
Then, activate the debugger:

@example
M-x toggle-debug-or-error <RET>
@end example


@noindent
or, from the menu: Options @arrow{} Enter Debugger on Error.

@item
Do whatever you have to do to hit the error.  Do not forget to
document the steps you take.

@item
When you hit the error, a @samp{*Backtrace*} buffer appears on the
screen.  Save this buffer to a file---for example using @kbd{C-x C-w}---and attach it to your bug report.
@end enumerate

@node Conventions
@section Typesetting Conventions Used in this Manual



@anchor{TODO keywords tags properties etc}
@subheading TODO keywords, tags, properties, etc.

Org uses various syntactical elements: TODO keywords, tags, property
names, keywords, blocks, etc.  In this manual we use the following
conventions:

@table @asis
@item @samp{TODO}
@itemx @samp{WAITING}
TODO keywords are written with all capitals, even if they are
user-defined.

@item @samp{boss}
@itemx @samp{ARCHIVE}
Tags are case-sensitive.  User-defined tags are written in
lowercase; built-in tags with special meaning are written as they
should appear in the document, usually with all capitals.

@item @samp{Release}
@itemx @samp{PRIORITY}
User-defined properties are capitalized; built-in properties with
special meaning are written with all capitals.

@item @samp{TITLE}
@itemx @samp{BEGIN} @dots{} @samp{END}
Keywords and blocks are written in uppercase to enhance their
readability, but you can use lowercase in your Org files.
@end table

@anchor{Key bindings and commands}
@subheading Key bindings and commands

The manual lists both the keys and the corresponding commands for
accessing a functionality.  Org mode often uses the same key for
different functions, depending on context.  The command that is bound
to such keys has a generic name, like @code{org-metaright}.  In the manual
we will, wherever possible, give the function that is internally
called by the generic command.  For example, in the chapter on
document structure, @kbd{M-@key{RIGHT}} will be listed to call
@code{org-do-demote}, while in the chapter on tables, it will be listed to
call @code{org-table-move-column-right}.

@node Document Structure
@chapter Document Structure

@cindex document structure
@cindex structure of document
Org is an outliner.  Outlines allow a document to be organized in
a hierarchical structure, which, least for me, is the best
representation of notes and thoughts.  An overview of this structure
is achieved by folding, i.e., hiding large parts of the document to
show only the general document structure and the parts currently being
worked on.  Org greatly simplifies the use of outlines by compressing
the entire show and hide functionalities into a single command,
@code{org-cycle}, which is bound to the @kbd{@key{TAB}} key.

@menu
* Headlines::                    How to typeset Org tree headlines.
* Visibility Cycling::           Show and hide, much simplified.
* Motion::                       Jumping to other headlines.
* Structure Editing::            Changing sequence and level of headlines.
* Sparse Trees::                 Matches embedded in context.
* Plain Lists::                  Additional structure within an entry.
* Drawers::                      Tucking stuff away.
* Blocks::                       Folding blocks.
@end menu

@node Headlines
@section Headlines

@cindex headlines
@cindex outline tree
@vindex org-special-ctrl-a/e
@vindex org-special-ctrl-k
@vindex org-ctrl-k-protect-subtree

Headlines define the structure of an outline tree.  The headlines in
Org start with one or more stars, on the left margin@footnote{See the variables @code{org-special-ctrl-a/e}, @code{org-special-ctrl-k},
and @code{org-ctrl-k-protect-subtree} to configure special behavior of
@kbd{C-a}, @kbd{C-e}, and @kbd{C-k} in headlines.  Note
also that clocking only works with headings indented less than 30
stars.}.  For
example:

@example
* Top level headline
** Second level
*** Third level
    some text
*** Third level
    more text
* Another top level headline
@end example

@vindex org-footnote-section
The name defined in @code{org-footnote-section} is reserved.  Do not use it
as a title for your own headings.

Some people find the many stars too noisy and would prefer an outline
that has whitespace followed by a single star as headline starters.
This can be achieved using a Org Indent minor mode.  See @ref{Clean View} for more information.

Headlines are not numbered.  However, you may want to dynamically
number some, or all, of them.  See @ref{Dynamic Headline Numbering}.

@vindex org-cycle-separator-lines
An empty line after the end of a subtree is considered part of it and
is hidden when the subtree is folded.  However, if you leave at least
two empty lines, one empty line remains visible after folding the
subtree, in order to structure the collapsed view.  See the variable
@code{org-cycle-separator-lines} to modify this behavior.

@node Visibility Cycling
@section Visibility Cycling

@cindex cycling, visibility
@cindex visibility cycling
@cindex trees, visibility
@cindex show hidden text
@cindex hide text

@menu
* Global and local cycling::     Cycling through various visibility states.
* Initial visibility::           Setting the initial visibility state.
* Catching invisible edits::     Preventing mistakes when editing invisible parts.
@end menu

@node Global and local cycling
@subsection Global and local cycling

@cindex subtree visibility states
@cindex subtree cycling
@cindex folded, subtree visibility state
@cindex children, subtree visibility state
@cindex subtree, subtree visibility state

Outlines make it possible to hide parts of the text in the buffer.
Org uses just two commands, bound to @kbd{@key{TAB}} and
@kbd{S-@key{TAB}} to change the visibility in the buffer.

@table @asis
@item @kbd{@key{TAB}} (@code{org-cycle})
@kindex TAB
@findex org-cycle
@emph{Subtree cycling}: Rotate current subtree among the states

@example
,-> FOLDED -> CHILDREN -> SUBTREE --.
'-----------------------------------'
@end example

@vindex org-cycle-emulate-tab
Point must be on a headline for this to work@footnote{See, however, the option @code{org-cycle-emulate-tab}.}.

@item @kbd{S-@key{TAB}} (@code{org-global-cycle})
@itemx @kbd{C-u @key{TAB}}
@cindex global visibility states
@cindex global cycling
@cindex overview, global visibility state
@cindex contents, global visibility state
@cindex show all, global visibility state
@kindex C-u TAB
@kindex S-TAB
@findex org-global-cycle
@emph{Global cycling}: Rotate the entire buffer among the states

@example
,-> OVERVIEW -> CONTENTS -> SHOW ALL --.
'--------------------------------------'
@end example

When @kbd{S-@key{TAB}} is called with a numeric prefix argument N,
the CONTENTS view up to headlines of level N are shown.  Note that
inside tables (see @ref{Tables}), @kbd{S-@key{TAB}} jumps to the previous
field instead.

@vindex org-cycle-global-at-bob
You can run global cycling using @kbd{@key{TAB}} only if point is at
the very beginning of the buffer, but not on a headline, and
@code{org-cycle-global-at-bob} is set to a non-@code{nil} value.

@item @kbd{C-u C-u @key{TAB}} (@code{org-set-startup-visibility})
@cindex startup visibility
@kindex C-u C-u TAB
@findex org-set-startup-visibility
Switch back to the startup visibility of the buffer (see @ref{Initial visibility}).

@item @kbd{C-u C-u C-u @key{TAB}} (@code{outline-show-all})
@cindex show all, command
@kindex C-u C-u C-u TAB
@findex outline-show-all
Show all, including drawers.

@item @kbd{C-c C-r} (@code{org-reveal})
@cindex revealing context
@kindex C-c C-r
@findex org-reveal
Reveal context around point, showing the current entry, the
following heading and the hierarchy above.  Useful for working near
a location that has been exposed by a sparse tree command (see
@ref{Sparse Trees}) or an agenda command (see @ref{Agenda Commands}).  With a prefix argument show, on each level, all sibling
headings.  With a double prefix argument, also show the entire
subtree of the parent.

@item @kbd{C-c C-k} (@code{outline-show-branches})
@cindex show branches, command
@kindex C-c C-k
@findex outline-show-branches
Expose all the headings of the subtree, CONTENTS view for just one
subtree.

@item @kbd{C-c @key{TAB}} (@code{outline-show-children})
@cindex show children, command
@kindex C-c TAB
@findex outline-show-children
Expose all direct children of the subtree.  With a numeric prefix
argument N, expose all children down to level N@.

@item @kbd{C-c C-x b} (@code{org-tree-to-indirect-buffer})
@kindex C-c C-x b
@findex org-tree-to-indirect-buffer
Show the current subtree in an indirect buffer@footnote{The indirect buffer contains the entire buffer, but is narrowed
to the current tree.  Editing the indirect buffer also changes the
original buffer, but without affecting visibility in that buffer.  For
more information about indirect buffers, see @ref{Indirect Buffers,GNU Emacs Manual,,emacs,}.}.  With
a numeric prefix argument, N, go up to level N and then take that
tree.  If N is negative then go up that many levels.  With
a @kbd{C-u} prefix, do not remove the previously used indirect
buffer.

@item @kbd{C-c C-x v} (@code{org-copy-visible})
@kindex C-c C-x v
@findex org-copy-visible
Copy the @emph{visible} text in the region into the kill ring.
@end table

@node Initial visibility
@subsection Initial visibility

@vindex org-startup-folded
When Emacs first visits an Org file, the global state is set to
OVERVIEW, i.e., only the top level headlines are visible@footnote{When @code{org-agenda-inhibit-startup} is non-@code{nil}, Org does not
honor the default visibility state when first opening a file for the
agenda (see @ref{Speeding Up Your Agendas}).}.  This
can be configured through the variable @code{org-startup-folded}, or on
a per-file basis by adding one of the following lines anywhere in the
buffer:

@cindex @samp{STARTUP}, keyword
@example
#+STARTUP: overview
#+STARTUP: content
#+STARTUP: showall
#+STARTUP: showeverything
@end example

@cindex @samp{VISIBILITY}, property
Furthermore, any entries with a @samp{VISIBILITY} property (see @ref{Properties and Columns}) get their visibility adapted accordingly.  Allowed values
for this property are @samp{folded}, @samp{children}, @samp{content}, and @samp{all}.

@table @asis
@item @kbd{C-u C-u @key{TAB}} (@code{org-set-startup-visibility})
@kindex C-u C-u TAB
@findex org-set-startup-visibility
Switch back to the startup visibility of the buffer, i.e., whatever
is requested by startup options and @samp{VISIBILITY} properties in
individual entries.
@end table

@node Catching invisible edits
@subsection Catching invisible edits

@cindex edits, catching invisible

@vindex org-catch-invisible-edits
Sometimes you may inadvertently edit an invisible part of the buffer
and be confused on what has been edited and how to undo the mistake.
Setting @code{org-catch-invisible-edits} to non-@code{nil} helps preventing
this.  See the docstring of this option on how Org should catch
invisible edits and process them.

@node Motion
@section Motion

@cindex motion, between headlines
@cindex jumping, to headlines
@cindex headline navigation

The following commands jump to other headlines in the buffer.

@table @asis
@item @kbd{C-c C-n} (@code{org-next-visible-heading})
@kindex C-c C-n
@findex org-next-visible-heading
Next heading.

@item @kbd{C-c C-p} (@code{org-previous-visible-heading})
@kindex C-c C-p
@findex org-previous-visible-heading
Previous heading.

@item @kbd{C-c C-f} (@code{org-forward-heading-same-level})
@kindex C-c C-f
@findex org-forward-heading-same-level
Next heading same level.

@item @kbd{C-c C-b} (@code{org-backward-heading-same-level})
@kindex C-c C-b
@findex org-backward-heading-same-level
Previous heading same level.

@item @kbd{C-c C-u} (@code{outline-up-heading})
@kindex C-c C-u
@findex outline-up-heading
Backward to higher level heading.

@item @kbd{C-c C-j} (@code{org-goto})
@kindex C-c C-j
@findex org-goto
@vindex org-goto-auto-isearch
Jump to a different place without changing the current outline
visibility.  Shows the document structure in a temporary buffer,
where you can use the following keys to find your destination:

@multitable @columnfractions 0.3 0.7
@item @kbd{@key{TAB}}
@tab Cycle visibility.
@item @kbd{@key{DOWN}} / @kbd{@key{UP}}
@tab Next/previous visible headline.
@item @kbd{@key{RET}}
@tab Select this location.
@item @kbd{/}
@tab Do a Sparse-tree search
@end multitable

@noindent
The following keys work if you turn off @code{org-goto-auto-isearch}

@multitable @columnfractions 0.3 0.7
@item @kbd{n} / @kbd{p}
@tab Next/previous visible headline.
@item @kbd{f} / @kbd{b}
@tab Next/previous headline same level.
@item @kbd{u}
@tab One level up.
@item @kbd{0} @dots{} @kbd{9}
@tab Digit argument.
@item @kbd{q}
@tab Quit.
@end multitable

@vindex org-goto-interface
@noindent
See also the variable @code{org-goto-interface}.
@end table

@node Structure Editing
@section Structure Editing

@cindex structure editing
@cindex headline, promotion and demotion
@cindex promotion, of subtrees
@cindex demotion, of subtrees
@cindex subtree, cut and paste
@cindex pasting, of subtrees
@cindex cutting, of subtrees
@cindex copying, of subtrees
@cindex sorting, of subtrees
@cindex subtrees, cut and paste

@table @asis
@item @kbd{M-@key{RET}} (@code{org-meta-return})
@kindex M-RET
@findex org-meta-return
@vindex org-M-RET-may-split-line
Insert a new heading, item or row.

If the command is used at the @emph{beginning} of a line, and if there is
a heading or a plain list item (see @ref{Plain Lists}) at point, the new
heading/item is created @emph{before} the current line.  When used at the
beginning of a regular line of text, turn that line into a heading.

When this command is used in the middle of a line, the line is split
and the rest of the line becomes the new item or headline.  If you
do not want the line to be split, customize
@code{org-M-RET-may-split-line}.

Calling the command with a @kbd{C-u} prefix unconditionally
inserts a new heading at the end of the current subtree, thus
preserving its contents.  With a double @kbd{C-u C-u} prefix,
the new heading is created at the end of the parent subtree instead.

@item @kbd{C-@key{RET}} (@code{org-insert-heading-respect-content})
@kindex C-RET
@findex org-insert-heading-respect-content
Insert a new heading at the end of the current subtree.

@item @kbd{M-S-@key{RET}} (@code{org-insert-todo-heading})
@kindex M-S-RET
@findex org-insert-todo-heading
@vindex org-treat-insert-todo-heading-as-state-change
Insert new TODO entry with same level as current heading.  See also
the variable @code{org-treat-insert-todo-heading-as-state-change}.

@item @kbd{C-S-@key{RET}} (@code{org-insert-todo-heading-respect-content})
@kindex C-S-RET
@findex org-insert-todo-heading-respect-content
Insert new TODO entry with same level as current heading.  Like
@kbd{C-@key{RET}}, the new headline is inserted after the current
subtree.

@item @kbd{@key{TAB}} (@code{org-cycle})
@kindex TAB
@findex org-cycle
In a new entry with no text yet, the first @kbd{@key{TAB}} demotes
the entry to become a child of the previous one.  The next
@kbd{@key{TAB}} makes it a parent, and so on, all the way to top
level.  Yet another @kbd{@key{TAB}}, and you are back to the initial
level.

@item @kbd{M-@key{LEFT}} (@code{org-do-promote})
@kindex M-LEFT
@findex org-do-promote
Promote current heading by one level.

@item @kbd{M-@key{RIGHT}} (@code{org-do-demote})
@kindex M-RIGHT
@findex org-do-demote
Demote current heading by one level.

@item @kbd{M-S-@key{LEFT}} (@code{org-promote-subtree})
@kindex M-S-LEFT
@findex org-promote-subtree
Promote the current subtree by one level.

@item @kbd{M-S-@key{RIGHT}} (@code{org-demote-subtree})
@kindex M-S-RIGHT
@findex org-demote-subtree
Demote the current subtree by one level.

@item @kbd{M-@key{UP}} (@code{org-move-subtree-up})
@kindex M-UP
@findex org-move-subtree-up
Move subtree up, i.e., swap with previous subtree of same level.

@item @kbd{M-@key{DOWN}} (@code{org-move-subtree-down})
@kindex M-DOWN
@findex org-move-subtree-down
Move subtree down, i.e., swap with next subtree of same level.

@item @kbd{C-c @@} (@code{org-mark-subtree})
@kindex C-c @@
@findex org-mark-subtree
Mark the subtree at point.  Hitting repeatedly marks subsequent
subtrees of the same level as the marked subtree.

@item @kbd{C-c C-x C-w} (@code{org-cut-subtree})
@kindex C-c C-x C-w
@findex org-cut-subtree
Kill subtree, i.e., remove it from buffer but save in kill ring.
With a numeric prefix argument N, kill N sequential subtrees.

@item @kbd{C-c C-x M-w} (@code{org-copy-subtree})
@kindex C-c C-x M-w
@findex org-copy-subtree
Copy subtree to kill ring.  With a numeric prefix argument N, copy
the N sequential subtrees.

@item @kbd{C-c C-x C-y} (@code{org-paste-subtree})
@kindex C-c C-x C-y
@findex org-paste-subtree
Yank subtree from kill ring.  This does modify the level of the
subtree to make sure the tree fits in nicely at the yank position.
The yank level can also be specified with a numeric prefix argument,
or by yanking after a headline marker like @samp{****}.

@item @kbd{C-y} (@code{org-yank})
@kindex C-y
@findex org-yank
@vindex org-yank-adjusted-subtrees
@vindex org-yank-folded-subtrees
Depending on the variables @code{org-yank-adjusted-subtrees} and
@code{org-yank-folded-subtrees}, Org's internal @code{yank} command pastes
subtrees folded and in a clever way, using the same command as
@kbd{C-c C-x C-y}.  With the default settings, no level
adjustment takes place, but the yanked tree is folded unless doing
so would swallow text previously visible.  Any prefix argument to
this command forces a normal @code{yank} to be executed, with the prefix
passed along.  A good way to force a normal yank is @kbd{C-u C-y}.  If you use @code{yank-pop} after a yank, it yanks previous kill
items plainly, without adjustment and folding.

@item @kbd{C-c C-x c} (@code{org-clone-subtree-with-time-shift})
@kindex C-c C-x c
@findex org-clone-subtree-with-time-shift
Clone a subtree by making a number of sibling copies of it.  You are
prompted for the number of copies to make, and you can also specify
if any timestamps in the entry should be shifted.  This can be
useful, for example, to create a number of tasks related to a series
of lectures to prepare.  For more details, see the docstring of the
command @code{org-clone-subtree-with-time-shift}.

@item @kbd{C-c C-w} (@code{org-refile})
@kindex C-c C-w
@findex org-refile
Refile entry or region to a different location.  See @ref{Refile and Copy}.

@item @kbd{C-c ^} (@code{org-sort})
@kindex C-c ^
@findex org-sort
Sort same-level entries.  When there is an active region, all
entries in the region are sorted.  Otherwise the children of the
current headline are sorted.  The command prompts for the sorting
method, which can be alphabetically, numerically, by time---first
timestamp with active preferred, creation time, scheduled time,
deadline time---by priority, by TODO keyword---in the sequence the
keywords have been defined in the setup---or by the value of
a property.  Reverse sorting is possible as well.  You can also
supply your own function to extract the sorting key.  With
a @kbd{C-u} prefix, sorting is case-sensitive.

@item @kbd{C-x n s} (@code{org-narrow-to-subtree})
@kindex C-x n s
@findex org-narrow-to-subtree
Narrow buffer to current subtree.

@item @kbd{C-x n b} (@code{org-narrow-to-block})
@kindex C-x n b
@findex org-narrow-to-block
Narrow buffer to current block.

@item @kbd{C-x n w} (@code{widen})
@kindex C-x n w
@findex widen
Widen buffer to remove narrowing.

@item @kbd{C-c *} (@code{org-toggle-heading})
@kindex C-c *
@findex org-toggle-heading
Turn a normal line or plain list item into a headline---so that it
becomes a subheading at its location.  Also turn a headline into
a normal line by removing the stars.  If there is an active region,
turn all lines in the region into headlines.  If the first line in
the region was an item, turn only the item lines into headlines.
Finally, if the first line is a headline, remove the stars from all
headlines in the region.
@end table

@cindex region, active
@cindex active region
@cindex transient mark mode
When there is an active region---i.e., when Transient Mark mode is
active---promotion and demotion work on all headlines in the region.
To select a region of headlines, it is best to place both point and
mark at the beginning of a line, mark at the beginning of the first
headline, and point at the line just after the last headline to
change.  Note that when point is inside a table (see @ref{Tables}), the
Meta-Cursor keys have different functionality.

@node Sparse Trees
@section Sparse Trees

@cindex sparse trees
@cindex trees, sparse
@cindex folding, sparse trees
@cindex occur, command

@vindex org-show-context-detail
An important feature of Org mode is the ability to construct @emph{sparse
trees} for selected information in an outline tree, so that the entire
document is folded as much as possible, but the selected information
is made visible along with the headline structure above it@footnote{See also the variable @code{org-show-context-detail} to decide how
much context is shown around each match.}.
Just try it out and you will see immediately how it works.

Org mode contains several commands creating such trees, all these
commands can be accessed through a dispatcher:

@table @asis
@item @kbd{C-c /} (@code{org-sparse-tree})
@kindex C-c /
@findex org-sparse-tree
This prompts for an extra key to select a sparse-tree creating
command.

@item @kbd{C-c / r} or @kbd{C-c / /} (@code{org-occur})
@kindex C-c / r
@kindex C-c / /
@findex org-occur
@vindex org-remove-highlights-with-change
Prompts for a regexp and shows a sparse tree with all matches.  If
the match is in a headline, the headline is made visible.  If the
match is in the body of an entry, headline and body are made
visible.  In order to provide minimal context, also the full
hierarchy of headlines above the match is shown, as well as the
headline following the match.  Each match is also highlighted; the
highlights disappear when the buffer is changed by an editing
command, or by pressing @kbd{C-c C-c}@footnote{This depends on the option @code{org-remove-highlights-with-change}.}.  When called with
a @kbd{C-u} prefix argument, previous highlights are kept, so
several calls to this command can be stacked.

@item @kbd{M-g n} or @kbd{M-g M-n} (@code{next-error})
@kindex M-g n
@kindex M-g M-n
@findex next-error
Jump to the next sparse tree match in this buffer.

@item @kbd{M-g p} or @kbd{M-g M-p} (@code{previous-error})
@kindex M-g p
@kindex M-g M-p
@findex previous-error
Jump to the previous sparse tree match in this buffer.
@end table

@vindex org-agenda-custom-commands
For frequently used sparse trees of specific search strings, you can
use the variable @code{org-agenda-custom-commands} to define fast keyboard
access to specific sparse trees.  These commands will then be
accessible through the agenda dispatcher (see @ref{Agenda Dispatcher}).
For example:

@lisp
(setq org-agenda-custom-commands
      '(("f" occur-tree "FIXME")))
@end lisp

@noindent
defines the key @kbd{f} as a shortcut for creating a sparse tree
matching the string @samp{FIXME}.

The other sparse tree commands select headings based on TODO keywords,
tags, or properties and are discussed later in this manual.

@kindex C-c C-e v
@cindex printing sparse trees
@cindex visible text, printing
To print a sparse tree, you can use the Emacs command
@code{ps-print-buffer-with-faces} which does not print invisible parts of
the document.  Or you can use the command @kbd{C-c C-e v} to
export only the visible part of the document and print the resulting
file.

@node Plain Lists
@section Plain Lists

@cindex plain lists
@cindex lists, plain
@cindex lists, ordered
@cindex ordered lists

Within an entry of the outline tree, hand-formatted lists can provide
additional structure.  They also provide a way to create lists of
checkboxes (see @ref{Checkboxes}).  Org supports editing such lists, and
every exporter (see @ref{Exporting}) can parse and format them.

Org knows ordered lists, unordered lists, and description lists.

@itemize
@item
@emph{Unordered} list items start with @samp{-}, @samp{+}, or @samp{*}@footnote{When using @samp{*} as a bullet, lines must be indented so that they
are not interpreted as headlines.  Also, when you are hiding leading
stars to get a clean outline view, plain list items starting with
a star may be hard to distinguish from true headlines.  In short: even
though @samp{*} is supported, it may be better to not use it for plain list
items.} as bullets.

@item
@vindex org-plain-list-ordered-item-terminator
@vindex org-alphabetical-lists
@emph{Ordered} list items start with a numeral followed by either
a period or a right parenthesis@footnote{You can filter out any of them by configuring
@code{org-plain-list-ordered-item-terminator}.}, such as @samp{1.} or @samp{1)}@footnote{You can also get @samp{a.}, @samp{A.}, @samp{a)} and @samp{A)} by configuring
@code{org-list-allow-alphabetical}.  To minimize confusion with normal
text, those are limited to one character only.  Beyond that limit,
bullets automatically become numbers.}
If you want a list to start with a different value---e.g.,
20---start the text of the item with @samp{[@@20]}@footnote{If there's a checkbox in the item, the cookie must be put
@emph{before} the checkbox.  If you have activated alphabetical lists, you
can also use counters like @samp{[@@b]}.}.  Those
constructs can be used in any item of the list in order to enforce
a particular numbering.

@item
@emph{Description} list items are unordered list items, and contain the
separator @samp{::} to distinguish the description @emph{term} from the
description.
@end itemize

Items belonging to the same list must have the same indentation on the
first line.  In particular, if an ordered list reaches number @samp{10.},
then the 2-digit numbers must be written left-aligned with the other
numbers in the list.  An item ends before the next line that is less
or equally indented than its bullet/number.

A list ends whenever every item has ended, which means before any line
less or equally indented than items at top level.  It also ends before
two blank lines.  In that case, all items are closed.  Here is an
example:

@example
* Lord of the Rings
My favorite scenes are (in this order)
1. The attack of the Rohirrim
2. Eowyn's fight with the witch king
   + this was already my favorite scene in the book
   + I really like Miranda Otto.
3. Peter Jackson being shot by Legolas
   - on DVD only
   He makes a really funny face when it happens.
But in the end, no individual scenes matter but the film as a whole.
Important actors in this film are:
- Elijah Wood :: He plays Frodo
- Sean Astin :: He plays Sam, Frodo's friend. I still remember him
     very well from his role as Mikey Walsh in /The Goonies/.
@end example

Org supports these lists by tuning filling and wrapping commands to
deal with them correctly, and by exporting them properly (see
@ref{Exporting}).  Since indentation is what governs the structure of these
lists, many structural constructs like @samp{#+BEGIN_} blocks can be
indented to signal that they belong to a particular item.

@vindex org-list-demote-modify-bullet
@vindex org-list-indent-offset
If you find that using a different bullet for a sub-list---than that
used for the current list-level---improves readability, customize the
variable @code{org-list-demote-modify-bullet}.  To get a greater difference
of indentation between items and theirs sub-items, customize
@code{org-list-indent-offset}.

@vindex org-list-automatic-rules
The following commands act on items when point is in the first line of
an item---the line with the bullet or number.  Some of them imply the
application of automatic rules to keep list structure intact.  If some
of these actions get in your way, configure @code{org-list-automatic-rules}
to disable them individually.

@table @asis
@item @kbd{@key{TAB}} (@code{org-cycle})
@cindex cycling, in plain lists
@kindex TAB
@findex org-cycle
@vindex org-cycle-include-plain-lists
Items can be folded just like headline levels.  Normally this works
only if point is on a plain list item.  For more details, see the
variable @code{org-cycle-include-plain-lists}.  If this variable is set
to @code{integrate}, plain list items are treated like low-level
headlines.  The level of an item is then given by the indentation of
the bullet/number.  Items are always subordinate to real headlines,
however; the hierarchies remain completely separated.  In a new item
with no text yet, the first @kbd{@key{TAB}} demotes the item to
become a child of the previous one.  Subsequent @kbd{@key{TAB}}s move
the item to meaningful levels in the list and eventually get it back
to its initial position.

@item @kbd{M-@key{RET}} (@code{org-insert-heading})
@kindex M-RET
@findex org-insert-heading
@vindex org-M-RET-may-split-line
Insert new item at current level.  With a prefix argument, force
a new heading (see @ref{Structure Editing}).  If this command is used in
the middle of an item, that item is @emph{split} in two, and the second
part becomes the new item@footnote{If you do not want the item to be split, customize the
variable @code{org-M-RET-may-split-line}.}.  If this command is executed
@emph{before item's body}, the new item is created @emph{before} the current
one.

@item @kbd{M-S-@key{RET}}
@kindex M-S-RET
Insert a new item with a checkbox (see @ref{Checkboxes}).

@item @kbd{S-@key{UP}}
@itemx @kbd{S-@key{DOWN}}
@kindex S-UP
@kindex S-DOWN
@cindex shift-selection-mode
@vindex org-support-shift-select
@vindex org-list-use-circular-motion
Jump to the previous/next item in the current list, but only if
@code{org-support-shift-select} is off@footnote{If you want to cycle around items that way, you may customize
@code{org-list-use-circular-motion}.}.  If not, you can still use
paragraph jumping commands like @kbd{C-@key{UP}} and
@kbd{C-@key{DOWN}} to quite similar effect.

@item @kbd{M-@key{UP}}
@itemx @kbd{M-@key{DOWN}}
@kindex M-UP
@kindex M-DOWN
Move the item including subitems up/down@footnote{See @code{org-list-use-circular-motion} for a cyclic behavior.}, i.e., swap with
previous/next item of same indentation.  If the list is ordered,
renumbering is automatic.

@item @kbd{M-@key{LEFT}}
@itemx @kbd{M-@key{RIGHT}}
@kindex M-LEFT
@kindex M-RIGHT
Decrease/increase the indentation of an item, leaving children
alone.

@item @kbd{M-S-@key{LEFT}}
@itemx @kbd{M-S-@key{RIGHT}}
@kindex M-S-LEFT
@kindex M-S-RIGHT
Decrease/increase the indentation of the item, including subitems.
Initially, the item tree is selected based on current indentation.
When these commands are executed several times in direct succession,
the initially selected region is used, even if the new indentation
would imply a different hierarchy.  To use the new hierarchy, break
the command chain by moving point.

As a special case, using this command on the very first item of
a list moves the whole list.  This behavior can be disabled by
configuring @code{org-list-automatic-rules}.  The global indentation of
a list has no influence on the text @emph{after} the list.

@item @kbd{C-c C-c}
@kindex C-c C-c
If there is a checkbox (see @ref{Checkboxes}) in the item line, toggle
the state of the checkbox.  In any case, verify bullets and
indentation consistency in the whole list.

@item @kbd{C-c -}
@kindex C-c -
@vindex org-plain-list-ordered-item-terminator
Cycle the entire list level through the different itemize/enumerate
bullets (@samp{-}, @samp{+}, @samp{*}, @samp{1.}, @samp{1)}) or a subset of them, depending
on @code{org-plain-list-ordered-item-terminator}, the type of list, and
its indentation.  With a numeric prefix argument N, select the Nth
bullet from this list.  If there is an active region when calling
this, selected text is changed into an item.  With a prefix
argument, all lines are converted to list items.  If the first line
already was a list item, any item marker is removed from the list.
Finally, even without an active region, a normal line is converted
into a list item.

@item @kbd{C-c *}
@kindex C-c *
Turn a plain list item into a headline---so that it becomes
a subheading at its location.  See @ref{Structure Editing}, for
a detailed explanation.

@item @kbd{C-c C-*}
@kindex C-c C-*
Turn the whole plain list into a subtree of the current heading.
Checkboxes (see @ref{Checkboxes}) become @samp{TODO}, respectively @samp{DONE},
keywords when unchecked, respectively checked.

@item @kbd{S-@key{LEFT}}
@itemx @kbd{S-@key{RIGHT}}
@vindex org-support-shift-select
@kindex S-LEFT
@kindex S-RIGHT
This command also cycles bullet styles when point is in on the
bullet or anywhere in an item line, details depending on
@code{org-support-shift-select}.

@item @kbd{C-c ^}
@kindex C-c ^
@cindex sorting, of plain list
Sort the plain list.  Prompt for the sorting method: numerically,
alphabetically, by time, or by custom function.
@end table

@node Drawers
@section Drawers

@cindex drawers
@cindex visibility cycling, drawers

Sometimes you want to keep information associated with an entry, but
you normally do not want to see it.  For this, Org mode has @emph{drawers}.
They can contain anything but a headline and another drawer.  Drawers
look like this:

@example
** This is a headline
Still outside the drawer
:DRAWERNAME:
This is inside the drawer.
:END:
After the drawer.
@end example

@kindex C-c C-x d
@findex org-insert-drawer
You can interactively insert a drawer at point by calling
@code{org-insert-drawer}, which is bound to @kbd{C-c C-x d}.  With an
active region, this command puts the region inside the drawer.  With
a prefix argument, this command calls @code{org-insert-property-drawer},
which creates a @samp{PROPERTIES} drawer right below the current headline.
Org mode uses this special drawer for storing properties (see
@ref{Properties and Columns}).  You cannot use it for anything else.

Completion over drawer keywords is also possible using
@kbd{M-@key{TAB}}@footnote{Many desktops intercept @kbd{M-@key{TAB}} to switch windows.
Use @kbd{C-M-i} or @kbd{@key{ESC} @key{TAB}} instead.}.

Visibility cycling (see @ref{Visibility Cycling}) on the headline hides and
shows the entry, but keep the drawer collapsed to a single line.  In
order to look inside the drawer, you need to move point to the drawer
line and press @kbd{@key{TAB}} there.

You can also arrange for state change notes (see @ref{Tracking TODO state changes}) and clock times (see @ref{Clocking Work Time}) to be stored in
a @samp{LOGBOOK} drawer.  If you want to store a quick note there, in
a similar way to state changes, use

@table @asis
@item @kbd{C-c C-z}
@kindex C-c C-z
Add a time-stamped note to the @samp{LOGBOOK} drawer.
@end table

@node Blocks
@section Blocks

@vindex org-hide-block-startup
@cindex blocks, folding

Org mode uses @samp{#+BEGIN} @dots{} @samp{#+END} blocks for various purposes from
including source code examples (see @ref{Literal Examples}) to capturing
time logging information (see @ref{Clocking Work Time}).  These blocks can
be folded and unfolded by pressing @kbd{@key{TAB}} in the @samp{#+BEGIN}
line.  You can also get all blocks folded at startup by configuring
the variable @code{org-hide-block-startup} or on a per-file basis by using

@cindex STARTUP, keyword
@example
#+STARTUP: hideblocks
#+STARTUP: nohideblocks
@end example

@node Tables
@chapter Tables

@cindex tables
@cindex editing tables

Org comes with a fast and intuitive table editor.  Spreadsheet-like
calculations are supported using the Emacs Calc package (see @ref{Top,GNU Emacs
Calculator Manual,,calc,}).

@menu
* Built-in Table Editor::        Simple tables.
* Column Width and Alignment::   Overrule the automatic settings.
* Column Groups::                Grouping to trigger vertical lines.
* Orgtbl Mode::                  The table editor as minor mode.
* The Spreadsheet::              The table editor has spreadsheet capabilities.
* Org Plot::                     Plotting from Org tables.
@end menu

@node Built-in Table Editor
@section Built-in Table Editor

@cindex table editor, built-in

@cindex header lines, in tables
@cindex horizontal rule, in tables
@cindex row separator, in tables
@cindex table syntax
Org makes it easy to format tables in plain ASCII@.  Any line with @samp{|}
as the first non-whitespace character is considered part of a table.
@samp{|} is also the column separator@footnote{To insert a vertical bar into a table field, use @samp{\vert} or,
inside a word @samp{abc\vert@{@}def}.}.  Moreover, a line starting
with @samp{|-} is a horizontal rule.  It separates rows explicitly.  Rows
before the first horizontal rule are header lines. A table might look
like this:

@example
| Name  | Phone | Age |
|-------+-------+-----|
| Peter |  1234 |  17 |
| Anna  |  4321 |  25 |
@end example

A table is re-aligned automatically each time you press
@kbd{@key{TAB}}, @kbd{@key{RET}} or @kbd{C-c C-c} inside the table.
@kbd{@key{TAB}} also moves to the next field---@kbd{@key{RET}} to the
next row---and creates new table rows at the end of the table or
before horizontal lines.  The indentation of the table is set by the
first line.  Horizontal rules are automatically expanded on every
re-align to span the whole table width.  So, to create the above
table, you would only type

@example
|Name|Phone|Age|
|-
@end example

@noindent
and then press @kbd{@key{TAB}} to align the table and start filling in
fields.  Even faster would be to type @samp{|Name|Phone|Age} followed by
@kbd{C-c @key{RET}}.

When typing text into a field, Org treats @kbd{DEL},
@kbd{Backspace}, and all character keys in a special way, so that
inserting and deleting avoids shifting other fields.  Also, when
typing @emph{immediately} after point was moved into a new field with
@kbd{@key{TAB}}, @kbd{S-@key{TAB}} or @kbd{@key{RET}}, the field is
automatically made blank.  If this behavior is too unpredictable for
you, configure the option @code{org-table-auto-blank-field}.

@anchor{Creation and conversion}
@subheading Creation and conversion

@table @asis
@item @kbd{C-c |} (@code{org-table-create-or-convert-from-region})
@kindex C-c |
@findex org-table-create-or-convert-from-region
Convert the active region to table.  If every line contains at least
one @kbd{@key{TAB}} character, the function assumes that the material
is tab separated.  If every line contains a comma, comma-separated
values (CSV) are assumed.  If not, lines are split at whitespace
into fields.  You can use a prefix argument to force a specific
separator: @kbd{C-u} forces CSV, @kbd{C-u C-u} forces
@kbd{@key{TAB}}, @kbd{C-u C-u C-u} prompts for a regular
expression to match the separator, and a numeric argument
N indicates that at least N consecutive spaces, or alternatively
a @kbd{@key{TAB}} will be the separator.

If there is no active region, this command creates an empty Org
table.  But it is easier just to start typing, like @kbd{| N a m e | P h o n e | A g e @key{RET} | - @key{TAB}}.
@end table

@anchor{Re-aligning and field motion}
@subheading Re-aligning and field motion

@table @asis
@item @kbd{C-c C-c} (@code{org-table-align})
@kindex C-c C-c
@findex org-table-align
Re-align the table without moving point.

@item @kbd{@key{TAB}} (@code{org-table-next-field})
@kindex TAB
@findex org-table-next-field
Re-align the table, move to the next field.  Creates a new row if
necessary.

@item @kbd{C-c @key{SPC}} (@code{org-table-blank-field})
@kindex C-c SPC
@findex org-table-blank-field
Blank the field at point.

@item @kbd{S-@key{TAB}} (@code{org-table-previous-field})
@kindex S-TAB
@findex org-table-previous-field
Re-align, move to previous field.

@item @kbd{@key{RET}} (@code{org-table-next-row})
@kindex RET
@findex org-table-next-row
Re-align the table and move down to next row.  Creates a new row if
necessary.  At the beginning or end of a line, @kbd{@key{RET}} still
inserts a new line, so it can be used to split a table.

@item @kbd{M-a} (@code{org-table-beginning-of-field})
@kindex M-a
@findex org-table-beginning-of-field
Move to beginning of the current table field, or on to the previous
field.

@item @kbd{M-e} (@code{org-table-end-of-field})
@kindex M-e
@findex org-table-end-of-field
Move to end of the current table field, or on to the next field.
@end table

@anchor{Column and row editing}
@subheading Column and row editing

@table @asis
@item @kbd{M-@key{LEFT}} (@code{org-table-move-column-left})
@kindex M-LEFT
@findex org-table-move-column-left
Move the current column left.

@item @kbd{M-@key{RIGHT}} (@code{org-table-move-column-right})
@kindex M-RIGHT
@findex org-table-move-column-right
Move the current column right.

@item @kbd{M-S-@key{LEFT}} (@code{org-table-delete-column})
@kindex M-S-LEFT
@findex org-table-delete-column
Kill the current column.

@item @kbd{M-S-@key{RIGHT}} (@code{org-table-insert-column})
@kindex M-S-RIGHT
@findex org-table-insert-column
Insert a new column to the left of point position.

@item @kbd{M-@key{UP}} (@code{org-table-move-row-up})
@kindex M-UP
@findex org-table-move-row-up
Move the current row up.

@item @kbd{M-@key{DOWN}} (@code{org-table-move-row-down})
@kindex M-DOWN
@findex org-table-move-row-down
Move the current row down.

@item @kbd{M-S-@key{UP}} (@code{org-table-kill-row})
@kindex M-S-UP
@findex org-table-kill-row
Kill the current row or horizontal line.

@item @kbd{S-@key{UP}} (@code{org-table-move-cell-up})
@kindex S-UP
@findex org-table-move-cell-up
Move cell up by swapping with adjacent cell.

@item @kbd{S-@key{DOWN}} (@code{org-table-move-cell-down})
@kindex S-DOWN
@findex org-table-move-cell-down
Move cell down by swapping with adjacent cell.

@item @kbd{S-@key{LEFT}} (@code{org-table-move-cell-left})
@kindex S-LEFT
@findex org-table-move-cell-left
Move cell left by swapping with adjacent cell.

@item @kbd{S-@key{RIGHT}} (@code{org-table-move-cell-right})
@kindex S-RIGHT
@findex org-table-move-cell-right
Move cell right by swapping with adjacent cell.

@item @kbd{M-S-@key{DOWN}} (@code{org-table-insert-row})
@kindex M-S-DOWN
@findex org-table-insert-row
Insert a new row above the current row.  With a prefix argument, the
line is created below the current one.

@item @kbd{C-c -} (@code{org-table-insert-hline})
@kindex C-c -
@findex org-table-insert-hline
Insert a horizontal line below current row.  With a prefix argument,
the line is created above the current line.

@item @kbd{C-c @key{RET}} (@code{org-table-hline-and-move})
@kindex C-c RET
@findex org-table-hline-and-move
Insert a horizontal line below current row, and move point into the
row below that line.

@item @kbd{C-c ^} (@code{org-table-sort-lines})
@kindex C-c ^
@findex org-table-sort-lines
Sort the table lines in the region.  The position of point indicates
the column to be used for sorting, and the range of lines is the
range between the nearest horizontal separator lines, or the entire
table.  If point is before the first column, you are prompted for
the sorting column.  If there is an active region, the mark
specifies the first line and the sorting column, while point should
be in the last line to be included into the sorting.  The command
prompts for the sorting type, alphabetically, numerically, or by
time.  You can sort in normal or reverse order.  You can also supply
your own key extraction and comparison functions.  When called with
a prefix argument, alphabetic sorting is case-sensitive.
@end table

@anchor{Regions}
@subheading Regions

@table @asis
@item @kbd{C-c C-x M-w} (@code{org-table-copy-region})
@kindex C-c C-x M-w
@findex org-table-copy-region
Copy a rectangular region from a table to a special clipboard.
Point and mark determine edge fields of the rectangle.  If there is
no active region, copy just the current field.  The process ignores
horizontal separator lines.

@item @kbd{C-c C-x C-w} (@code{org-table-cut-region})
@kindex C-c C-x C-w
@findex org-table-cut-region
Copy a rectangular region from a table to a special clipboard, and
blank all fields in the rectangle.  So this is the ``cut'' operation.

@item @kbd{C-c C-x C-y} (@code{org-table-paste-rectangle})
@kindex C-c C-x C-y
@findex org-table-paste-rectangle
Paste a rectangular region into a table.  The upper left corner ends
up in the current field.  All involved fields are overwritten.  If
the rectangle does not fit into the present table, the table is
enlarged as needed.  The process ignores horizontal separator lines.

@item @kbd{M-@key{RET}} (@code{org-table-wrap-region})
@kindex M-RET
@findex org-table-wrap-region
Split the current field at point position and move the rest to the
line below.  If there is an active region, and both point and mark
are in the same column, the text in the column is wrapped to minimum
width for the given number of lines.  A numeric prefix argument may
be used to change the number of desired lines.  If there is no
region, but you specify a prefix argument, the current field is made
blank, and the content is appended to the field above.
@end table

@anchor{Calculations}
@subheading Calculations

@cindex formula, in tables
@cindex calculations, in tables

@table @asis
@item @kbd{C-c +} (@code{org-table-sum})
@kindex C-c +
@findex org-table-sum
Sum the numbers in the current column, or in the rectangle defined
by the active region.  The result is shown in the echo area and can
be inserted with @kbd{C-y}.

@item @kbd{S-@key{RET}} (@code{org-table-copy-down})
@kindex S-RET
@findex org-table-copy-down
@vindex org-table-copy-increment
When current field is empty, copy from first non-empty field above.
When not empty, copy current field down to next row and move point
along with it.

Depending on the variable @code{org-table-copy-increment}, integer and
time stamp field values, and fields prefixed or suffixed with
a whole number, can be incremented during copy.  Also, a @code{0} prefix
argument temporarily disables the increment.

This key is also used by shift-selection and related modes (see
@ref{Conflicts}).
@end table

@anchor{Miscellaneous (1)}
@subheading Miscellaneous

@table @asis
@item @kbd{C-c `} (@code{org-table-edit-field})
@kindex C-c `
@findex org-table-edit-field
Edit the current field in a separate window.  This is useful for
fields that are not fully visible (see @ref{Column Width and Alignment}).
When called with a @kbd{C-u} prefix, just make the full field
visible, so that it can be edited in place.  When called with two
@kbd{C-u} prefixes, make the editor window follow point through
the table and always show the current field.  The follow mode exits
automatically when point leaves the table, or when you repeat this
command with @kbd{C-u C-u C-c `}.

@item @kbd{M-x org-table-import}
@findex org-table-import
Import a file as a table.  The table should be TAB or whitespace
separated.  Use, for example, to import a spreadsheet table or data
from a database, because these programs generally can write
TAB-separated text files.  This command works by inserting the file
into the buffer and then converting the region to a table.  Any
prefix argument is passed on to the converter, which uses it to
determine the separator.

@item @kbd{C-c |} (@code{org-table-create-or-convert-from-region})
@kindex C-c |
@findex org-table-create-or-convert-from-region
Tables can also be imported by pasting tabular text into the Org
buffer, selecting the pasted text with @kbd{C-x C-x} and then
using the @kbd{C-c |} command (see @ref{Creation and conversion}).

@item @kbd{M-x org-table-export}
@findex org-table-export
@vindex org-table-export-default-format
Export the table, by default as a TAB-separated file.  Use for data
exchange with, for example, spreadsheet or database programs.  The
format used to export the file can be configured in the variable
@code{org-table-export-default-format}.  You may also use properties
@samp{TABLE_EXPORT_FILE} and @samp{TABLE_EXPORT_FORMAT} to specify the file
name and the format for table export in a subtree.  Org supports
quite general formats for exported tables.  The exporter format is
the same as the format used by Orgtbl radio tables, see @ref{Translator functions}, for a detailed description.
@end table

@node Column Width and Alignment
@section Column Width and Alignment

@cindex narrow columns in tables
@cindex alignment in tables

The width of columns is automatically determined by the table editor.
The alignment of a column is determined automatically from the
fraction of number-like versus non-number fields in the column.

@vindex org-table-automatic-realign
Editing a field may modify alignment of the table.  Moving
a contiguous row or column---i.e., using @kbd{@key{TAB}} or
@kbd{@key{RET}}---automatically re-aligns it.  If you want to disable
this behavior, set @code{org-table-automatic-realign} to @code{nil}.  In any
case, you can always align manually a table:

@table @asis
@item @kbd{C-c C-c} (@code{org-table-align})
@kindex C-c C-c
@findex org-table-align
Align the current table.
@end table

@vindex org-startup-align-all-tables
Setting the option @code{org-startup-align-all-tables} re-aligns all tables
in a file upon visiting it.  You can also set this option on
a per-file basis with:

@example
#+STARTUP: align
#+STARTUP: noalign
@end example

Sometimes a single field or a few fields need to carry more text,
leading to inconveniently wide columns.  Maybe you want to hide away
several columns or display them with a fixed width, regardless of
content, as shown in the following example.

@example
|---+---------------------+--------|           |---+-------…|…|
|   | <6>                 |        |           |   | <6>   …|…|
| 1 | one                 | some   |   ----\   | 1 | one   …|…|
| 2 | two                 | boring |   ----/   | 2 | two   …|…|
| 3 | This is a long text | column |           | 3 | This i…|…|
|---+---------------------+--------|           |---+-------…|…|
@end example

To set the width of a column, one field anywhere in the column may
contain just the string @samp{<N>} where @var{N} specifies the width
as a number of characters.  You control displayed width of columns
with the following tools:

@table @asis
@item @kbd{C-c @key{TAB}} (@code{org-table-toggle-column-width})
@kindex C-c TAB
@findex org-table-toggle-column-width
Shrink or expand current column.

If a width cookie specifies a width W for the column, shrinking it
displays the first W visible characters only.  Otherwise, the column
is shrunk to a single character.

When called before the first column or after the last one, ask for
a list of column ranges to operate on.

@item @kbd{C-u C-c @key{TAB}} (@code{org-table-shrink})
@kindex C-u C-c TAB
@findex org-table-shrink
Shrink all columns with a column width.  Expand the others.

@item @kbd{C-u C-u C-c @key{TAB}} (@code{org-table-expand})
@kindex C-u C-u C-c TAB
@findex org-table-expand
Expand all columns.
@end table

To see the full text of a shrunk field, hold the mouse over it:
a tool-tip window then shows the full contents of the field.
Alternatively, @kbd{C-h .} (@code{display-local-help}) reveals them,
too.  For convenience, any change near the shrunk part of a column
expands it.

@vindex org-startup-shrink-all-tables
Setting the option @code{org-startup-shrink-all-tables} shrinks all columns
containing a width cookie in a file the moment it is visited.  You can
also set this option on a per-file basis with:

@example
#+STARTUP: shrink
@end example


If you would like to overrule the automatic alignment of number-rich
columns to the right and of string-rich columns to the left, you can
use @samp{<r>}, @samp{<c>} or @samp{<l>} in a similar fashion.  You may also combine
alignment and field width like this: @samp{<r10>}.

Lines which only contain these formatting cookies are removed
automatically upon exporting the document.

@node Column Groups
@section Column Groups

@cindex grouping columns in tables

When Org exports tables, it does so by default without vertical lines
because that is visually more satisfying in general.  Occasionally
however, vertical lines can be useful to structure a table into groups
of columns, much like horizontal lines can do for groups of rows.  In
order to specify column groups, you can use a special row where the
first field contains only @samp{/}.  The further fields can either contain
@samp{<} to indicate that this column should start a group, @samp{>} to indicate
the end of a column, or @samp{<>} (no space between @samp{<} and @samp{>}) to make
a column a group of its own.  Upon export, boundaries between column
groups are marked with vertical lines.  Here is an example:

@example
| N | N^2 | N^3 | N^4 | sqrt(n) | sqrt[4](N) |
|---+-----+-----+-----+---------+------------|
| / |  <  |     |  >  |       < |          > |
| 1 |  1  |  1  |  1  |       1 |          1 |
| 2 |  4  |  8  | 16  |  1.4142 |     1.1892 |
| 3 |  9  | 27  | 81  |  1.7321 |     1.3161 |
|---+-----+-----+-----+---------+------------|
#+TBLFM: $2=$1^2::$3=$1^3::$4=$1^4::$5=sqrt($1)::$6=sqrt(sqrt(($1)))
@end example

It is also sufficient to just insert the column group starters after
every vertical line you would like to have:

@example
| N | N^2 | N^3 | N^4 | sqrt(n) | sqrt[4](N) |
|---+-----+-----+-----+---------+------------|
| / | <   |     |     | <       |            |
@end example

@node Orgtbl Mode
@section The Orgtbl Minor Mode

@cindex Orgtbl mode
@cindex minor mode for tables

@findex orgtbl-mode
If you like the intuitive way the Org table editor works, you might
also want to use it in other modes like Text mode or Mail mode.  The
minor mode Orgtbl mode makes this possible.  You can always toggle the
mode with @kbd{M-x orgtbl-mode}.  To turn it on by default, for
example in Message mode, use

@lisp
(add-hook 'message-mode-hook 'turn-on-orgtbl)
@end lisp

Furthermore, with some special setup, it is possible to maintain
tables in arbitrary syntax with Orgtbl mode.  For example, it is
possible to construct @LaTeX{} tables with the underlying ease and power
of Orgtbl mode, including spreadsheet capabilities.  For details, see
@ref{Tables in Arbitrary Syntax}.

@node The Spreadsheet
@section The Spreadsheet

@cindex calculations, in tables
@cindex spreadsheet capabilities
@cindex Calc package

The table editor makes use of the Emacs Calc package to implement
spreadsheet-like capabilities.  It can also evaluate Emacs Lisp forms
to derive fields from other fields.  While fully featured, Org's
implementation is not identical to other spreadsheets.  For example,
Org knows the concept of a @emph{column formula} that will be applied to
all non-header fields in a column without having to copy the formula
to each relevant field.  There is also a formula debugger, and a
formula editor with features for highlighting fields in the table
corresponding to the references at point in the formula, moving these
references by arrow keys.

@menu
* References::                   How to refer to another field or range.
* Formula syntax for Calc::      Using Calc to compute stuff.
* Formula syntax for Lisp::      Writing formulas in Emacs Lisp.
* Durations and time values::    How to compute durations and time values.
* Field and range formulas::     Formula for specific (ranges of) fields.
* Column formulas::              Formulas valid for an entire column.
* Lookup functions::             Lookup functions for searching tables.
* Editing and debugging formulas:: Fixing formulas.
* Updating the table::           Recomputing all dependent fields.
* Advanced features::            Field and column names, automatic recalculation...
@end menu

@node References
@subsection References

@cindex references

To compute fields in the table from other fields, formulas must
reference other fields or ranges.  In Org, fields can be referenced by
name, by absolute coordinates, and by relative coordinates.  To find
out what the coordinates of a field are, press @kbd{C-c ?} in
that field, or press @kbd{C-c @}} to toggle the display of a grid.

@anchor{Field references}
@subsubheading Field references

@cindex field references
@cindex references, to fields
Formulas can reference the value of another field in two ways.  Like
in any other spreadsheet, you may reference fields with
a letter/number combination like @samp{B3}, meaning the second field in the
third row.  However, Org prefers to use another, more general
representation that looks like this:@footnote{Org understands references typed by the user as @samp{B4}, but it
does not use this syntax when offering a formula for editing.  You can
customize this behavior using the variable
@code{org-table-use-standard-references}.}

@example
@@ROW$COLUMN
@end example


Column specifications can be absolute like @samp{$1}, @samp{$2}, @dots{}, @samp{$N}, or
relative to the current column, i.e., the column of the field which is
being computed, like @samp{$+1} or @samp{$-2}.  @samp{$<} and @samp{$>} are immutable
references to the first and last column, respectively, and you can use
@samp{$>>>} to indicate the third column from the right.

The row specification only counts data lines and ignores horizontal
separator lines, or ``hlines''.  Like with columns, you can use absolute
row numbers @samp{@@1}, @samp{@@2}, @dots{}, @samp{@@N}, and row numbers relative to the
current row like @samp{@@+3} or @samp{@@-1}.  @samp{@@<} and @samp{@@>} are immutable
references the first and last row in the table, respectively.  You may
also specify the row relative to one of the hlines: @samp{@@I} refers to the
first hline, @samp{@@II} to the second, etc.  @samp{@@-I} refers to the first such
line above the current line, @samp{@@+I} to the first such line below the
current line.  You can also write @samp{@@III+2} which is the second data
line after the third hline in the table.

@samp{@@0} and @samp{$0} refer to the current row and column, respectively, i.e.,
to the row/column for the field being computed.  Also, if you omit
either the column or the row part of the reference, the current
row/column is implied.

Org's references with @emph{unsigned} numbers are fixed references in the
sense that if you use the same reference in the formula for two
different fields, the same field is referenced each time.  Org's
references with @emph{signed} numbers are floating references because the
same reference operator can reference different fields depending on
the field being calculated by the formula.

Here are a few examples:

@multitable @columnfractions 0.2 0.8
@item @samp{@@2$3}
@tab 2nd row, 3rd column (same as @samp{C2})
@item @samp{$5}
@tab column 5 in the current row (same as @samp{E&})
@item @samp{@@2}
@tab current column, row 2
@item @samp{@@-1$-3}
@tab field one row up, three columns to the left
@item @samp{@@-I$2}
@tab field just under hline above current row, column 2
@item @samp{@@>$5}
@tab field in the last row, in column 5
@end multitable

@anchor{Range references}
@subsubheading Range references

@cindex range references
@cindex references, to ranges
You may reference a rectangular range of fields by specifying two
field references connected by two dots @samp{..}.  If both fields are in
the current row, you may simply use @samp{$2..$7}, but if at least one
field is in a different row, you need to use the general @samp{@@ROW$COLUMN}
format at least for the first field, i.e., the reference must start
with @samp{@@} in order to be interpreted correctly.  Examples:

@multitable @columnfractions 0.2 0.8
@item @samp{$1..$3}
@tab first three fields in the current row
@item @samp{$P..$Q}
@tab range, using column names (see @ref{Advanced features})
@item @samp{$<<<..$>>}
@tab start in third column, continue to the last but one
@item @samp{@@2$1..@@4$3}
@tab six fields between these two fields (same as @samp{A2..C4})
@item @samp{@@-1$-2..@@-1}
@tab 3 fields in the row above, starting from 2 columns on the left
@item @samp{@@I..II}
@tab between first and second hline, short for @samp{@@I..@@II}
@end multitable

@noindent
Range references return a vector of values that can be fed into Calc
vector functions.  Empty fields in ranges are normally suppressed, so
that the vector contains only the non-empty fields.  For other options
with the mode switches @samp{E}, @samp{N} and examples, see @ref{Formula syntax for Calc}.

@anchor{Field coordinates in formulas}
@subsubheading Field coordinates in formulas

@cindex field coordinates
@cindex coordinates, of field
@cindex row, of field coordinates
@cindex column, of field coordinates
@vindex org-table-current-column
@vindex org-table-current-dline
One of the very first actions during evaluation of Calc formulas and
Lisp formulas is to substitute @samp{@@#} and @samp{$#} in the formula with the
row or column number of the field where the current result will go to.
The traditional Lisp formula equivalents are @code{org-table-current-dline}
and @code{org-table-current-column}.  Examples:

@table @asis
@item @samp{if(@@# % 2, $#, string(""))}
Insert column number on odd rows, set field to empty on even rows.

@item @samp{$2 = '(identity remote(FOO, @@@@#$1))}
Copy text or values of each row of column 1 of the table named
@var{FOO} into column 2 of the current table.

@item @samp{@@3 = 2 * remote(FOO, @@@@1$$#)}
Insert the doubled value of each column of row 1 of the table
named @var{FOO} into row 3 of the current table.
@end table

@noindent
For the second and third examples, table @var{FOO} must have at
least as many rows or columns as the current table.  Note that this is
inefficient@footnote{The computation time scales as O(N^2) because table
@var{FOO} is parsed for each field to be copied.} for large number of rows.

@anchor{Named references}
@subsubheading Named references

@cindex named references
@cindex references, named
@cindex name, of column or field
@cindex constants, in calculations
@cindex @samp{CONSTANTS}, keyword
@vindex org-table-formula-constants

@samp{$name} is interpreted as the name of a column, parameter or constant.
Constants are defined globally through the variable
@code{org-table-formula-constants}, and locally---for the file---through
a line like this example:

@example
#+CONSTANTS: c=299792458. pi=3.14 eps=2.4e-6
@end example


@vindex constants-unit-system
@pindex constants.el
Also, properties (see @ref{Properties and Columns}) can be used as
constants in table formulas: for a property @samp{Xyz} use the name
@samp{$PROP_Xyz}, and the property will be searched in the current outline
entry and in the hierarchy above it.  If you have the @samp{constants.el}
package, it will also be used to resolve constants, including natural
constants like @samp{$h} for Planck's constant, and units like @samp{$km} for
kilometers@footnote{The file @samp{constants.el} can supply the values of constants in
two different unit systems, @samp{SI} and @samp{cgs}.  Which one is used depends
on the value of the variable @code{constants-unit-system}.  You can use the
@samp{STARTUP} options @samp{constSI} and @samp{constcgs} to set this value for the
current buffer.}.  Column names and parameters can be specified in
special table lines.  These are described below, see @ref{Advanced features}.  All names must start with a letter, and further consist
of letters and numbers.

@anchor{Remote references}
@subsubheading Remote references

@cindex remote references
@cindex references, remote
@cindex references, to a different table
@cindex name, of column or field
@cindex @samp{NAME}, keyword
You may also reference constants, fields and ranges from a different
table, either in the current file or even in a different file.  The
syntax is

@example
remote(NAME,REF)
@end example


@noindent
where @var{NAME} can be the name of a table in the current file
as set by a @samp{#+NAME:} line before the table.  It can also be the ID of
an entry, even in a different file, and the reference then refers to
the first table in that entry.  @var{REF} is an absolute field or
range reference as described above for example @samp{@@3$3} or @samp{$somename},
valid in the referenced table.

@cindex table indirection
When @var{NAME} has the format @samp{@@ROW$COLUMN}, it is substituted
with the name or ID found in this field of the current table.  For
example @samp{remote($1, @@@@>$2)} @result{} @samp{remote(year_2013, @@@@>$1)}.  The format
@samp{B3} is not supported because it can not be distinguished from a plain
table name or ID@.

@node Formula syntax for Calc
@subsection Formula syntax for Calc

@cindex formula syntax, Calc
@cindex syntax, of formulas

A formula can be any algebraic expression understood by the Emacs Calc
package.  Note that Calc has the non-standard convention that @samp{/} has
lower precedence than @samp{*}, so that @samp{a/b*c} is interpreted as
@samp{(a/(b*c))}.  Before evaluation by @code{calc-eval} (see @ref{Calling Calc from Your Programs,Calling Calc from
Your Lisp Programs,,calc,}), variable substitution takes place according to
the rules described above.

@cindex vectors, in table calculations
The range vectors can be directly fed into the Calc vector functions
like @code{vmean} and @code{vsum}.

@cindex format specifier, in spreadsheet
@cindex mode, for Calc
@vindex org-calc-default-modes
A formula can contain an optional mode string after a semicolon.  This
string consists of flags to influence Calc and other modes during
execution.  By default, Org uses the standard Calc modes (precision
12, angular units degrees, fraction and symbolic modes off).  The
display format, however, has been changed to @samp{(float 8)} to keep
tables compact.  The default settings can be configured using the
variable @code{org-calc-default-modes}.

@table @asis
@item @samp{p20}
Set the internal Calc calculation precision to 20 digits.

@item @samp{n3}, @samp{s3}, @samp{e2}, @samp{f4}
Normal, scientific, engineering or fixed format of the result of
Calc passed back to Org.  Calc formatting is unlimited in precision
as long as the Calc calculation precision is greater.

@item @samp{D}, @samp{R}
Degree and radian angle modes of Calc.

@item @samp{F}, @samp{S}
Fraction and symbolic modes of Calc.

@item @samp{T}, @samp{t}, @samp{U}
Duration computations in Calc or Lisp, @ref{Durations and time values}.

@item @samp{E}
If and how to consider empty fields.  Without @samp{E} empty fields in
range references are suppressed so that the Calc vector or Lisp list
contains only the non-empty fields.  With @samp{E} the empty fields are
kept.  For empty fields in ranges or empty field references the
value @samp{nan} (not a number) is used in Calc formulas and the empty
string is used for Lisp formulas.  Add @samp{N} to use 0 instead for both
formula types.  For the value of a field the mode @samp{N} has higher
precedence than @samp{E}.

@item @samp{N}
Interpret all fields as numbers, use 0 for non-numbers.  See the
next section to see how this is essential for computations with Lisp
formulas.  In Calc formulas it is used only occasionally because
there number strings are already interpreted as numbers without @samp{N}.

@item @samp{L}
Literal, for Lisp formulas only.  See the next section.
@end table

Unless you use large integer numbers or high-precision calculation and
display for floating point numbers you may alternatively provide
a @code{printf} format specifier to reformat the Calc result after it has
been passed back to Org instead of letting Calc already do the
formatting@footnote{The printf reformatting is limited in precision because the
value passed to it is converted into an ``integer'' or ``double''.  The
``integer'' is limited in size by truncating the signed value to 32
bits.  The ``double'' is limited in precision to 64 bits overall which
leaves approximately 16 significant decimal digits.}.  A few examples:

@multitable {aaaaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{$1+$2}
@tab Sum of first and second field
@item @samp{$1+$2;%.2f}
@tab Same, format result to two decimals
@item @samp{exp($2)+exp($1)}
@tab Math functions can be used
@item @samp{$0;%.1f}
@tab Reformat current cell to 1 decimal
@item @samp{($3-32)*5/9}
@tab Degrees F @arrow{} C conversion
@item @samp{$c/$1/$cm}
@tab Hz @arrow{} cm conversion, using @samp{constants.el}
@item @samp{tan($1);Dp3s1}
@tab Compute in degrees, precision 3, display SCI 1
@item @samp{sin($1);Dp3%.1e}
@tab Same, but use @code{printf} specifier for display
@item @samp{vmean($2..$7)}
@tab Compute column range mean, using vector function
@item @samp{vmean($2..$7);EN}
@tab Same, but treat empty fields as 0
@item @samp{taylor($3,x=7,2)}
@tab Taylor series of $3, at x=7, second degree
@end multitable

Calc also contains a complete set of logical operations (see @ref{Logical Operations,Logical
Operations,,calc,}).  For example

@table @asis
@item @samp{if($1 < 20, teen, string(""))}
@samp{"teen"} if age @samp{$1} is less than 20, else the Org table result
field is set to empty with the empty string.

@item @samp{if("$1" =​= "nan" || "$2" =​= "nan", string(""), $1 + $2); E f-1}
Sum of the first two columns.  When at least one of the input fields
is empty the Org table result field is set to empty.  @samp{E} is
required to not convert empty fields to 0.  @samp{f-1} is an optional
Calc format string similar to @samp{%.1f} but leaves empty results empty.

@item @samp{if(typeof(vmean($1..$7)) =​= 12, string(""), vmean($1..$7); E}
Mean value of a range unless there is any empty field.  Every field
in the range that is empty is replaced by @samp{nan} which lets @samp{vmean}
result in @samp{nan}.  Then @samp{typeof =} 12= detects the @samp{nan} from @code{vmean}
and the Org table result field is set to empty.  Use this when the
sample set is expected to never have missing values.

@item @samp{if("$1..$7" =​= "[]", string(""), vmean($1..$7))}
Mean value of a range with empty fields skipped.  Every field in the
range that is empty is skipped.  When all fields in the range are
empty the mean value is not defined and the Org table result field
is set to empty.  Use this when the sample set can have a variable
size.

@item @samp{vmean($1..$7); EN}
To complete the example before: Mean value of a range with empty
fields counting as samples with value 0.  Use this only when
incomplete sample sets should be padded with 0 to the full size.
@end table

You can add your own Calc functions defined in Emacs Lisp with
@code{defmath} and use them in formula syntax for Calc.

@node Formula syntax for Lisp
@subsection Emacs Lisp forms as formulas

@cindex Lisp forms, as table formulas

It is also possible to write a formula in Emacs Lisp.  This can be
useful for string manipulation and control structures, if Calc's
functionality is not enough.

If a formula starts with a single-quote followed by an opening
parenthesis, then it is evaluated as a Lisp form.  The evaluation
should return either a string or a number.  Just as with Calc
formulas, you can specify modes and a @code{printf} format after
a semicolon.

With Emacs Lisp forms, you need to be conscious about the way field
references are interpolated into the form.  By default, a reference is
interpolated as a Lisp string (in double-quotes) containing the field.
If you provide the @samp{N} mode switch, all referenced elements are
numbers---non-number fields will be zero---and interpolated as Lisp
numbers, without quotes.  If you provide the @samp{L} flag, all fields are
interpolated literally, without quotes.  For example, if you want a
reference to be interpreted as a string by the Lisp form, enclose the
reference operator itself in double-quotes, like @samp{"$3"}.  Ranges are
inserted as space-separated fields, so you can embed them in list or
vector syntax.

Here are a few examples---note how the @samp{N} mode is used when we do
computations in Lisp:

@table @asis
@item @samp{'(concat (substring $1 1 2) (substring $1 0 1) (substring $1 2))}
Swap the first two characters of the content of column 1.

@item @samp{'(+ $1 $2);N}
Add columns 1 and 2, equivalent to Calc's @samp{$1+$2}.

@item @samp{'(apply '+ '($1..$4));N}
Compute the sum of columns 1 to 4, like Calc's @samp{vsum($1..$4)}.
@end table

@node Durations and time values
@subsection Durations and time values

@cindex duration, computing
@cindex time, computing
@vindex org-table-duration-custom-format

If you want to compute time values use the @samp{T}, @samp{t}, or @samp{U} flag,
either in Calc formulas or Elisp formulas:

@example
|  Task 1 |   Task 2 |    Total |
|---------+----------+----------|
|    2:12 |     1:47 | 03:59:00 |
|    2:12 |     1:47 |    03:59 |
| 3:02:20 | -2:07:00 |     0.92 |
#+TBLFM: @@2$3=$1+$2;T::@@3$3=$1+$2;U::@@4$3=$1+$2;t
@end example

Input duration values must be of the form @samp{HH:MM[:SS]}, where seconds
are optional.  With the @samp{T} flag, computed durations are displayed as
@samp{HH:MM:SS} (see the first formula above).  With the @samp{U} flag, seconds
are omitted so that the result is only @samp{HH:MM} (see second formula
above).  Zero-padding of the hours field depends upon the value of the
variable @code{org-table-duration-hour-zero-padding}.

With the @samp{t} flag, computed durations are displayed according to the
value of the option @code{org-table-duration-custom-format}, which defaults
to @code{hours} and displays the result as a fraction of hours (see the
third formula in the example above).

Negative duration values can be manipulated as well, and integers are
considered as seconds in addition and subtraction.

@node Field and range formulas
@subsection Field and range formulas

@cindex field formula
@cindex range formula
@cindex formula, for individual table field
@cindex formula, for range of fields

To assign a formula to a particular field, type it directly into the
field, preceded by @samp{:=}, for example @samp{vsum(@@II..III)}.  When you press
@kbd{@key{TAB}} or @kbd{@key{RET}} or @kbd{C-c C-c} with point
still in the field, the formula is stored as the formula for this
field, evaluated, and the current field is replaced with the result.

@cindex @samp{TBLFM}, keyword
Formulas are stored in a special @samp{TBLFM} keyword located directly
below the table.  If you type the equation in the fourth field of the
third data line in the table, the formula looks like @samp{@@3$4=$1+$2}.
When inserting/deleting/swapping column and rows with the appropriate
commands, @emph{absolute references} (but not relative ones) in stored
formulas are modified in order to still reference the same field.  To
avoid this from happening, in particular in range references, anchor
ranges at the table borders (using @samp{@@<}, @samp{@@>}, @samp{$<}, @samp{$>}), or at
hlines using the @samp{@@I} notation.  Automatic adaptation of field
references does not happen if you edit the table structure with normal
editing commands---you must fix the formulas yourself.

Instead of typing an equation into the field, you may also use the
following command

@table @asis
@item @kbd{C-u C-c =} (@code{org-table-eval-formula})
@kindex C-u C-c =
@findex org-table-eval-formula
Install a new formula for the current field.  The command prompts
for a formula with default taken from the @samp{TBLFM} keyword,
applies it to the current field, and stores it.
@end table

The left-hand side of a formula can also be a special expression in
order to assign the formula to a number of different fields.  There is
no keyboard shortcut to enter such range formulas.  To add them, use
the formula editor (see @ref{Editing and debugging formulas}) or edit
the @samp{TBLFM} keyword directly.

@table @asis
@item @samp{$2=}
Column formula, valid for the entire column.  This is so common that
Org treats these formulas in a special way, see @ref{Column formulas}.

@item @samp{@@3=}
Row formula, applies to all fields in the specified row.  @samp{@@>=}
means the last row.

@item @samp{@@1$2..@@4$3=}
Range formula, applies to all fields in the given rectangular range.
This can also be used to assign a formula to some but not all fields
in a row.

@item @samp{$NAME=}
Named field, see @ref{Advanced features}.
@end table

@node Column formulas
@subsection Column formulas

@cindex column formula
@cindex formula, for table column

When you assign a formula to a simple column reference like @samp{$3=}, the
same formula is used in all fields of that column, with the following
very convenient exceptions: (i) If the table contains horizontal
separator hlines with rows above and below, everything before the
first such hline is considered part of the table @emph{header} and is not
modified by column formulas.  Therefore a header is mandatory when you
use column formulas and want to add hlines to group rows, like for
example to separate a total row at the bottom from the summand rows
above.  (ii) Fields that already get a value from a field/range
formula are left alone by column formulas.  These conditions make
column formulas very easy to use.

To assign a formula to a column, type it directly into any field in
the column, preceded by an equal sign, like @samp{=$1+$2}.  When you press
@kbd{@key{TAB}} or @kbd{@key{RET}} or @kbd{C-c C-c} with point
still in the field, the formula is stored as the formula for the
current column, evaluated and the current field replaced with the
result.  If the field contains only @samp{=}, the previously stored formula
for this column is used.  For each column, Org only remembers the most
recently used formula.  In the @samp{TBLFM} keyword, column formulas look
like @samp{$4=$1+$2}.  The left-hand side of a column formula can not be
the name of column, it must be the numeric column reference or @samp{$>}.

Instead of typing an equation into the field, you may also use the
following command:

@table @asis
@item @kbd{C-c =} (@code{org-table-eval-formula})
@kindex C-c =
@findex org-table-eval-formula
Install a new formula for the current column and replace current
field with the result of the formula.  The command prompts for
a formula, with default taken from the @samp{TBLFM} keyword, applies it
to the current field and stores it.  With a numeric prefix argument,
e.g., @kbd{C-5 C-c =}, the command applies it to that many
consecutive fields in the current column.
@end table

@node Lookup functions
@subsection Lookup functions

@cindex lookup functions in tables
@cindex table lookup functions

Org has three predefined Emacs Lisp functions for lookups in tables.

@table @asis
@item @samp{(org-lookup-first VAL S-LIST R-LIST &optional PREDICATE)}
@findex org-lookup-first
Searches for the first element @var{S} in list
@var{S-LIST} for which
@lisp
(PREDICATE VAL S)
@end lisp
is non-@code{nil}; returns the value from the corresponding position in
list @var{R-LIST}.  The default @var{PREDICATE} is
@code{equal}.  Note that the parameters @var{VAL} and @var{S}
are passed to @var{PREDICATE} in the same order as the
corresponding parameters are in the call to @code{org-lookup-first},
where @var{VAL} precedes @var{S-LIST}.  If
@var{R-LIST} is @code{nil}, the matching element @var{S} of
@var{S-LIST} is returned.

@item @samp{(org-lookup-last VAL S-LIST R-LIST &optional PREDICATE)}
@findex org-lookup-last
Similar to @code{org-lookup-first} above, but searches for the @emph{last}
element for which @var{PREDICATE} is non-@code{nil}.

@item @samp{(org-lookup-all VAL S-LIST R-LIST &optional PREDICATE)}
@findex org-lookup-all
Similar to @code{org-lookup-first}, but searches for @emph{all} elements for
which @var{PREDICATE} is non-@code{nil}, and returns @emph{all}
corresponding values.  This function can not be used by itself in
a formula, because it returns a list of values.  However, powerful
lookups can be built when this function is combined with other Emacs
Lisp functions.
@end table

If the ranges used in these functions contain empty fields, the @samp{E}
mode for the formula should usually be specified: otherwise empty
fields are not included in @var{S-LIST} and/or @var{R-LIST}
which can, for example, result in an incorrect mapping from an element
of @var{S-LIST} to the corresponding element of
@var{R-LIST}.

These three functions can be used to implement associative arrays,
count matching cells, rank results, group data, etc.  For practical
examples see @uref{https://orgmode.org/worg/org-tutorials/org-lookups.html, this tutorial on Worg}.

@node Editing and debugging formulas
@subsection Editing and debugging formulas

@cindex formula editing
@cindex editing, of table formulas

@vindex org-table-use-standard-references
You can edit individual formulas in the minibuffer or directly in the
field.  Org can also prepare a special buffer with all active formulas
of a table.  When offering a formula for editing, Org converts
references to the standard format (like @samp{B3} or @samp{D&}) if possible.  If
you prefer to only work with the internal format (like @samp{@@3$2} or
@samp{$4}), configure the variable @code{org-table-use-standard-references}.

@table @asis
@item @kbd{C-c =} or @kbd{C-u C-c =} (@code{org-table-eval-formula})
@kindex C-c =
@kindex C-u C-c =
@findex org-table-eval-formula
Edit the formula associated with the current column/field in the
minibuffer.  See @ref{Column formulas}, and @ref{Field and range formulas}.

@item @kbd{C-u C-u C-c =} (@code{org-table-eval-formula})
@kindex C-u C-u C-c =
@findex org-table-eval-formula
Re-insert the active formula (either a field formula, or a column
formula) into the current field, so that you can edit it directly in
the field.  The advantage over editing in the minibuffer is that you
can use the command @kbd{C-c ?}.

@item @kbd{C-c ?} (@code{org-table-field-info})
@kindex C-c ?
@findex org-table-field-info
While editing a formula in a table field, highlight the field(s)
referenced by the reference at point position in the formula.

@item @kbd{C-c @}} (@code{org-table-toggle-coordinate-overlays})
@kindex C-c @}
@findex org-table-toggle-coordinate-overlays
Toggle the display of row and column numbers for a table, using
overlays.  These are updated each time the table is aligned; you can
force it with @kbd{C-c C-c}.

@item @kbd{C-c @{} (@code{org-table-toggle-formula-debugger})
@kindex C-c @{
@findex org-table-toggle-formula-debugger
Toggle the formula debugger on and off.  See below.

@item @kbd{C-c '} (@code{org-table-edit-formulas})
@kindex C-c '
@findex org-table-edit-formulas
Edit all formulas for the current table in a special buffer, where
the formulas are displayed one per line.  If the current field has
an active formula, point in the formula editor marks it.  While
inside the special buffer, Org automatically highlights any field or
range reference at point position.  You may edit, remove and add
formulas, and use the following commands:

@table @asis
@item @kbd{C-c C-c} or @kbd{C-x C-s} (@code{org-table-fedit-finish})
@kindex C-x C-s
@kindex C-c C-c
@findex org-table-fedit-finish
Exit the formula editor and store the modified formulas.  With
@kbd{C-u} prefix, also apply the new formulas to the
entire table.

@item @kbd{C-c C-q} (@code{org-table-fedit-abort})
@kindex C-c C-q
@findex org-table-fedit-abort
Exit the formula editor without installing changes.

@item @kbd{C-c C-r} (@code{org-table-fedit-toggle-ref-type})
@kindex C-c C-r
@findex org-table-fedit-toggle-ref-type
Toggle all references in the formula editor between standard (like
@samp{B3}) and internal (like @samp{@@3$2}).

@item @kbd{@key{TAB}} (@code{org-table-fedit-lisp-indent})
@kindex TAB
@findex org-table-fedit-lisp-indent
Pretty-print or indent Lisp formula at point.  When in a line
containing a Lisp formula, format the formula according to Emacs
Lisp rules.  Another @kbd{@key{TAB}} collapses the formula back
again.  In the open formula, @kbd{@key{TAB}} re-indents just like
in Emacs Lisp mode.

@item @kbd{M-@key{TAB}} (@code{lisp-complete-symbol})
@kindex M-TAB
@findex lisp-complete-symbol
Complete Lisp symbols, just like in Emacs Lisp mode.

@item @kbd{S-@key{UP}}, @kbd{S-@key{DOWN}}, @kbd{S-@key{LEFT}}, @kbd{S-@key{RIGHT}}
@kindex S-UP
@kindex S-DOWN
@kindex S-LEFT
@kindex S-RIGHT
@findex org-table-fedit-ref-up
@findex org-table-fedit-ref-down
@findex org-table-fedit-ref-left
@findex org-table-fedit-ref-right
Shift the reference at point.  For example, if the reference is
@samp{B3} and you press @kbd{S-@key{RIGHT}}, it becomes @samp{C3}.  This also
works for relative references and for hline references.

@item @kbd{M-S-@key{UP}} (@code{org-table-fedit-line-up})
@kindex M-S-UP
@findex org-table-fedit-line-up
Move the test line for column formulas up in the Org buffer.

@item @kbd{M-S-@key{DOWN}} (@code{org-table-fedit-line-down})
@kindex M-S-DOWN
@findex org-table-fedit-line-down
Move the test line for column formulas down in the Org buffer.

@item @kbd{M-@key{UP}} (@code{org-table-fedit-scroll-up})
@kindex M-UP
@findex org-table-fedit-scroll-up
Scroll up the window displaying the table.

@item @kbd{M-@key{DOWN}} (@code{org-table-fedit-scroll-down})
@kindex M-DOWN
@findex org-table-fedit-scroll-down
Scroll down the window displaying the table.

@item @kbd{C-c @}}
@kindex C-c @}
@findex org-table-toggle-coordinate-overlays
Turn the coordinate grid in the table on and off.
@end table
@end table

Making a table field blank does not remove the formula associated with
the field, because that is stored in a different line---the @samp{TBLFM}
keyword line.  During the next recalculation, the field will be filled
again.  To remove a formula from a field, you have to give an empty
reply when prompted for the formula, or to edit the @samp{TBLFM} keyword.

@kindex C-c C-c
You may edit the @samp{TBLFM} keyword directly and re-apply the changed
equations with @kbd{C-c C-c} in that line or with the normal
recalculation commands in the table.

@anchor{Using multiple @samp{TBLFM} lines}
@subsubheading Using multiple @samp{TBLFM} lines

@cindex multiple formula lines
@cindex @samp{TBLFM} keywords, multiple
@cindex @samp{TBLFM}, switching

@kindex C-c C-c
You may apply the formula temporarily.  This is useful when you want
to switch the formula applied to the table.  Place multiple @samp{TBLFM}
keywords right after the table, and then press @kbd{C-c C-c} on
the formula to apply.  Here is an example:

@example
| x | y |
|---+---|
| 1 |   |
| 2 |   |
#+TBLFM: $2=$1*1
#+TBLFM: $2=$1*2
@end example

@noindent
Pressing @kbd{C-c C-c} in the line of @samp{#+TBLFM: $2=$1*2} yields:

@example
| x | y |
|---+---|
| 1 | 2 |
| 2 | 4 |
#+TBLFM: $2=$1*1
#+TBLFM: $2=$1*2
@end example

@noindent
If you recalculate this table, with @kbd{C-u C-c *}, for example,
you get the following result from applying only the first @samp{TBLFM}
keyword.

@example
| x | y |
|---+---|
| 1 | 1 |
| 2 | 2 |
#+TBLFM: $2=$1*1
#+TBLFM: $2=$1*2
@end example

@anchor{Debugging formulas}
@subsubheading Debugging formulas

@cindex formula debugging
@cindex debugging, of table formulas

When the evaluation of a formula leads to an error, the field content
becomes the string @samp{#ERROR}.  If you would like to see what is going
on during variable substitution and calculation in order to find
a bug, turn on formula debugging in the Tbl menu and repeat the
calculation, for example by pressing @kbd{C-u C-u C-c = @key{RET}} in
a field.  Detailed information are displayed.

@node Updating the table
@subsection Updating the table

@cindex recomputing table fields
@cindex updating, table

Recalculation of a table is normally not automatic, but needs to be
triggered by a command.  To make recalculation at least
semi-automatic, see @ref{Advanced features}.

In order to recalculate a line of a table or the entire table, use the
following commands:

@table @asis
@item @kbd{C-c *} (@code{org-table-recalculate})
@kindex C-c *
@findex org-table-recalculate
Recalculate the current row by first applying the stored column
formulas from left to right, and all field/range formulas in the
current row.

@item @kbd{C-u C-c *} or @kbd{C-u C-c C-c}
@kindex C-u C-c *
@kindex C-u C-c C-c
Recompute the entire table, line by line.  Any lines before the
first hline are left alone, assuming that these are part of the
table header.

@item @kbd{C-u C-u C-c *} or @kbd{C-u C-u C-c C-c} (@code{org-table-iterate})
@kindex C-u C-u C-c *
@kindex C-u C-u C-c C-c
@findex org-table-iterate
Iterate the table by recomputing it until no further changes occur.
This may be necessary if some computed fields use the value of other
fields that are computed @emph{later} in the calculation sequence.

@item @kbd{M-x org-table-recalculate-buffer-tables}
@findex org-table-recalculate-buffer-tables
Recompute all tables in the current buffer.

@item @kbd{M-x org-table-iterate-buffer-tables}
@findex org-table-iterate-buffer-tables
Iterate all tables in the current buffer, in order to converge
table-to-table dependencies.
@end table

@node Advanced features
@subsection Advanced features

If you want the recalculation of fields to happen automatically, or if
you want to be able to assign @emph{names}@footnote{Such names must start with an alphabetic character and use
only alphanumeric/underscore characters.} to fields and columns,
you need to reserve the first column of the table for special marking
characters.

@table @asis
@item @kbd{C-#} (@code{org-table-rotate-recalc-marks})
@kindex C-#
@findex org-table-rotate-recalc-marks
Rotate the calculation mark in first column through the states @samp{#},
@samp{*}, @samp{!}, @samp{$}.  When there is an active region, change all marks in
the region.
@end table

Here is an example of a table that collects exam results of students
and makes use of these features:

@example
|---+---------+--------+--------+--------+-------+------|
|   | Student | Prob 1 | Prob 2 | Prob 3 | Total | Note |
|---+---------+--------+--------+--------+-------+------|
| ! |         |     P1 |     P2 |     P3 |   Tot |      |
| # | Maximum |     10 |     15 |     25 |    50 | 10.0 |
| ^ |         |     m1 |     m2 |     m3 |    mt |      |
|---+---------+--------+--------+--------+-------+------|
| # | Peter   |     10 |      8 |     23 |    41 |  8.2 |
| # | Sam     |      2 |      4 |      3 |     9 |  1.8 |
|---+---------+--------+--------+--------+-------+------|
|   | Average |        |        |        |  25.0 |      |
| ^ |         |        |        |        |    at |      |
| $ | max=50  |        |        |        |       |      |
|---+---------+--------+--------+--------+-------+------|
#+TBLFM: $6=vsum($P1..$P3)::$7=10*$Tot/$max;%.1f::$at=vmean(@@-II..@@-I);%.1f
@end example

@quotation Important
Please note that for these special tables, recalculating the table
with @kbd{C-u C-c *} only affects rows that are marked @samp{#} or
@samp{*}, and fields that have a formula assigned to the field itself.  The
column formulas are not applied in rows with empty first field.

@end quotation

@cindex marking characters, tables
The marking characters have the following meaning:

@table @asis
@item @samp{!}
The fields in this line define names for the columns, so that you
may refer to a column as @samp{$Tot} instead of @samp{$6}.

@item @samp{^}
This row defines names for the fields @emph{above} the row.  With such
a definition, any formula in the table may use @samp{$m1} to refer to the
value @samp{10}.  Also, if you assign a formula to a names field, it is
stored as @samp{$name = ...}.

@item @samp{_}
Similar to @samp{^}, but defines names for the fields in the row @emph{below}.

@item @samp{$}
Fields in this row can define @emph{parameters} for formulas.  For
example, if a field in a @samp{$} row contains @samp{max=50}, then formulas in
this table can refer to the value 50 using @samp{$max}.  Parameters work
exactly like constants, only that they can be defined on a per-table
basis.

@item @samp{#}
Fields in this row are automatically recalculated when pressing
@kbd{@key{TAB}} or @kbd{@key{RET}} or @kbd{S-@key{TAB}} in this row.
Also, this row is selected for a global recalculation with
@kbd{C-u C-c *}.  Unmarked lines are left alone by this
command.

@item @samp{*}
Selects this line for global recalculation with @kbd{C-u C-c *}, but not for automatic recalculation.  Use this when automatic
recalculation slows down editing too much.

@item @samp{/}
Do not export this line.  Useful for lines that contain the
narrowing @samp{<N>} markers or column group markers.
@end table

Finally, just to whet your appetite for what can be done with the
fantastic Calc package, here is a table that computes the Taylor
series of degree n at location x for a couple of functions.

@example
|---+-------------+---+-----+--------------------------------------|
|   | Func        | n | x   | Result                               |
|---+-------------+---+-----+--------------------------------------|
| # | exp(x)      | 1 | x   | 1 + x                                |
| # | exp(x)      | 2 | x   | 1 + x + x^2 / 2                      |
| # | exp(x)      | 3 | x   | 1 + x + x^2 / 2 + x^3 / 6            |
| # | x^2+sqrt(x) | 2 | x=0 | x*(0.5 / 0) + x^2 (2 - 0.25 / 0) / 2 |
| # | x^2+sqrt(x) | 2 | x=1 | 2 + 2.5 x - 2.5 + 0.875 (x - 1)^2    |
| * | tan(x)      | 3 | x   | 0.0175 x + 1.77e-6 x^3               |
|---+-------------+---+-----+--------------------------------------|
#+TBLFM: $5=taylor($2,$4,$3);n3
@end example

@node Org Plot
@section Org Plot

@cindex graph, in tables
@cindex plot tables using Gnuplot

Org Plot can produce graphs of information stored in Org tables,
either graphically or in ASCII art.

@anchor{Graphical plots using Gnuplot}
@subheading Graphical plots using Gnuplot

@cindex @samp{PLOT}, keyword
Org Plot can produce 2D and 3D graphs of information stored in Org
tables using @uref{http://www.gnuplot.info/, Gnuplot} and @uref{http://cars9.uchicago.edu/~ravel/software/gnuplot-mode.html, Gnuplot mode}.  To see this in action, ensure
that you have both Gnuplot and Gnuplot mode installed on your system,
then call @kbd{C-c " g} or @kbd{M-x org-plot/gnuplot} on the
following table.

@example
#+PLOT: title:"Citas" ind:1 deps:(3) type:2d with:histograms set:"yrange [0:]"
| Sede      | Max cites | H-index |
|-----------+-----------+---------|
| Chile     |    257.72 |   21.39 |
| Leeds     |    165.77 |   19.68 |
| Sao Paolo |     71.00 |   11.50 |
| Stockholm |    134.19 |   14.33 |
| Morelia   |    257.56 |   17.67 |
@end example

Notice that Org Plot is smart enough to apply the table's headers as
labels.  Further control over the labels, type, content, and
appearance of plots can be exercised through the @samp{PLOT} keyword
preceding a table.  See below for a complete list of Org Plot options.
For more information and examples see the @uref{https://orgmode.org/worg/org-tutorials/org-plot.html, Org Plot tutorial}.

@anchor{Plot options}
@subsubheading Plot options

@table @asis
@item @samp{set}
Specify any Gnuplot option to be set when graphing.

@item @samp{title}
Specify the title of the plot.

@item @samp{ind}
Specify which column of the table to use as the @samp{x} axis.

@item @samp{deps}
Specify the columns to graph as a Lisp style list, surrounded by
parentheses and separated by spaces for example @samp{dep:(3 4)} to graph
the third and fourth columns.  Defaults to graphing all other
columns aside from the @samp{ind} column.

@item @samp{type}
Specify whether the plot is @samp{2d}, @samp{3d}, or @samp{grid}.

@item @samp{with}
Specify a @samp{with} option to be inserted for every column being
plotted, e.g., @samp{lines}, @samp{points}, @samp{boxes}, @samp{impulses}.  Defaults to
@samp{lines}.

@item @samp{file}
If you want to plot to a file, specify
@samp{"path/to/desired/output-file"}.

@item @samp{labels}
List of labels to be used for the @samp{deps}.  Defaults to the column
headers if they exist.

@item @samp{line}
Specify an entire line to be inserted in the Gnuplot script.

@item @samp{map}
When plotting @samp{3d} or @samp{grid} types, set this to @samp{t} to graph a flat
mapping rather than a @samp{3d} slope.

@item @samp{timefmt}
Specify format of Org mode timestamps as they will be parsed by
Gnuplot.  Defaults to @samp{%Y-%m-%d-%H:%M:%S}.

@item @samp{script}
If you want total control, you can specify a script file---place the
file name between double-quotes---which will be used to plot.
Before plotting, every instance of @samp{$datafile} in the specified
script will be replaced with the path to the generated data file.
Note: even if you set this option, you may still want to specify the
plot type, as that can impact the content of the data file.
@end table

@anchor{ASCII bar plots}
@subheading ASCII bar plots

While point is on a column, typing @kbd{C-c `` a} or @kbd{M-x orgtbl-ascii-plot} create a new column containing an ASCII-art bars
plot.  The plot is implemented through a regular column formula.  When
the source column changes, the bar plot may be updated by refreshing
the table, for example typing @kbd{C-u C-c *}.

@example
| Sede          | Max cites |              |
|---------------+-----------+--------------|
| Chile         |    257.72 | WWWWWWWWWWWW |
| Leeds         |    165.77 | WWWWWWWh     |
| Sao Paolo     |     71.00 | WWW;         |
| Stockholm     |    134.19 | WWWWWW:      |
| Morelia       |    257.56 | WWWWWWWWWWWH |
| Rochefourchat |      0.00 |              |
#+TBLFM: $3='(orgtbl-ascii-draw $2 0.0 257.72 12)
@end example

The formula is an Elisp call.

@defun orgtbl-ascii-draw value min max &optional width
Draw an ASCII bar in a table.

@var{VALUE} is the value to plot.

@var{MIN} is the value displayed as an empty bar.  @var{MAX}
is the value filling all the @var{WIDTH}.  Sources values outside
this range are displayed as @samp{too small} or @samp{too large}.

@var{WIDTH} is the number of characters of the bar plot.  It
defaults to @samp{12}.
@end defun

@node Hyperlinks
@chapter Hyperlinks

@cindex hyperlinks

Like HTML, Org provides support for links inside a file, external
links to other files, Usenet articles, emails, and much more.

@menu
* Link Format::                  How links in Org are formatted.
* Internal Links::               Links to other places in the current file.
* Radio Targets::                Make targets trigger links in plain text.
* External Links::               URL-like links to the world.
* Handling Links::               Creating, inserting and following.
* Using Links Outside Org::      Linking from my C source code?
* Link Abbreviations::           Shortcuts for writing complex links.
* Search Options::               Linking to a specific location.
* Custom Searches::              When the default search is not enough.
@end menu

@node Link Format
@section Link Format

@cindex link format
@cindex format, of links

@cindex angle bracket links
@cindex plain links
Org recognizes plain URIs, possibly wrapped within angle
brackets@footnote{Plain URIs are recognized only for a well-defined set of
schemes.  See @ref{External Links}.  Unlike URI syntax, they cannot contain
parenthesis or white spaces, either.  URIs within angle brackets have
no such limitation.}, and activate them as clickable links.

@cindex bracket links
The general link format, however, looks like this:

@example
[[LINK][DESCRIPTION]]
@end example


@noindent
or alternatively

@example
[[LINK]]
@end example


@cindex escape syntax, for links
@cindex backslashes, in links
Some @samp{\} and @samp{]} characters in the @var{LINK} part need to be
``escaped'', i.e., preceded by another @samp{\} character.  More
specifically, the following character categories, and only them, must
be escaped, in order:

@enumerate
@item
all consecutive @samp{\} characters at the end of the link,
@item
any @samp{]} character at the very end of the link,
@item
all consecutive @samp{\} characters preceding @samp{][} or @samp{]]} patterns,
@item
any @samp{]} character followed by either @samp{[} or @samp{]}.
@end enumerate

@findex org-link-escape
Org takes for granted that such links are correctly escaped.
Functions inserting links (see @ref{Handling Links}) take care of this.
You only need to bother about those rules when inserting directly, or
yanking, a URI within square brackets.  When in doubt, you may use the
function @code{org-link-escape}, which turns a link string into its
properly escaped form.

Once a link in the buffer is complete, with all brackets present, Org
changes the display so that @samp{DESCRIPTION} is displayed instead of
@samp{[[LINK][DESCRIPTION]]} and @samp{LINK} is displayed instead of @samp{[[LINK]]}.
Links are highlighted in the @code{org-link} face, which, by default, is an
underlined face.

You can directly edit the visible part of a link.  This can be either
the @var{LINK} part, if there is no description, or the
@var{DESCRIPTION} part otherwise.  To also edit the invisible
@var{LINK} part, use @kbd{C-c C-l} with point on the link
(see @ref{Handling Links}).

If you place point at the beginning or just behind the end of the
displayed text and press @kbd{@key{BS}}, you remove
the---invisible---bracket at that location@footnote{More accurately, the precise behavior depends on how point
arrived there---see @ref{Invisible Text,Invisible Text,,elisp,}.}.  This makes the link
incomplete and the internals are again displayed as plain text.
Inserting the missing bracket hides the link internals again.  To show
the internal structure of all links, use the menu: Org @arrow{} Hyperlinks @arrow{}
Literal links.

@node Internal Links
@section Internal Links

@cindex internal links
@cindex links, internal
@cindex targets, for links

@cindex @samp{CUSTOM_ID}, property
If the link does not look like a URL, it is considered to be internal
in the current file.  The most important case is a link like
@samp{[[#my-custom-id]]} which links to the entry with the @samp{CUSTOM_ID} property
@samp{my-custom-id}.  You are responsible yourself to make sure these
custom IDs are unique in a file.

Links such as @samp{[[My Target]]} or @samp{[[My Target][Find my target]]} lead to a text search in
the current file.

The link can be followed with @kbd{C-c C-o} when point is on
the link, or with a mouse click (see @ref{Handling Links}).  Links to
custom IDs point to the corresponding headline.  The preferred match
for a text link is a @emph{dedicated target}: the same string in double
angular brackets, like @samp{<<My Target>>}.

@cindex @samp{NAME}, keyword
If no dedicated target exists, the link tries to match the exact name
of an element within the buffer.  Naming is done with the @samp{NAME}
keyword, which has to be put in the line before the element it refers
to, as in the following example

@example
#+NAME: My Target
| a  | table      |
|----+------------|
| of | four cells |
@end example

If none of the above succeeds, Org searches for a headline that is
exactly the link text but may also include a TODO keyword and
tags@footnote{To insert a link targeting a headline, in-buffer completion
can be used.  Just type a star followed by a few optional letters into
the buffer and press @kbd{M-@key{TAB}}.  All headlines in the current
buffer are offered as completions.}.

During export, internal links are used to mark objects and assign them
a number.  Marked objects are then referenced by links pointing to
them.  In particular, links without a description appear as the number
assigned to the marked object@footnote{When targeting a @samp{NAME} keyword, the @samp{CAPTION} keyword is
mandatory in order to get proper numbering (see @ref{Captions}).}.  In the following excerpt from
an Org buffer

@example
1. one item
2. <<target>>another item
Here we refer to item [[target]].
@end example

@noindent
The last sentence will appear as @samp{Here we refer to item 2} when
exported.

In non-Org files, the search looks for the words in the link text.  In
the above example the search would be for @samp{target}.

Following a link pushes a mark onto Org's own mark ring.  You can
return to the previous position with @kbd{C-c &}.  Using this
command several times in direct succession goes back to positions
recorded earlier.

@node Radio Targets
@section Radio Targets

@cindex radio targets
@cindex targets, radio
@cindex links, radio targets

Org can automatically turn any occurrences of certain target names in
normal text into a link.  So without explicitly creating a link, the
text connects to the target radioing its position.  Radio targets are
enclosed by triple angular brackets.  For example, a target @samp{<<<My
Target>>>} causes each occurrence of @samp{my target} in normal text to
become activated as a link.  The Org file is scanned automatically for
radio targets only when the file is first loaded into Emacs.  To
update the target list during editing, press @kbd{C-c C-c} with
point on or at a target.

@node External Links
@section External Links

@cindex links, external
@cindex external links
@cindex attachment links
@cindex BBDB links
@cindex Elisp links
@cindex file links
@cindex Gnus links
@cindex Help links
@cindex IRC links
@cindex Info links
@cindex MH-E links
@cindex Rmail links
@cindex shell links
@cindex URL links
@cindex Usenet links

Org supports links to files, websites, Usenet and email messages, BBDB
database entries and links to both IRC conversations and their logs.
External links are URL-like locators.  They start with a short
identifying string followed by a colon.  There can be no space after
the colon.

Here is the full set of built-in link types:

@table @asis
@item @samp{file}
File links.  File name may be remote, absolute, or relative.

Additionally, you can specify a line number, or a text search.
In Org files, you may link to a headline name, a custom ID, or a
code reference instead.

As a special case, ``file'' prefix may be omitted if the file name
is complete, e.g., it starts with @samp{./}, or @samp{/}.

@item @samp{attachment}
Same as file links but for files and folders attached to the current
node (see @ref{Attachments}).  Attachment links are intended to behave
exactly as file links but for files relative to the attachment
directory.

@item @samp{bbdb}
Link to a BBDB record, with possible regexp completion.

@item @samp{docview}
Link to a document opened with DocView mode.  You may specify a page
number.

@item @samp{doi}
Link to an electronic resource, through its handle.

@item @samp{elisp}
Execute an Elisp command upon activation.

@item @samp{gnus}, @samp{rmail}, @samp{mhe}
Link to messages or folders from a given Emacs' MUA@.

@item @samp{help}
Display documentation of a symbol in @samp{*Help*} buffer.

@item @samp{http}, @samp{https}
Web links.

@item @samp{id}
Link to a specific headline by its ID property, in an Org file.

@item @samp{info}
Link to an Info manual, or to a specific node.

@item @samp{irc}
Link to an IRC channel.

@item @samp{mailto}
Link to message composition.

@item @samp{news}
Usenet links.

@item @samp{shell}
Execute a shell command upon activation.
@end table

The following table illustrates the link types above, along with their
options:

@multitable {aaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@headitem Link Type
@tab Example
@item http
@tab @samp{http://staff.science.uva.nl/c.dominik/}
@item https
@tab @samp{https://orgmode.org/}
@item doi
@tab @samp{doi:10.1000/182}
@item file
@tab @samp{file:/home/dominik/images/jupiter.jpg}
@item 
@tab @samp{/home/dominik/images/jupiter.jpg} (same as above)
@item 
@tab @samp{file:papers/last.pdf}
@item 
@tab @samp{./papers/last.pdf} (same as above)
@item 
@tab @samp{file:/ssh:me@@some.where:papers/last.pdf} (remote)
@item 
@tab @samp{/ssh:me@@some.where:papers/last.pdf} (same as above)
@item 
@tab @samp{file:sometextfile::NNN} (jump to line number)
@item 
@tab @samp{file:projects.org}
@item 
@tab @samp{file:projects.org::some words} (text search) @footnote{The actual behavior of the search depends on the value of the
variable @code{org-link-search-must-match-exact-headline}.  If its value is
@code{nil}, then a fuzzy text search is done.  If it is @code{t}, then only the
exact headline is matched, ignoring spaces and statistic cookies.  If
the value is @code{query-to-create}, then an exact headline is searched; if
it is not found, then the user is queried to create it.}
@item 
@tab @samp{file:projects.org::*task title} (headline search)
@item 
@tab @samp{file:projects.org::#custom-id} (headline search)
@item attachment
@tab @samp{attachment:projects.org}
@item 
@tab @samp{attachment:projects.org::some words} (text search)
@item docview
@tab @samp{docview:papers/last.pdf::NNN}
@item id
@tab @samp{id:B7423F4D-2E8A-471B-8810-C40F074717E9}
@item news
@tab @samp{news:comp.emacs}
@item mailto
@tab @samp{mailto:adent@@galaxy.net}
@item mhe
@tab @samp{mhe:folder} (folder link)
@item 
@tab @samp{mhe:folder#id} (message link)
@item rmail
@tab @samp{rmail:folder} (folder link)
@item 
@tab @samp{rmail:folder#id} (message link)
@item gnus
@tab @samp{gnus:group} (group link)
@item 
@tab @samp{gnus:group#id} (article link)
@item bbdb
@tab @samp{bbdb:R.*Stallman} (record with regexp)
@item irc
@tab @samp{irc:/irc.com/#emacs/bob}
@item help
@tab @samp{help:org-store-link}
@item info
@tab @samp{info:org#External links}
@item shell
@tab @samp{shell:ls *.org}
@item elisp
@tab @samp{elisp:(find-file "Elisp.org")} (Elisp form to evaluate)
@item 
@tab @samp{elisp:org-agenda} (interactive Elisp command)
@end multitable

@cindex VM links
@cindex Wanderlust links
On top of these built-in link types, additional ones are available
through the @samp{contrib/} directory (see @ref{Installation}).  For example,
these links to VM or Wanderlust messages are available when you load
the corresponding libraries from the @samp{contrib/} directory:

@multitable {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{vm:folder}
@tab VM folder link
@item @samp{vm:folder#id}
@tab VM message link
@item @samp{vm://myself@@some.where.org/folder#id}
@tab VM on remote machine
@item @samp{vm-imap:account:folder}
@tab VM IMAP folder link
@item @samp{vm-imap:account:folder#id}
@tab VM IMAP message link
@item @samp{wl:folder}
@tab Wanderlust folder link
@item @samp{wl:folder#id}
@tab Wanderlust message link
@end multitable

For information on customizing Org to add new link types, see @ref{Adding Hyperlink Types}.

A link should be enclosed in double brackets and may contain
descriptive text to be displayed instead of the URL (see @ref{Link Format}), for example:

@example
[[http://www.gnu.org/software/emacs/][GNU Emacs]]
@end example


If the description is a file name or URL that points to an image, HTML
export (see @ref{HTML Export}) inlines the image as a clickable button.  If
there is no description at all and the link points to an image, that
image is inlined into the exported HTML file.

@cindex square brackets, around links
@cindex angular brackets, around links
@cindex plain text external links
Org also recognizes external links amid normal text and activates them
as links.  If spaces must be part of the link (for example in
@samp{bbdb:R.*Stallman}), or if you need to remove ambiguities about the
end of the link, enclose the link in square or angular brackets.

@node Handling Links
@section Handling Links

@cindex links, handling

Org provides methods to create a link in the correct syntax, to insert
it into an Org file, and to follow the link.

@findex org-store-link
@cindex storing links
The main function is @code{org-store-link}, called with @kbd{M-x org-store-link}.  Because of its importance, we suggest to bind it
to a widely available key (see @ref{Activation}).  It stores a link to the
current location.  The link is stored for later insertion into an Org
buffer---see below.  The kind of link that is created depends on the
current buffer:

@table @asis
@item @emph{Org mode buffers}
For Org files, if there is a @samp{<<target>>} at point, the link points
to the target.  Otherwise it points to the current headline, which
is also the description@footnote{If the headline contains a timestamp, it is removed from the
link, which results in a wrong link---you should avoid putting
a timestamp in the headline.}.

@vindex org-id-link-to-org-use-id
@cindex @samp{CUSTOM_ID}, property
@cindex @samp{ID}, property
If the headline has a @samp{CUSTOM_ID} property, store a link to this
custom ID@.  In addition or alternatively, depending on the value of
@code{org-id-link-to-org-use-id}, create and/or use a globally unique
@samp{ID} property for the link@footnote{The Org Id library must first be loaded, either through
@code{org-customize}, by enabling @code{id} in @code{org-modules}, or by adding
@samp{(require 'org-id)} in your Emacs init file.}.  So using this command in Org
buffers potentially creates two links: a human-readable link from
the custom ID, and one that is globally unique and works even if the
entry is moved from file to file.  Later, when inserting the link,
you need to decide which one to use.

@item @emph{Email/News clients: VM, Rmail, Wanderlust, MH-E, Gnus}
@vindex org-link-email-description-format
Pretty much all Emacs mail clients are supported.  The link points
to the current article, or, in some Gnus buffers, to the group.  The
description is constructed according to the variable
@code{org-link-email-description-format}.  By default, it refers to the
addressee and the subject.

@item @emph{Web browsers: W3, W3M and EWW}
Here the link is the current URL, with the page title as the
description.

@item @emph{Contacts: BBDB}
Links created in a BBDB buffer point to the current entry.

@item @emph{Chat: IRC}
@vindex org-irc-links-to-logs
For IRC links, if the variable @code{org-irc-link-to-logs} is non-@code{nil},
create a @samp{file} style link to the relevant point in the logs for the
current conversation.  Otherwise store an @samp{irc} style link to the
user/channel/server under the point.

@item @emph{Other files}
For any other file, the link points to the file, with a search
string (see @ref{Search Options}) pointing to the contents
of the current line.  If there is an active region, the selected
words form the basis of the search string. You can write custom Lisp
functions to select the search string and perform the search for
particular file types (see @ref{Custom Searches}).

You can also define dedicated links to other files.  See @ref{Adding Hyperlink Types}.

@item @emph{Agenda view}
When point is in an agenda view, the created link points to the
entry referenced by the current line.
@end table

From an Org buffer, the following commands create, navigate or, more
generally, act on links.

@table @asis
@item @kbd{C-c C-l} (@code{org-insert-link})
@kindex C-c C-l
@findex org-insert-link
@cindex link completion
@cindex completion, of links
@cindex inserting links
@vindex org-link-keep-stored-after-insertion
Insert a link@footnote{Note that you do not have to use this command to insert
a link.  Links in Org are plain text, and you can type or paste them
straight into the buffer.  By using this command, the links are
automatically enclosed in double brackets, and you will be asked for
the optional descriptive text.}.  This prompts for a link to be inserted into
the buffer.  You can just type a link, using text for an internal
link, or one of the link type prefixes mentioned in the examples
above.  The link is inserted into the buffer, along with
a descriptive text@footnote{After insertion of a stored link, the link will be removed
from the list of stored links.  To keep it in the list for later use,
use a triple @kbd{C-u} prefix argument to @kbd{C-c C-l}, or
configure the option @code{org-link-keep-stored-after-insertion}.}.  If some text was selected at this time,
it becomes the default description.

@table @asis
@item @emph{Inserting stored links}
All links stored during the current session are part of the
history for this prompt, so you can access them with @kbd{@key{UP}}
and @kbd{@key{DOWN}} (or @kbd{M-p}, @kbd{M-n}).

@item @emph{Completion support}
Completion with @kbd{@key{TAB}} helps you to insert valid link
prefixes like @samp{http} or @samp{ftp}, including the prefixes defined
through link abbreviations (see @ref{Link Abbreviations}).  If you
press @kbd{@key{RET}} after inserting only the prefix, Org offers
specific completion support for some link types@footnote{This works if a function has been defined in the @code{:complete}
property of a link in @code{org-link-parameters}.}.  For
example, if you type @kbd{f i l e @key{RET}}---alternative access:
@kbd{C-u C-c C-l}, see below---Org offers file name
completion, and after @kbd{b b d b @key{RET}} you can complete
contact names.
@end table

@item @kbd{C-u C-c C-l}
@cindex file name completion
@cindex completion, of file names
@kindex C-u C-c C-l
When @kbd{C-c C-l} is called with a @kbd{C-u} prefix
argument, insert a link to a file.  You may use file name completion
to select the name of the file.  The path to the file is inserted
relative to the directory of the current Org file, if the linked
file is in the current directory or in a sub-directory of it, or if
the path is written relative to the current directory using @samp{../}.
Otherwise an absolute path is used, if possible with @samp{~/} for your
home directory.  You can force an absolute path with two
@kbd{C-u} prefixes.

@item @kbd{C-c C-l} (with point on existing link)
@cindex following links
When point is on an existing link, @kbd{C-c C-l} allows you to
edit the link and description parts of the link.

@item @kbd{C-c C-o} (@code{org-open-at-point})
@kindex C-c C-o
@findex org-open-at-point
@vindex org-file-apps
Open link at point.  This launches a web browser for URL (using
@code{browse-url-at-point}), run VM/MH-E/Wanderlust/Rmail/Gnus/BBDB for
the corresponding links, and execute the command in a shell link.
When point is on an internal link, this command runs the
corresponding search.  When point is on the tags part of a headline,
it creates the corresponding tags view (see @ref{Matching tags and properties}).  If point is on a timestamp, it compiles the agenda for
that date.  Furthermore, it visits text and remote files in @samp{file}
links with Emacs and select a suitable application for local
non-text files.  Classification of files is based on file extension
only.  See option @code{org-file-apps}.  If you want to override the
default application and visit the file with Emacs, use
a @kbd{C-u} prefix.  If you want to avoid opening in Emacs, use
a @kbd{C-u C-u} prefix.

@vindex org-link-frame-setup
If point is on a headline, but not on a link, offer all links in the
headline and entry text.  If you want to setup the frame
configuration for following links, customize @code{org-link-frame-setup}.

@item @kbd{@key{RET}}
@vindex org-return-follows-link
@kindex RET
When @code{org-return-follows-link} is set, @kbd{@key{RET}} also follows
the link at point.

@item @kbd{mouse-2} or @kbd{mouse-1}
@kindex mouse-2
@kindex mouse-1
On links, @kbd{mouse-1} and @kbd{mouse-2} opens the link
just as @kbd{C-c C-o} does.

@item @kbd{mouse-3}
@vindex org-link-use-indirect-buffer-for-internals
@kindex mouse-3
Like @kbd{mouse-2}, but force file links to be opened with
Emacs, and internal links to be displayed in another window@footnote{See the variable @code{org-link-use-indirect-buffer-for-internals}.}.

@item @kbd{C-c %} (@code{org-mark-ring-push})
@kindex C-c %
@findex org-mark-ring-push
@cindex mark ring
Push the current position onto the Org mark ring, to be able to
return easily.  Commands following an internal link do this
automatically.

@item @kbd{C-c &} (@code{org-mark-ring-goto})
@kindex C-c &
@findex org-mark-ring-goto
@cindex links, returning to
Jump back to a recorded position.  A position is recorded by the
commands following internal links, and by @kbd{C-c %}.  Using
this command several times in direct succession moves through a ring
of previously recorded positions.

@item @kbd{C-c C-x C-n} (@code{org-next-link})
@itemx @kbd{C-c C-x C-p} (@code{org-previous-link})
@kindex C-c C-x C-p
@findex org-previous-link
@kindex C-c C-x C-n
@findex org-next-link
@cindex links, finding next/previous
Move forward/backward to the next link in the buffer.  At the limit
of the buffer, the search fails once, and then wraps around.  The
key bindings for this are really too long; you might want to bind
this also to @kbd{M-n} and @kbd{M-p}.

@lisp
(add-hook 'org-load-hook
          (lambda ()
            (define-key org-mode-map "\M-n" 'org-next-link)
            (define-key org-mode-map "\M-p" 'org-previous-link)))
@end lisp
@end table

@node Using Links Outside Org
@section Using Links Outside Org

@findex org-insert-link-global
@findex org-open-at-point-global
You can insert and follow links that have Org syntax not only in Org,
but in any Emacs buffer.  For this, Org provides two functions:
@code{org-insert-link-global} and @code{org-open-at-point-global}.

You might want to bind them to globally available keys.  See
@ref{Activation} for some advice.

@node Link Abbreviations
@section Link Abbreviations

@cindex link abbreviations
@cindex abbreviation, links

Long URL can be cumbersome to type, and often many similar links are
needed in a document.  For this you can use link abbreviations.  An
abbreviated link looks like this

@example
[[linkword:tag][description]]
@end example


@noindent
@vindex org-link-abbrev-alist
where the tag is optional.  The @emph{linkword} must be a word, starting
with a letter, followed by letters, numbers, @samp{-}, and @samp{_}.
Abbreviations are resolved according to the information in the
variable @code{org-link-abbrev-alist} that relates the linkwords to
replacement text.  Here is an example:

@lisp
(setq org-link-abbrev-alist
      '(("bugzilla"  . "http://10.1.2.9/bugzilla/show_bug.cgi?id=")
        ("url-to-ja" . "http://translate.google.fr/translate?sl=en&tl=ja&u=%h")
        ("google"    . "http://www.google.com/search?q=")
        ("gmap"      . "http://maps.google.com/maps?q=%s")
        ("omap"      . "http://nominatim.openstreetmap.org/search?q=%s&polygon=1")
        ("ads"       . "https://ui.adsabs.harvard.edu/search/q=%20author%3A\"%s\"")))
@end lisp

If the replacement text contains the string @samp{%s}, it is replaced with
the tag.  Using @samp{%h} instead of @samp{%s} percent-encodes the tag (see the
example above, where we need to encode the URL parameter).  Using
@samp{%(my-function)} passes the tag to a custom Lisp function, and replace
it by the resulting string.

If the replacement text do not contain any specifier, it is simply
appended to the string in order to create the link.

Instead of a string, you may also specify a Lisp function to create
the link.  Such a function will be called with the tag as the only
argument.

With the above setting, you could link to a specific bug with
@samp{[[bugzilla:129]]}, search the web for @samp{OrgMode} with @samp{[[google:OrgMode]]},
show the map location of the Free Software Foundation @samp{[[gmap:51
Franklin Street, Boston]]} or of Carsten office @samp{[[omap:Science Park 904,
Amsterdam, The Netherlands]]} and find out what the Org author is doing
besides Emacs hacking with @samp{[[ads:Dominik,C]]}.

If you need special abbreviations just for a single Org buffer, you
can define them in the file with

@cindex @samp{LINK}, keyword
@example
#+LINK: bugzilla  http://10.1.2.9/bugzilla/show_bug.cgi?id=
#+LINK: google    http://www.google.com/search?q=%s
@end example

In-buffer completion (see @ref{Completion}) can be used after @samp{[} to
complete link abbreviations.  You may also define a Lisp function that
implements special (e.g., completion) support for inserting such a
link with @kbd{C-c C-l}.  Such a function should not accept any
arguments, and should return the full link with a prefix.  You can set
the link completion function like this:

@lisp
(org-link-set-parameter "type" :complete #'some-completion-function)
@end lisp

@node Search Options
@section Search Options in File Links

@cindex search option in file links
@cindex file links, searching
@cindex attachment links, searching

File links can contain additional information to make Emacs jump to a
particular location in the file when following a link.  This can be a
line number or a search option after a double colon@footnote{For backward compatibility, line numbers can also follow a
single colon.}.  For
example, when the command @code{org-store-link} creates a link (see
@ref{Handling Links}) to a file, it encodes the words in the current line
as a search string that can be used to find this line back later when
following the link with @kbd{C-c C-o}.

Note that all search options apply for Attachment links in the same
way that they apply for File links.

Here is the syntax of the different ways to attach a search to a file
link, together with explanations for each:

@example
[[file:~/code/main.c::255]]
[[file:~/xx.org::My Target]]
[[file:~/xx.org::*My Target]]
[[file:~/xx.org::#my-custom-id]]
[[file:~/xx.org::/regexp/]]
[[attachment:main.c::255]]
@end example

@table @asis
@item @samp{255}
Jump to line 255.

@item @samp{My Target}
Search for a link target @samp{<<My Target>>}, or do a text search for
@samp{my target}, similar to the search in internal links, see @ref{Internal Links}.  In HTML export (see @ref{HTML Export}), such a file link becomes
a HTML reference to the corresponding named anchor in the linked
file.

@item @samp{*My Target}
In an Org file, restrict search to headlines.

@item @samp{#my-custom-id}
Link to a heading with a @samp{CUSTOM_ID} property

@item @samp{/REGEXP/}
Do a regular expression search for @var{REGEXP}.  This uses the
Emacs command @code{occur} to list all matches in a separate window.  If
the target file is in Org mode, @code{org-occur} is used to create
a sparse tree with the matches.
@end table

As a degenerate case, a file link with an empty file name can be used
to search the current file.  For example, @samp{[[file:::find me]]} does
a search for @samp{find me} in the current file, just as @samp{[[find me]]}
would.

@node Custom Searches
@section Custom Searches

@cindex custom search strings
@cindex search strings, custom

The default mechanism for creating search strings and for doing the
actual search related to a file link may not work correctly in all
cases.  For example, Bib@TeX{} database files have many entries like
@code{year="1993"} which would not result in good search strings, because
the only unique identification for a Bib@TeX{} entry is the citation key.

@vindex org-create-file-search-functions
@vindex org-execute-file-search-functions
If you come across such a problem, you can write custom functions to
set the right search string for a particular file type, and to do the
search for the string in the file.  Using @code{add-hook}, these functions
need to be added to the hook variables
@code{org-create-file-search-functions} and
@code{org-execute-file-search-functions}.  See the docstring for these
variables for more information.  Org actually uses this mechanism for
Bib@TeX{} database files, and you can use the corresponding code as an
implementation example.  See the file @samp{ol-bibtex.el}.

@node TODO Items
@chapter TODO Items

@cindex TODO items

Org mode does not maintain TODO lists as separate documents@footnote{Of course, you can make a document that contains only long
lists of TODO items, but this is not required.}.
Instead, TODO items are an integral part of the notes file, because
TODO items usually come up while taking notes!  With Org mode, simply
mark any entry in a tree as being a TODO item.  In this way,
information is not duplicated, and the entire context from which the
TODO item emerged is always present.

Of course, this technique for managing TODO items scatters them
throughout your notes file.  Org mode compensates for this by
providing methods to give you an overview of all the things that you
have to do.

@menu
* TODO Basics::                  Marking and displaying TODO entries.
* TODO Extensions::              Workflow and assignments.
* Progress Logging::             Dates and notes for progress.
* Priorities::                   Some things are more important than others.
* Breaking Down Tasks::          Splitting a task into manageable pieces.
* Checkboxes::                   Tick-off lists.
@end menu

@node TODO Basics
@section Basic TODO Functionality

Any headline becomes a TODO item when it starts with the word @samp{TODO},
for example:

@example
*** TODO Write letter to Sam Fortune
@end example


The most important commands to work with TODO entries are:

@table @asis
@item @kbd{C-c C-t} (@code{org-todo})
@kindex C-c C-t
@cindex cycling, of TODO states
Rotate the TODO state of the current item among

@example
,-> (unmarked) -> TODO -> DONE --.
'--------------------------------'
@end example

If TODO keywords have fast access keys (see @ref{Fast access to TODO states}), prompt for a TODO keyword through the fast selection
interface; this is the default behavior when
@code{org-use-fast-todo-selection} is non-@code{nil}.

The same state changing can also be done ``remotely'' from the agenda
buffer with the @kbd{t} command key (see @ref{Agenda Commands}).

@item @kbd{S-@key{RIGHT}} @kbd{S-@key{LEFT}}
@kindex S-RIGHT
@kindex S-LEFT
@vindex org-treat-S-cursor-todo-selection-as-state-change
Select the following/preceding TODO state, similar to cycling.
Useful mostly if more than two TODO states are possible (see
@ref{TODO Extensions}).  See also @ref{Conflicts}, for a discussion of the interaction with
shift-selection.  See also the variable
@code{org-treat-S-cursor-todo-selection-as-state-change}.

@item @kbd{C-c / t} (@code{org-show-todo-tree})
@kindex C-c / t
@cindex sparse tree, for TODO
@vindex org-todo-keywords
@findex org-show-todo-tree
View TODO items in a @emph{sparse tree} (see @ref{Sparse Trees}).  Folds the
entire buffer, but shows all TODO items---with not-DONE state---and
the headings hierarchy above them.  With a prefix argument, or by
using @kbd{C-c / T}, search for a specific TODO@.  You are
prompted for the keyword, and you can also give a list of keywords
like @samp{KWD1|KWD2|...} to list entries that match any one of these
keywords.  With a numeric prefix argument N, show the tree for the
Nth keyword in the variable @code{org-todo-keywords}.  With two prefix
arguments, find all TODO states, both un-done and done.

@item @kbd{M-x org-agenda t} (@code{org-todo-list})
@kindex t @r{(Agenda dispatcher)}
Show the global TODO list.  Collects the TODO items (with not-DONE
states) from all agenda files (see @ref{Agenda Views}) into a single
buffer.  The new buffer is in Org Agenda mode, which provides
commands to examine and manipulate the TODO entries from the new
buffer (see @ref{Agenda Commands}).  See @ref{Global TODO list}, for more information.

@item @kbd{S-M-@key{RET}} (@code{org-insert-todo-heading})
@kindex S-M-RET
@findex org-insert-todo-heading
Insert a new TODO entry below the current one.
@end table

@vindex org-todo-state-tags-triggers
Changing a TODO state can also trigger tag changes.  See the docstring
of the option @code{org-todo-state-tags-triggers} for details.

@node TODO Extensions
@section Extended Use of TODO Keywords

@cindex extended TODO keywords

@vindex org-todo-keywords
By default, marked TODO entries have one of only two states: TODO and
DONE@.  Org mode allows you to classify TODO items in more complex ways
with @emph{TODO keywords} (stored in @code{org-todo-keywords}).  With special
setup, the TODO keyword system can work differently in different
files.

Note that @emph{tags} are another way to classify headlines in general and
TODO items in particular (see @ref{Tags}).

@menu
* Workflow states::              From TODO to DONE in steps.
* TODO types::                   I do this, Fred does the rest.
* Multiple sets in one file::    Mixing it all, still finding your way.
* Fast access to TODO states::   Single letter selection of state.
* Per-file keywords::            Different files, different requirements.
* Faces for TODO keywords::      Highlighting states.
* TODO dependencies::            When one task needs to wait for others.
@end menu

@node Workflow states
@subsection TODO keywords as workflow states

@cindex TODO workflow
@cindex workflow states as TODO keywords

You can use TODO keywords to indicate different, possibly @emph{sequential}
states in the process of working on an item, for example@footnote{Changing the variable @code{org-todo-keywords} only becomes
effective after restarting Org mode in a buffer.}:

@lisp
(setq org-todo-keywords
      '((sequence "TODO" "FEEDBACK" "VERIFY" "|" "DONE" "DELEGATED")))
@end lisp

The vertical bar separates the TODO keywords (states that @emph{need
action}) from the DONE states (which need @emph{no further action}).  If
you do not provide the separator bar, the last state is used as the
DONE state.

@cindex completion, of TODO keywords
With this setup, the command @kbd{C-c C-t} cycles an entry from
@samp{TODO} to @samp{FEEDBACK}, then to @samp{VERIFY}, and finally to @samp{DONE} and
@samp{DELEGATED}.  You may also use a numeric prefix argument to quickly
select a specific state.  For example @kbd{C-3 C-c C-t} changes
the state immediately to @samp{VERIFY}.  Or you can use @kbd{S-@key{RIGHT}}
and @kbd{S-@key{LEFT}} to go forward and backward through the states.
If you define many keywords, you can use in-buffer completion (see
@ref{Completion}) or a special one-key selection scheme (see @ref{Fast access to TODO states}) to insert these words into the buffer.
Changing a TODO state can be logged with a timestamp, see @ref{Tracking TODO state changes}, for more information.

@node TODO types
@subsection TODO keywords as types

@cindex TODO types
@cindex names as TODO keywords
@cindex types as TODO keywords

The second possibility is to use TODO keywords to indicate different
@emph{types} of action items.  For example, you might want to indicate that
items are for ``work'' or ``home''.  Or, when you work with several people
on a single project, you might want to assign action items directly to
persons, by using their names as TODO keywords.  This type of
functionality is actually much better served by using tags (see
@ref{Tags}), so the TODO implementation is kept just for backward
compatibility.

Using TODO types, it would be set up like this:

@lisp
(setq org-todo-keywords '((type "Fred" "Sara" "Lucy" "|" "DONE")))
@end lisp

In this case, different keywords do not indicate states, but
rather different types.  So the normal work flow would be to assign
a task to a person, and later to mark it DONE@.  Org mode supports this
style by adapting the workings of the command @kbd{C-c C-t}@footnote{This is also true for the @kbd{t} command in the agenda
buffer.}.  When used several times in succession, it still
cycles through all names, in order to first select the right type for
a task.  But when you return to the item after some time and execute
@kbd{C-c C-t} again, it will switch from any name directly to
@samp{DONE}.  Use prefix arguments or completion to quickly select
a specific name.  You can also review the items of a specific TODO
type in a sparse tree by using a numeric prefix to @kbd{C-c / t}.
For example, to see all things Lucy has to do, you would use
@kbd{C-3 C-c / t}.  To collect Lucy's items from all agenda files
into a single buffer, you would use the numeric prefix argument as
well when creating the global TODO list: @kbd{C-3 M-x org-agenda t}.

@node Multiple sets in one file
@subsection Multiple keyword sets in one file

@cindex TODO keyword sets

Sometimes you may want to use different sets of TODO keywords in
parallel.  For example, you may want to have the basic TODO/DONE, but
also a workflow for bug fixing, and a separate state indicating that
an item has been canceled---so it is not DONE, but also does not
require action.  Your setup would then look like this:

@lisp
(setq org-todo-keywords
      '((sequence "TODO" "|" "DONE")
        (sequence "REPORT" "BUG" "KNOWNCAUSE" "|" "FIXED")
        (sequence "|" "CANCELED")))
@end lisp

The keywords should all be different, this helps Org mode keep track
of which subsequence should be used for a given entry.  In this setup,
@kbd{C-c C-t} only operates within a sub-sequence, so it switches
from @samp{DONE} to (nothing) to @samp{TODO}, and from @samp{FIXED} to (nothing) to
@samp{REPORT}.  Therefore you need a mechanism to initially select the
correct sequence.  In addition to typing a keyword or using completion
(see @ref{Completion}), you may also apply the following commands:

@table @asis
@item @kbd{C-u C-u C-c C-t}
@itemx @kbd{C-S-@key{RIGHT}}
@itemx @kbd{C-S-@key{LEFT}}
@kindex C-S-RIGHT
@kindex C-S-LEFT
@kindex C-u C-u C-c C-t
These keys jump from one TODO sub-sequence to the next.  In the
above example, @kbd{C-u C-u C-c C-t} or @kbd{C-S-@key{RIGHT}}
would jump from @samp{TODO} or @samp{DONE} to @samp{REPORT}, and any of the words
in the second row to @samp{CANCELED}.  Note that the @kbd{C-S-} key
binding conflict with shift-selection (see @ref{Conflicts}).

@item @kbd{S-@key{RIGHT}}
@itemx @kbd{S-@key{LEFT}}
@kindex S-RIGHT
@kindex S-LEFT
@kbd{S-@key{LEFT}} and @kbd{S-@key{RIGHT}} walk through @emph{all} keywords
from all sub-sequences, so for example @kbd{S-@key{RIGHT}} would
switch from @samp{DONE} to @samp{REPORT} in the example above.  For
a discussion of the interaction with shift-selection, see @ref{Conflicts}.
@end table

@node Fast access to TODO states
@subsection Fast access to TODO states

If you would like to quickly change an entry to an arbitrary TODO
state instead of cycling through the states, you can set up keys for
single-letter access to the states.  This is done by adding the
selection character after each keyword, in parentheses@footnote{All characters are allowed except @samp{@@}, @samp{^} and @samp{!}, which have
a special meaning here.}.  For
example:

@lisp
(setq org-todo-keywords
      '((sequence "TODO(t)" "|" "DONE(d)")
        (sequence "REPORT(r)" "BUG(b)" "KNOWNCAUSE(k)" "|" "FIXED(f)")
        (sequence "|" "CANCELED(c)")))
@end lisp

@vindex org-fast-tag-selection-include-todo
If you then press @kbd{C-c C-t} followed by the selection key,
the entry is switched to this state.  @kbd{@key{SPC}} can be used to
remove any TODO keyword from an entry@footnote{Check also the variable @code{org-fast-tag-selection-include-todo},
it allows you to change the TODO state through the tags interface (see
@ref{Setting Tags}), in case you like to mingle the two concepts.  Note
that this means you need to come up with unique keys across both sets
of keywords.}.

@node Per-file keywords
@subsection Setting up keywords for individual files

@cindex keyword options
@cindex per-file keywords
@cindex @samp{TODO}, keyword
@cindex @samp{TYP_TODO}, keyword
@cindex @samp{SEQ_TODO}, keyword

It can be very useful to use different aspects of the TODO mechanism
in different files.  For file-local settings, you need to add special
lines to the file which set the keywords and interpretation for that
file only.  For example, to set one of the two examples discussed
above, you need one of the following lines, starting in column zero
anywhere in the file:

@example
#+TODO: TODO FEEDBACK VERIFY | DONE CANCELED
@end example


You may also write @samp{#+SEQ_TODO} to be explicit about the
interpretation, but it means the same as @samp{#+TODO}, or

@example
#+TYP_TODO: Fred Sara Lucy Mike | DONE
@end example


A setup for using several sets in parallel would be:

@example
#+TODO: TODO | DONE
#+TODO: REPORT BUG KNOWNCAUSE | FIXED
#+TODO: | CANCELED
@end example

@cindex completion, of option keywords
@kindex M-TAB
To make sure you are using the correct keyword, type @samp{#+} into the
buffer and then use @kbd{M-@key{TAB}} to complete it (see @ref{Completion}).

@cindex DONE, final TODO keyword
Remember that the keywords after the vertical bar---or the last
keyword if no bar is there---must always mean that the item is DONE,
although you may use a different word.  After changing one of these
lines, use @kbd{C-c C-c} with point still in the line to make the
changes known to Org mode@footnote{Org mode parses these lines only when Org mode is activated
after visiting a file.  @kbd{C-c C-c} with point in a line
starting with @samp{#+} is simply restarting Org mode for the current
buffer.}.

@node Faces for TODO keywords
@subsection Faces for TODO keywords

@cindex faces, for TODO keywords

@vindex org-todo, face
@vindex org-done, face
@vindex org-todo-keyword-faces
Org mode highlights TODO keywords with special faces: @code{org-todo} for
keywords indicating that an item still has to be acted upon, and
@code{org-done} for keywords indicating that an item is finished.  If you
are using more than two different states, you might want to use
special faces for some of them.  This can be done using the variable
@code{org-todo-keyword-faces}.  For example:

@lisp
(setq org-todo-keyword-faces
      '(("TODO" . org-warning) ("STARTED" . "yellow")
        ("CANCELED" . (:foreground "blue" :weight bold))))
@end lisp

@vindex org-faces-easy-properties
While using a list with face properties as shown for @samp{CANCELED}
@emph{should} work, this does not always seem to be the case.  If
necessary, define a special face and use that.  A string is
interpreted as a color.  The variable @code{org-faces-easy-properties}
determines if that color is interpreted as a foreground or
a background color.

@node TODO dependencies
@subsection TODO dependencies

@cindex TODO dependencies
@cindex dependencies, of TODO states

@vindex org-enforce-todo-dependencies
@cindex @samp{ORDERED}, property
The structure of Org files---hierarchy and lists---makes it easy to
define TODO dependencies.  Usually, a parent TODO task should not be
marked as done until all TODO subtasks, or children tasks, are marked
as done.  Sometimes there is a logical sequence to (sub)tasks, so that
one subtask cannot be acted upon before all siblings above it have
been marked as done.  If you customize the variable
@code{org-enforce-todo-dependencies}, Org blocks entries from changing
state to DONE while they have TODO children that are not DONE@.
Furthermore, if an entry has a property @samp{ORDERED}, each of its TODO
children is blocked until all earlier siblings are marked as done.
Here is an example:

@example
* TODO Blocked until (two) is done
** DONE one
** TODO two

* Parent
:PROPERTIES:
:ORDERED:  t
:END:
** TODO a
** TODO b, needs to wait for (a)
** TODO c, needs to wait for (a) and (b)
@end example

@cindex TODO dependencies, @samp{NOBLOCKING}
@cindex @samp{NOBLOCKING}, property
You can ensure an entry is never blocked by using the @samp{NOBLOCKING}
property (see @ref{Properties and Columns}):

@example
* This entry is never blocked
:PROPERTIES:
:NOBLOCKING: t
:END:
@end example

@table @asis
@item @kbd{C-c C-x o} (@code{org-toggle-ordered-property})
@kindex C-c C-x o
@findex org-toggle-ordered-property
@vindex org-track-ordered-property-with-tag
Toggle the @samp{ORDERED} property of the current entry.  A property is
used for this behavior because this should be local to the current
entry, not inherited from entries above like a tag (see @ref{Tags}).
However, if you would like to @emph{track} the value of this property
with a tag for better visibility, customize the variable
@code{org-track-ordered-property-with-tag}.

@item @kbd{C-u C-u C-u C-c C-t}
@kindex C-u C-u C-u C-u C-c C-t
Change TODO state, regardless of any state blocking.
@end table

@vindex org-agenda-dim-blocked-tasks
If you set the variable @code{org-agenda-dim-blocked-tasks}, TODO entries
that cannot be marked as done because of unmarked children are shown
in a dimmed font or even made invisible in agenda views (see @ref{Agenda Views}).

@cindex checkboxes and TODO dependencies
@vindex org-enforce-todo-dependencies
You can also block changes of TODO states by using checkboxes (see
@ref{Checkboxes}).  If you set the variable
@code{org-enforce-todo-checkbox-dependencies}, an entry that has unchecked
checkboxes is blocked from switching to DONE@.

If you need more complex dependency structures, for example
dependencies between entries in different trees or files, check out
the contributed module @samp{org-depend.el}.

@node Progress Logging
@section Progress Logging

@cindex progress logging
@cindex logging, of progress

To record a timestamp and a note when changing a TODO state, call the
command @code{org-todo} with a prefix argument.

@table @asis
@item @kbd{C-u C-c C-t} (@code{org-todo})
@kindex C-u C-c C-t
Prompt for a note and record a the time of the TODO state change.
The note is inserted as a list item below the headline, but can also
be placed into a drawer, see @ref{Tracking TODO state changes}.
@end table

If you want to be more systematic, Org mode can automatically record a
timestamp and optionally a note when you mark a TODO item as DONE, or
even each time you change the state of a TODO item.  This system is
highly configurable, settings can be on a per-keyword basis and can be
localized to a file or even a subtree.  For information on how to
clock working time for a task, see @ref{Clocking Work Time}.

@menu
* Closing items::                When was this entry marked as done?
* Tracking TODO state changes::  When did the status change?
* Tracking your habits::         How consistent have you been?
@end menu

@node Closing items
@subsection Closing items

The most basic automatic logging is to keep track of @emph{when} a certain
TODO item was marked as done.  This can be achieved with@footnote{The corresponding in-buffer setting is: @samp{#+STARTUP: logdone}.}

@lisp
(setq org-log-done 'time)
@end lisp

@vindex org-closed-keep-when-no-todo
@noindent
Then each time you turn an entry from a TODO (not-done) state into any
of the DONE states, a line @samp{CLOSED: [timestamp]} is inserted just
after the headline.  If you turn the entry back into a TODO item
through further state cycling, that line is removed again.  If you
turn the entry back to a non-TODO state (by pressing @kbd{C-c C-t @key{SPC}} for example), that line is also removed, unless you set
@code{org-closed-keep-when-no-todo} to non-@code{nil}.  If you want to record
a note along with the timestamp, use@footnote{The corresponding in-buffer setting is: @samp{#+STARTUP:
lognotedone}.}

@lisp
(setq org-log-done 'note)
@end lisp

@noindent
You are then prompted for a note, and that note is stored below the
entry with a @samp{Closing Note} heading.

@node Tracking TODO state changes
@subsection Tracking TODO state changes

@cindex drawer, for state change recording

@vindex org-log-states-order-reversed
@vindex org-log-into-drawer
@cindex @samp{LOG_INTO_DRAWER}, property
You might want to automatically keep track of when a state change
occurred and maybe take a note about this change.  You can either
record just a timestamp, or a time-stamped note.  These records are
inserted after the headline as an itemized list, newest first@footnote{See the variable @code{org-log-states-order-reversed}.}.
When taking a lot of notes, you might want to get the notes out of the
way into a drawer (see @ref{Drawers}).  Customize the variable
@code{org-log-into-drawer} to get this behavior---the recommended drawer
for this is called @samp{LOGBOOK}@footnote{Note that the @samp{LOGBOOK} drawer is unfolded when pressing
@kbd{@key{SPC}} in the agenda to show an entry---use @kbd{C-u @key{SPC}} to keep it folded here.}.  You can also overrule the
setting of this variable for a subtree by setting a @samp{LOG_INTO_DRAWER}
property.

Since it is normally too much to record a note for every state, Org
mode expects configuration on a per-keyword basis for this.  This is
achieved by adding special markers @samp{!} (for a timestamp) or @samp{@@} (for
a note with timestamp) in parentheses after each keyword.  For
example, with the setting

@lisp
(setq org-todo-keywords
      '((sequence "TODO(t)" "WAIT(w@@/!)" "|" "DONE(d!)" "CANCELED(c@@)")))
@end lisp

@noindent
To record a timestamp without a note for TODO keywords configured with
@samp{@@}, just type @kbd{C-c C-c} to enter a blank note when prompted.

@vindex org-log-done
You not only define global TODO keywords and fast access keys, but
also request that a time is recorded when the entry is set to @samp{DONE},
and that a note is recorded when switching to @samp{WAIT} or
@samp{CANCELED}@footnote{It is possible that Org mode records two timestamps when you
are using both @code{org-log-done} and state change logging.  However, it
never prompts for two notes: if you have configured both, the state
change recording note takes precedence and cancel the closing note.}.  The setting for @samp{WAIT} is even more special: the
@samp{!} after the slash means that in addition to the note taken when
entering the state, a timestamp should be recorded when @emph{leaving} the
@samp{WAIT} state, if and only if the @emph{target} state does not configure
logging for entering it.  So it has no effect when switching from
@samp{WAIT} to @samp{DONE}, because @samp{DONE} is configured to record a timestamp
only.  But when switching from @samp{WAIT} back to @samp{TODO}, the @samp{/!} in the
@samp{WAIT} setting now triggers a timestamp even though @samp{TODO} has no
logging configured.

You can use the exact same syntax for setting logging preferences local
to a buffer:

@example
#+TODO: TODO(t) WAIT(w@@/!) | DONE(d!) CANCELED(c@@)
@end example


@cindex @samp{LOGGING}, property
In order to define logging settings that are local to a subtree or
a single item, define a @samp{LOGGING} property in this entry.  Any
non-empty @samp{LOGGING} property resets all logging settings to @code{nil}.
You may then turn on logging for this specific tree using @samp{STARTUP}
keywords like @samp{lognotedone} or @samp{logrepeat}, as well as adding state
specific settings like @samp{TODO(!)}.  For example:

@example
* TODO Log each state with only a time
  :PROPERTIES:
  :LOGGING: TODO(!) WAIT(!) DONE(!) CANCELED(!)
  :END:
* TODO Only log when switching to WAIT, and when repeating
  :PROPERTIES:
  :LOGGING: WAIT(@@) logrepeat
  :END:
* TODO No logging at all
  :PROPERTIES:
  :LOGGING: nil
  :END:
@end example

@node Tracking your habits
@subsection Tracking your habits

@cindex habits
@cindex @samp{STYLE}, property

Org has the ability to track the consistency of a special category of
TODO, called ``habits.''  To use habits, you have to enable the @code{habits}
module by customizing the variable @code{org-modules}.

A habit has the following properties:

@enumerate
@item
The habit is a TODO item, with a TODO keyword representing an open
state.

@item
The property @samp{STYLE} is set to the value @samp{habit} (see @ref{Properties and Columns}).

@item
The TODO has a scheduled date, usually with a @samp{.+} style repeat
interval.  A @samp{++} style may be appropriate for habits with time
constraints, e.g., must be done on weekends, or a @samp{+} style for an
unusual habit that can have a backlog, e.g., weekly reports.

@item
The TODO may also have minimum and maximum ranges specified by
using the syntax @samp{.+2d/3d}, which says that you want to do the task
at least every three days, but at most every two days.

@item
State logging for the DONE state is enabled (see @ref{Tracking TODO state changes}), in order for historical data to be represented in
the consistency graph.  If it is not enabled it is not an error,
but the consistency graphs are largely meaningless.
@end enumerate

To give you an idea of what the above rules look like in action, here's an
actual habit with some history:

@example
** TODO Shave
   SCHEDULED: <2009-10-17 Sat .+2d/4d>
   :PROPERTIES:
   :STYLE:    habit
   :LAST_REPEAT: [2009-10-19 Mon 00:36]
   :END:
   - State "DONE"       from "TODO"       [2009-10-15 Thu]
   - State "DONE"       from "TODO"       [2009-10-12 Mon]
   - State "DONE"       from "TODO"       [2009-10-10 Sat]
   - State "DONE"       from "TODO"       [2009-10-04 Sun]
   - State "DONE"       from "TODO"       [2009-10-02 Fri]
   - State "DONE"       from "TODO"       [2009-09-29 Tue]
   - State "DONE"       from "TODO"       [2009-09-25 Fri]
   - State "DONE"       from "TODO"       [2009-09-19 Sat]
   - State "DONE"       from "TODO"       [2009-09-16 Wed]
   - State "DONE"       from "TODO"       [2009-09-12 Sat]
@end example

What this habit says is: I want to shave at most every 2 days---given
by the @samp{SCHEDULED} date and repeat interval---and at least every
4 days.  If today is the 15th, then the habit first appears in the
agenda (see @ref{Agenda Views}) on Oct 17, after the minimum of 2 days has
elapsed, and will appear overdue on Oct 19, after four days have
elapsed.

What's really useful about habits is that they are displayed along
with a consistency graph, to show how consistent you've been at
getting that task done in the past.  This graph shows every day that
the task was done over the past three weeks, with colors for each day.
The colors used are:

@table @asis
@item Blue
If the task was not to be done yet on that day.
@item Green
If the task could have been done on that day.
@item Yellow
If the task was going to be overdue the next day.
@item Red
If the task was overdue on that day.
@end table

In addition to coloring each day, the day is also marked with an
asterisk if the task was actually done that day, and an exclamation
mark to show where the current day falls in the graph.

There are several configuration variables that can be used to change
the way habits are displayed in the agenda.

@table @asis
@item @code{org-habit-graph-column}
@vindex org-habit-graph-column
The buffer column at which the consistency graph should be drawn.
This overwrites any text in that column, so it is a good idea to
keep your habits' titles brief and to the point.

@item @code{org-habit-preceding-days}
@vindex org-habit-preceding-days
The amount of history, in days before today, to appear in
consistency graphs.

@item @code{org-habit-following-days}
@vindex org-habit-following-days
The number of days after today that appear in consistency graphs.

@item @code{org-habit-show-habits-only-for-today}
@vindex org-habit-show-habits-only-for-today
If non-@code{nil}, only show habits in today's agenda view.  The default
value is @code{t}.  Pressing @kbd{C-u K} in the agenda toggles this
variable.
@end table

Lastly, pressing @kbd{K} in the agenda buffer causes habits to
temporarily be disabled and do not appear at all.  Press @kbd{K}
again to bring them back.  They are also subject to tag filtering, if
you have habits which should only be done in certain contexts, for
example.

@node Priorities
@section Priorities

@cindex priorities
@cindex priority cookie

If you use Org mode extensively, you may end up with enough TODO items
that it starts to make sense to prioritize them.  Prioritizing can be
done by placing a @emph{priority cookie} into the headline of a TODO item,
like this

@example
*** TODO [#A] Write letter to Sam Fortune
@end example


@vindex org-priority-faces
By default, Org mode supports three priorities: @samp{A}, @samp{B}, and @samp{C}.
@samp{A} is the highest priority.  An entry without a cookie is treated as
equivalent if it had priority @samp{B}.  Priorities make a difference only
for sorting in the agenda (see @ref{Weekly/daily agenda}); outside the
agenda, they have no inherent meaning to Org mode.  The cookies are
displayed with the face defined by the variable @code{org-priority-faces},
which can be customized.

Priorities can be attached to any outline node; they do not need to be
TODO items.

@table @asis
@item @kbd{C-c ,} (@code{org-priority})
@kindex C-c ,
@findex org-priority
Set the priority of the current headline.  The command prompts for
a priority character @samp{A}, @samp{B} or @samp{C}.  When you press @kbd{@key{SPC}}
instead, the priority cookie, if one is set, is removed from the
headline.  The priorities can also be changed ``remotely'' from the
agenda buffer with the @kbd{,} command (see @ref{Agenda Commands}).

@item @kbd{S-@key{UP}} (@code{org-priority-up})
@itemx @kbd{S-@key{DOWN}} (@code{org-priority-down})
@kindex S-UP
@kindex S-DOWN
@findex org-priority-up
@findex org-priority-down
@vindex org-priority-start-cycle-with-default
Increase/decrease the priority of the current headline@footnote{See also the option @code{org-priority-start-cycle-with-default}.}.  Note
that these keys are also used to modify timestamps (see @ref{Creating Timestamps}).  See also @ref{Conflicts}, for
a discussion of the interaction with shift-selection.
@end table

@vindex org-highest-priority
@vindex org-lowest-priority
@vindex org-default-priority
You can change the range of allowed priorities by setting the
variables @code{org-highest-priority}, @code{org-lowest-priority}, and
@code{org-default-priority}.  For an individual buffer, you may set these
values (highest, lowest, default) like this (please make sure that the
highest priority is earlier in the alphabet than the lowest priority):

@cindex @samp{PRIORITIES}, keyword
@example
#+PRIORITIES: A C B
@end example

@node Breaking Down Tasks
@section Breaking Down Tasks into Subtasks

@cindex tasks, breaking down
@cindex statistics, for TODO items

@vindex org-agenda-todo-list-sublevels
It is often advisable to break down large tasks into smaller,
manageable subtasks.  You can do this by creating an outline tree
below a TODO item, with detailed subtasks on the tree@footnote{To keep subtasks out of the global TODO list, see the option
@code{org-agenda-todo-list-sublevels}.}.  To keep
an overview of the fraction of subtasks that have already been marked
as done, insert either @samp{[/]} or @samp{[%]} anywhere in the headline.  These
cookies are updated each time the TODO status of a child changes, or
when pressing @kbd{C-c C-c} on the cookie.  For example:

@example
* Organize Party [33%]
** TODO Call people [1/2]
*** TODO Peter
*** DONE Sarah
** TODO Buy food
** DONE Talk to neighbor
@end example

@cindex @samp{COOKIE_DATA}, property
If a heading has both checkboxes and TODO children below it, the
meaning of the statistics cookie become ambiguous.  Set the property
@samp{COOKIE_DATA} to either @samp{checkbox} or @samp{todo} to resolve this issue.

@vindex org-hierarchical-todo-statistics
If you would like to have the statistics cookie count any TODO entries
in the subtree (not just direct children), configure the variable
@code{org-hierarchical-todo-statistics}.  To do this for a single subtree,
include the word @samp{recursive} into the value of the @samp{COOKIE_DATA}
property.

@example
* Parent capturing statistics [2/20]
  :PROPERTIES:
  :COOKIE_DATA: todo recursive
  :END:
@end example

If you would like a TODO entry to automatically change to DONE when
all children are done, you can use the following setup:

@lisp
(defun org-summary-todo (n-done n-not-done)
  "Switch entry to DONE when all subentries are done, to TODO otherwise."
  (let (org-log-done org-log-states)   ; turn off logging
    (org-todo (if (= n-not-done 0) "DONE" "TODO"))))

(add-hook 'org-after-todo-statistics-hook 'org-summary-todo)
@end lisp

Another possibility is the use of checkboxes to identify (a hierarchy
of) a large number of subtasks (see @ref{Checkboxes}).

@node Checkboxes
@section Checkboxes

@cindex checkboxes

@vindex org-list-automatic-rules
Every item in a plain list@footnote{With the exception of description lists.  But you can allow it
by modifying @code{org-list-automatic-rules} accordingly.} (see @ref{Plain Lists}) can be made into
a checkbox by starting it with the string @samp{[ ]}.  This feature is
similar to TODO items (see @ref{TODO Items}), but is more lightweight.
Checkboxes are not included into the global TODO list, so they are
often great to split a task into a number of simple steps.  Or you can
use them in a shopping list.

Here is an example of a checkbox list.

@example
* TODO Organize party [2/4]
  - [-] call people [1/3]
    - [ ] Peter
    - [X] Sarah
    - [ ] Sam
  - [X] order food
  - [ ] think about what music to play
  - [X] talk to the neighbors
@end example

Checkboxes work hierarchically, so if a checkbox item has children
that are checkboxes, toggling one of the children checkboxes makes the
parent checkbox reflect if none, some, or all of the children are
checked.

@cindex statistics, for checkboxes
@cindex checkbox statistics
@cindex @samp{COOKIE_DATA}, property
@vindex org-hierarchical-checkbox-statistics
The @samp{[2/4]} and @samp{[1/3]} in the first and second line are cookies
indicating how many checkboxes present in this entry have been checked
off, and the total number of checkboxes present.  This can give you an
idea on how many checkboxes remain, even without opening a folded
entry.  The cookies can be placed into a headline or into (the first
line of) a plain list item.  Each cookie covers checkboxes of direct
children structurally below the headline/item on which the cookie
appears@footnote{Set the variable @code{org-hierarchical-checkbox-statistics} if you
want such cookies to count all checkboxes below the cookie, not just
those belonging to direct children.}.  You have to insert the cookie yourself by typing
either @samp{[/]} or @samp{[%]}.  With @samp{[/]} you get an @samp{n out of m} result, as
in the examples above.  With @samp{[%]} you get information about the
percentage of checkboxes checked (in the above example, this would be
@samp{[50%]} and @samp{[33%]}, respectively).  In a headline, a cookie can count
either checkboxes below the heading or TODO states of children, and it
displays whatever was changed last.  Set the property @samp{COOKIE_DATA} to
either @samp{checkbox} or @samp{todo} to resolve this issue.

@cindex blocking, of checkboxes
@cindex checkbox blocking
@cindex @samp{ORDERED}, property
If the current outline node has an @samp{ORDERED} property, checkboxes must
be checked off in sequence, and an error is thrown if you try to check
off a box while there are unchecked boxes above it.

The following commands work with checkboxes:

@table @asis
@item @kbd{C-c C-c} (@code{org-toggle-checkbox})
@kindex C-c C-c
@findex org-toggle-checkbox
Toggle checkbox status or---with prefix argument---checkbox presence
at point.  With a single prefix argument, add an empty checkbox or
remove the current one@footnote{@kbd{C-u C-c C-c} on the @emph{first} item of a list with no
checkbox adds checkboxes to the rest of the list.}.  With a double prefix argument, set
it to @samp{[-]}, which is considered to be an intermediate state.

@item @kbd{C-c C-x C-b} (@code{org-toggle-checkbox})
@kindex C-c C-x C-b
Toggle checkbox status or---with prefix argument---checkbox presence
at point.  With double prefix argument, set it to @samp{[-]}, which is
considered to be an intermediate state.

@itemize
@item
If there is an active region, toggle the first checkbox in the
region and set all remaining boxes to the same status as the
first.  With a prefix argument, add or remove the checkbox for all
items in the region.

@item
If point is in a headline, toggle checkboxes in the region between
this headline and the next---so @emph{not} the entire subtree.

@item
If there is no active region, just toggle the checkbox at point.
@end itemize

@item @kbd{M-S-@key{RET}} (@code{org-insert-todo-heading})
@kindex M-S-RET
@findex org-insert-todo-heading
Insert a new item with a checkbox.  This works only if point is
already in a plain list item (see @ref{Plain Lists}).

@item @kbd{C-c C-x o} (@code{org-toggle-ordered-property})
@kindex C-c C-x o
@findex org-toggle-ordered-property
@vindex org-track-ordered-property-with-tag
Toggle the @samp{ORDERED} property of the entry, to toggle if checkboxes
must be checked off in sequence.  A property is used for this
behavior because this should be local to the current entry, not
inherited like a tag.  However, if you would like to @emph{track} the
value of this property with a tag for better visibility, customize
@code{org-track-ordered-property-with-tag}.

@item @kbd{C-c #} (@code{org-update-statistics-cookies})
@kindex C-c #
@findex org-update-statistics-cookies
Update the statistics cookie in the current outline entry.  When
called with a @kbd{C-u} prefix, update the entire file.
Checkbox statistic cookies are updated automatically if you toggle
checkboxes with @kbd{C-c C-c} and make new ones with
@kbd{M-S-@key{RET}}.  TODO statistics cookies update when changing
TODO states.  If you delete boxes/entries or add/change them by
hand, use this command to get things back into sync.
@end table

@node Tags
@chapter Tags

@cindex tags
@cindex headline tagging
@cindex matching, tags
@cindex sparse tree, tag based

An excellent way to implement labels and contexts for
cross-correlating information is to assign @emph{tags} to headlines.  Org
mode has extensive support for tags.

@vindex org-tag-faces
Every headline can contain a list of tags; they occur at the end of
the headline.  Tags are normal words containing letters, numbers, @samp{_},
and @samp{@@}.  Tags must be preceded and followed by a single colon, e.g.,
@samp{:work:}.  Several tags can be specified, as in @samp{:work:urgent:}.  Tags
by default are in bold face with the same color as the headline.  You
may specify special faces for specific tags using the variable
@code{org-tag-faces}, in much the same way as you can for TODO keywords
(see @ref{Faces for TODO keywords}).

@menu
* Tag Inheritance::              Tags use the tree structure of an outline.
* Setting Tags::                 How to assign tags to a headline.
* Tag Hierarchy::                Create a hierarchy of tags.
* Tag Searches::                 Searching for combinations of tags.
@end menu

@node Tag Inheritance
@section Tag Inheritance

@cindex tag inheritance
@cindex inheritance, of tags
@cindex sublevels, inclusion into tags match

@emph{Tags} make use of the hierarchical structure of outline trees.  If
a heading has a certain tag, all subheadings inherit the tag as well.
For example, in the list

@example
* Meeting with the French group      :work:
** Summary by Frank                  :boss:notes:
*** TODO Prepare slides for him      :action:
@end example

@noindent
the final heading has the tags @samp{work}, @samp{boss}, @samp{notes}, and @samp{action}
even though the final heading is not explicitly marked with those
tags.  You can also set tags that all entries in a file should inherit
just as if these tags were defined in a hypothetical level zero that
surrounds the entire file.  Use a line like this@footnote{As with all these in-buffer settings, pressing @kbd{C-c C-c} activates any changes in the line.}

@cindex @samp{FILETAGS}, keyword
@example
#+FILETAGS: :Peter:Boss:Secret:
@end example


@vindex org-use-tag-inheritance
@vindex org-tags-exclude-from-inheritance
To limit tag inheritance to specific tags, or to turn it off entirely,
use the variables @code{org-use-tag-inheritance} and
@code{org-tags-exclude-from-inheritance}.

@vindex org-tags-match-list-sublevels
When a headline matches during a tags search while tag inheritance is
turned on, all the sublevels in the same tree---for a simple match
form---match as well@footnote{This is only true if the search does not involve more complex
tests including properties (see @ref{Property Searches}).}.  The list of matches may then become
very long.  If you only want to see the first tags match in a subtree,
configure the variable @code{org-tags-match-list-sublevels} (not
recommended).

@vindex org-agenda-use-tag-inheritance
Tag inheritance is relevant when the agenda search tries to match
a tag, either in the @code{tags} or @code{tags-todo} agenda types.  In other
agenda types, @code{org-use-tag-inheritance} has no effect.  Still, you may
want to have your tags correctly set in the agenda, so that tag
filtering works fine, with inherited tags.  Set
@code{org-agenda-use-tag-inheritance} to control this: the default value
includes all agenda types, but setting this to @code{nil} can really speed
up agenda generation.

@node Setting Tags
@section Setting Tags

@cindex setting tags
@cindex tags, setting

@kindex M-TAB
Tags can simply be typed into the buffer at the end of a headline.
After a colon, @kbd{M-@key{TAB}} offers completion on tags.  There is
also a special command for inserting tags:

@table @asis
@item @kbd{C-c C-q} (@code{org-set-tags-command})
@kindex C-c C-q
@findex org-set-tags-command
@cindex completion, of tags
@vindex org-tags-column
Enter new tags for the current headline.  Org mode either offers
completion or a special single-key interface for setting tags, see
below.  After pressing @kbd{@key{RET}}, the tags are inserted and
aligned to @code{org-tags-column}.  When called with a @kbd{C-u}
prefix, all tags in the current buffer are aligned to that column,
just to make things look nice.  Tags are automatically realigned
after promotion, demotion, and TODO state changes (see @ref{TODO Basics}).

@item @kbd{C-c C-c} (@code{org-set-tags-command})
@kindex C-c C-c
When point is in a headline, this does the same as @kbd{C-c C-q}.
@end table

@vindex org-complete-tags-always-offer-all-agenda-tags
@vindex org-tag-alist
@cindex @samp{TAGS}, keyword
Org supports tag insertion based on a @emph{list of tags}.  By default this
list is constructed dynamically, containing all tags currently used in
the buffer@footnote{To extend this default list to all tags used in all agenda
files (see @ref{Agenda Views}), customize the variable
@code{org-complete-tags-always-offer-all-agenda-tags}.}.  You may also globally specify a hard list of tags
with the variable @code{org-tag-alist}.  Finally you can set the default
tags for a given file using the @samp{TAGS} keyword, like

@example
#+TAGS: @@work @@home @@tennisclub
#+TAGS: laptop car pc sailboat
@end example

If you have globally defined your preferred set of tags using the
variable @code{org-tag-alist}, but would like to use a dynamic tag list in
a specific file, add an empty @samp{TAGS} keyword to that file:

@example
#+TAGS:
@end example


@vindex org-tag-persistent-alist
If you have a preferred set of tags that you would like to use in
every file, in addition to those defined on a per-file basis by @samp{TAGS}
keyword, then you may specify a list of tags with the variable
@code{org-tag-persistent-alist}.  You may turn this off on a per-file basis
by adding a @samp{STARTUP} keyword to that file:

@example
#+STARTUP: noptag
@end example


By default Org mode uses the standard minibuffer completion facilities
for entering tags.  However, it also implements another, quicker, tag
selection method called @emph{fast tag selection}.  This allows you to
select and deselect tags with just a single key press.  For this to
work well you should assign unique letters to most of your commonly
used tags.  You can do this globally by configuring the variable
@code{org-tag-alist} in your Emacs init file.  For example, you may find
the need to tag many items in different files with @samp{@@home}.  In this
case you can set something like:

@lisp
(setq org-tag-alist '(("@@work" . ?w) ("@@home" . ?h) ("laptop" . ?l)))
@end lisp

If the tag is only relevant to the file you are working on, then you
can instead set the @samp{TAGS} keyword as:

@example
#+TAGS: @@work(w)  @@home(h)  @@tennisclub(t)  laptop(l)  pc(p)
@end example


The tags interface shows the available tags in a splash window.  If
you want to start a new line after a specific tag, insert @samp{\n} into
the tag list

@example
#+TAGS: @@work(w) @@home(h) @@tennisclub(t) \n laptop(l) pc(p)
@end example


@noindent
or write them in two lines:

@example
#+TAGS: @@work(w)  @@home(h)  @@tennisclub(t)
#+TAGS: laptop(l)  pc(p)
@end example

You can also group together tags that are mutually exclusive by using
braces, as in:

@example
#+TAGS: @{ @@work(w)  @@home(h)  @@tennisclub(t) @}  laptop(l)  pc(p)
@end example


@noindent
you indicate that at most one of @samp{@@work}, @samp{@@home}, and @samp{@@tennisclub}
should be selected.  Multiple such groups are allowed.

Do not forget to press @kbd{C-c C-c} with point in one of these
lines to activate any changes.

To set these mutually exclusive groups in the variable
@code{org-tags-alist}, you must use the dummy tags @code{:startgroup} and
@code{:endgroup} instead of the braces.  Similarly, you can use @code{:newline}
to indicate a line break.  The previous example would be set globally
by the following configuration:

@lisp
(setq org-tag-alist '((:startgroup . nil)
                      ("@@work" . ?w) ("@@home" . ?h)
                      ("@@tennisclub" . ?t)
                      (:endgroup . nil)
                      ("laptop" . ?l) ("pc" . ?p)))
@end lisp

If at least one tag has a selection key then pressing @kbd{C-c C-c} automatically presents you with a special interface, listing
inherited tags, the tags of the current headline, and a list of all
valid tags with corresponding keys@footnote{Keys are automatically assigned to tags that have no
configured keys.}.

Pressing keys assigned to tags adds or removes them from the list of
tags in the current line.  Selecting a tag in a group of mutually
exclusive tags turns off any other tag from that group.

In this interface, you can also use the following special keys:

@table @asis
@item @kbd{@key{TAB}}
@kindex TAB
Enter a tag in the minibuffer, even if the tag is not in the
predefined list.  You can complete on all tags present in the
buffer.  You can also add several tags: just separate them with
a comma.

@item @kbd{@key{SPC}}
@kindex SPC
Clear all tags for this line.

@item @kbd{@key{RET}}
@kindex RET
Accept the modified set.

@item @kbd{C-g}
@kindex C-g
Abort without installing changes.

@item @kbd{q}
@kindex q
If @kbd{q} is not assigned to a tag, it aborts like
@kbd{C-g}.

@item @kbd{!}
@kindex !
Turn off groups of mutually exclusive tags.  Use this to (as an
exception) assign several tags from such a group.

@item @kbd{C-c}
@kindex C-c C-c
Toggle auto-exit after the next change (see below).  If you are
using expert mode, the first @kbd{C-c} displays the selection
window.
@end table

This method lets you assign tags to a headline with very few keys.
With the above setup, you could clear the current tags and set
@samp{@@home}, @samp{laptop} and @samp{pc} tags with just the following keys:
@kbd{C-c C-c @key{SPC} h l p @key{RET}}.  Switching from @samp{@@home} to @samp{@@work}
would be done with @kbd{C-c C-c w @key{RET}} or alternatively with
@kbd{C-c C-c C-c w}.  Adding the non-predefined tag @samp{sarah} could
be done with @kbd{C-c C-c @key{TAB} s a r a h @key{RET}}.

@vindex org-fast-tag-selection-single-key
If you find that most of the time you need only a single key press to
modify your list of tags, set the variable
@code{org-fast-tag-selection-single-key}.  Then you no longer have to press
@kbd{@key{RET}} to exit fast tag selection---it exits after the first
change.  If you then occasionally need more keys, press @kbd{C-c}
to turn off auto-exit for the current tag selection process (in
effect: start selection with @kbd{C-c C-c C-c} instead of
@kbd{C-c C-c}).  If you set the variable to the value @code{expert},
the special window is not even shown for single-key tag selection, it
comes up only when you press an extra @kbd{C-c}.

@node Tag Hierarchy
@section Tag Hierarchy

@cindex group tags
@cindex tags, groups
@cindex tags hierarchy

Tags can be defined in hierarchies.  A tag can be defined as a @emph{group
tag} for a set of other tags.  The group tag can be seen as the
``broader term'' for its set of tags.  Defining multiple group tags and
nesting them creates a tag hierarchy.

One use-case is to create a taxonomy of terms (tags) that can be used
to classify nodes in a document or set of documents.

When you search for a group tag, it return matches for all members in
the group and its subgroups.  In an agenda view, filtering by a group
tag displays or hide headlines tagged with at least one of the members
of the group or any of its subgroups.  This makes tag searches and
filters even more flexible.

You can set group tags by using brackets and inserting a colon between
the group tag and its related tags---beware that all whitespaces are
mandatory so that Org can parse this line correctly:

@example
#+TAGS: [ GTD : Control Persp ]
@end example


In this example, @samp{GTD} is the group tag and it is related to two other
tags: @samp{Control}, @samp{Persp}.  Defining @samp{Control} and @samp{Persp} as group
tags creates a hierarchy of tags:

@example
#+TAGS: [ Control : Context Task ]
#+TAGS: [ Persp : Vision Goal AOF Project ]
@end example

That can conceptually be seen as a hierarchy of tags:

@itemize
@item
@samp{GTD}
@itemize
@item
@samp{Persp}
@itemize
@item
@samp{Vision}
@item
@samp{Goal}
@item
@samp{AOF}
@item
@samp{Project}
@end itemize
@item
@samp{Control}
@itemize
@item
@samp{Context}
@item
@samp{Task}
@end itemize
@end itemize
@end itemize

You can use the @code{:startgrouptag}, @code{:grouptags} and @code{:endgrouptag}
keyword directly when setting @code{org-tag-alist} directly:

@lisp
(setq org-tag-alist '((:startgrouptag)
                      ("GTD")
                      (:grouptags)
                      ("Control")
                      ("Persp")
                      (:endgrouptag)
                      (:startgrouptag)
                      ("Control")
                      (:grouptags)
                      ("Context")
                      ("Task")
                      (:endgrouptag)))
@end lisp

The tags in a group can be mutually exclusive if using the same group
syntax as is used for grouping mutually exclusive tags together; using
curly brackets.

@example
#+TAGS: @{ Context : @@Home @@Work @@Call @}
@end example


When setting @code{org-tag-alist} you can use @code{:startgroup} and @code{:endgroup}
instead of @code{:startgrouptag} and @code{:endgrouptag} to make the tags
mutually exclusive.

Furthermore, the members of a group tag can also be regular
expressions, creating the possibility of a more dynamic and rule-based
tag structure.  The regular expressions in the group must be specified
within curly brackets.  Here is an expanded example:

@example
#+TAGS: [ Vision : @{V@@.+@} ]
#+TAGS: [ Goal : @{G@@.+@} ]
#+TAGS: [ AOF : @{AOF@@.+@} ]
#+TAGS: [ Project : @{P@@.+@} ]
@end example

Searching for the tag @samp{Project} now lists all tags also including
regular expression matches for @samp{P@@.+}, and similarly for tag searches
on @samp{Vision}, @samp{Goal} and @samp{AOF}.  For example, this would work well for
a project tagged with a common project-identifier, e.g.,
@samp{P@@2014_OrgTags}.

@kindex C-c C-x q
@findex org-toggle-tags-groups
@vindex org-group-tags
If you want to ignore group tags temporarily, toggle group tags
support with @code{org-toggle-tags-groups}, bound to @kbd{C-c C-x q}.
If you want to disable tag groups completely, set @code{org-group-tags} to
@code{nil}.

@node Tag Searches
@section Tag Searches

@cindex tag searches
@cindex searching for tags

Once a system of tags has been set up, it can be used to collect
related information into special lists.

@table @asis
@item @kbd{C-c / m} or @kbd{C-c \} (@code{org-match-sparse-tree})
@kindex C-c / m
@kindex C-c \
@findex org-match-sparse-tree
Create a sparse tree with all headlines matching a tags search.
With a @kbd{C-u} prefix argument, ignore headlines that are not
a TODO line.

@item @kbd{M-x org-agenda m} (@code{org-tags-view})
@kindex m @r{(Agenda dispatcher)}
@findex org-tags-view
Create a global list of tag matches from all agenda files.  See
@ref{Matching tags and properties}.

@item @kbd{M-x org-agenda M} (@code{org-tags-view})
@kindex M @r{(Agenda dispatcher)}
@vindex org-tags-match-list-sublevels
Create a global list of tag matches from all agenda files, but check
only TODO items and force checking subitems (see the option
@code{org-tags-match-list-sublevels}).
@end table

These commands all prompt for a match string which allows basic
Boolean logic like @samp{+boss+urgent-project1}, to find entries with tags
@samp{boss} and @samp{urgent}, but not @samp{project1}, or @samp{Kathy|Sally} to find
entries which are tagged, like @samp{Kathy} or @samp{Sally}.  The full syntax of
the search string is rich and allows also matching against TODO
keywords, entry levels and properties.  For a complete description
with many examples, see @ref{Matching tags and properties}.

@node Properties and Columns
@chapter Properties and Columns

@cindex properties

A property is a key-value pair associated with an entry.  Properties
can be set so they are associated with a single entry, with every
entry in a tree, or with every entry in an Org file.

There are two main applications for properties in Org mode.  First,
properties are like tags, but with a value.  Imagine maintaining
a file where you document bugs and plan releases for a piece of
software.  Instead of using tags like @samp{release_1}, @samp{release_2}, you
can use a property, say @samp{Release}, that in different subtrees has
different values, such as @samp{1.0} or @samp{2.0}.  Second, you can use
properties to implement (very basic) database capabilities in an Org
buffer.  Imagine keeping track of your music CDs, where properties
could be things such as the album, artist, date of release, number of
tracks, and so on.

Properties can be conveniently edited and viewed in column view (see
@ref{Column View}).

@menu
* Property Syntax::              How properties are spelled out.
* Special Properties::           Access to other Org mode features.
* Property Searches::            Matching property values.
* Property Inheritance::         Passing values down a tree.
* Column View::                  Tabular viewing and editing.
@end menu

@node Property Syntax
@section Property Syntax

@cindex property syntax
@cindex drawer, for properties

Properties are key--value pairs.  When they are associated with
a single entry or with a tree they need to be inserted into a special
drawer (see @ref{Drawers}) with the name @samp{PROPERTIES}, which has to be
located right below a headline, and its planning line (see @ref{Deadlines and Scheduling}) when applicable.  Each property is specified on
a single line, with the key---surrounded by colons---first, and the
value after it.  Keys are case-insensitive.  Here is an example:

@example
* CD collection
** Classic
*** Goldberg Variations
    :PROPERTIES:
    :Title:     Goldberg Variations
    :Composer:  J.S. Bach
    :Artist:    Glenn Gould
    :Publisher: Deutsche Grammophon
    :NDisks:    1
    :END:
@end example

Depending on the value of @code{org-use-property-inheritance}, a property
set this way is associated either with a single entry, or with the
sub-tree defined by the entry, see @ref{Property Inheritance}.

You may define the allowed values for a particular property @samp{Xyz} by
setting a property @samp{Xyz_ALL}.  This special property is @emph{inherited},
so if you set it in a level 1 entry, it applies to the entire tree.
When allowed values are defined, setting the corresponding property
becomes easier and is less prone to typing errors.  For the example
with the CD collection, we can pre-define publishers and the number of
disks in a box like this:

@example
* CD collection
  :PROPERTIES:
  :NDisks_ALL:  1 2 3 4
  :Publisher_ALL: "Deutsche Grammophon" Philips EMI
  :END:
@end example

If you want to set properties that can be inherited by any entry in
a file, use a line like:

@cindex @samp{_ALL} suffix, in properties
@cindex @samp{PROPERTY}, keyword
@example
#+PROPERTY: NDisks_ALL 1 2 3 4
@end example


@cindex @samp{+} suffix, in properties
If you want to add to the value of an existing property, append a @samp{+}
to the property name.  The following results in the property @samp{var}
having the value @samp{foo=1 bar=2}.

@example
#+PROPERTY: var  foo=1
#+PROPERTY: var+ bar=2
@end example

It is also possible to add to the values of inherited properties.  The
following results in the @samp{Genres} property having the value @samp{Classic
Baroque} under the @samp{Goldberg Variations} subtree.

@example
* CD collection
** Classic
    :PROPERTIES:
    :Genres: Classic
    :END:
*** Goldberg Variations
    :PROPERTIES:
    :Title:     Goldberg Variations
    :Composer:  J.S. Bach
    :Artist:    Glenn Gould
    :Publisher: Deutsche Grammophon
    :NDisks:    1
    :Genres+:   Baroque
    :END:
@end example

Note that a property can only have one entry per drawer.

@vindex org-global-properties
Property values set with the global variable @code{org-global-properties}
can be inherited by all entries in all Org files.

The following commands help to work with properties:

@table @asis
@item @kbd{M-@key{TAB}} (@code{pcomplete})
@kindex M-TAB
@findex pcomplete
After an initial colon in a line, complete property keys.  All keys
used in the current file are offered as possible completions.

@item @kbd{C-c C-x p} (@code{org-set-property})
@kindex C-c C-x p
@findex org-set-property
Set a property.  This prompts for a property name and a value.  If
necessary, the property drawer is created as well.

@item @kbd{C-u M-x org-insert-drawer}
@findex org-insert-drawer
Insert a property drawer into the current entry.  The drawer is
inserted early in the entry, but after the lines with planning
information like deadlines.

@item @kbd{C-c C-c} (@code{org-property-action})
@kindex C-c C-c
@findex org-property-action
With point in a property drawer, this executes property commands.

@item @kbd{C-c C-c s} (@code{org-set-property})
@kindex C-c C-c s
@findex org-set-property
Set a property in the current entry.  Both the property and the
value can be inserted using completion.

@item @kbd{S-@key{RIGHT}} (@code{org-property-next-allowed-values})
@itemx @kbd{S-@key{LEFT}} (@code{org-property-previous-allowed-value})
@kindex S-RIGHT
@kindex S-LEFT
Switch property at point to the next/previous allowed value.

@item @kbd{C-c C-c d} (@code{org-delete-property})
@kindex C-c C-c d
@findex org-delete-property
Remove a property from the current entry.

@item @kbd{C-c C-c D} (@code{org-delete-property-globally})
@kindex C-c C-c D
@findex org-delete-property-globally
Globally remove a property, from all entries in the current file.

@item @kbd{C-c C-c c} (@code{org-compute-property-at-point})
@kindex C-c C-c c
@findex org-compute-property-at-point
Compute the property at point, using the operator and scope from the
nearest column format definition.
@end table

@node Special Properties
@section Special Properties

@cindex properties, special

Special properties provide an alternative access method to Org mode
features, like the TODO state or the priority of an entry, discussed
in the previous chapters.  This interface exists so that you can
include these states in a column view (see @ref{Column View}), or to use
them in queries.  The following property names are special and should
not be used as keys in the properties drawer:

@cindex @samp{ALLTAGS}, special property
@cindex @samp{BLOCKED}, special property
@cindex @samp{CLOCKSUM}, special property
@cindex @samp{CLOCKSUM_T}, special property
@cindex @samp{CLOSED}, special property
@cindex @samp{DEADLINE}, special property
@cindex @samp{FILE}, special property
@cindex @samp{ITEM}, special property
@cindex @samp{PRIORITY}, special property
@cindex @samp{SCHEDULED}, special property
@cindex @samp{TAGS}, special property
@cindex @samp{TIMESTAMP}, special property
@cindex @samp{TIMESTAMP_IA}, special property
@cindex @samp{TODO}, special property
@multitable {aaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{ALLTAGS}
@tab All tags, including inherited ones.
@item @samp{BLOCKED}
@tab @code{t} if task is currently blocked by children or siblings.
@item @samp{CATEGORY}
@tab The category of an entry.
@item @samp{CLOCKSUM}
@tab The sum of CLOCK intervals in the subtree.  @code{org-clock-sum}
@item 
@tab must be run first to compute the values in the current buffer.
@item @samp{CLOCKSUM_T}
@tab The sum of CLOCK intervals in the subtree for today.
@item 
@tab @code{org-clock-sum-today} must be run first to compute the
@item 
@tab values in the current buffer.
@item @samp{CLOSED}
@tab When was this entry closed?
@item @samp{DEADLINE}
@tab The deadline time string, without the angular brackets.
@item @samp{FILE}
@tab The filename the entry is located in.
@item @samp{ITEM}
@tab The headline of the entry.
@item @samp{PRIORITY}
@tab The priority of the entry, a string with a single letter.
@item @samp{SCHEDULED}
@tab The scheduling timestamp, without the angular brackets.
@item @samp{TAGS}
@tab The tags defined directly in the headline.
@item @samp{TIMESTAMP}
@tab The first keyword-less timestamp in the entry.
@item @samp{TIMESTAMP_IA}
@tab The first inactive timestamp in the entry.
@item @samp{TODO}
@tab The TODO keyword of the entry.
@end multitable

@node Property Searches
@section Property Searches

@cindex properties, searching
@cindex searching, of properties

To create sparse trees and special lists with selection based on
properties, the same commands are used as for tag searches (see @ref{Tag Searches}).

@table @asis
@item @kbd{C-c / m} or @kbd{C-c \} (@code{org-match-sparse-tree})
@kindex C-c / m
@kindex C-c \
@findex org-match-sparse-tree
Create a sparse tree with all matching entries.  With
a @kbd{C-u} prefix argument, ignore headlines that are not
a TODO line.

@item @kbd{M-x org-agenda m}, @code{org-tags-view}
@kindex m @r{(Agenda dispatcher)}
@findex org-tags-view
Create a global list of tag/property matches from all agenda files.

@item @kbd{M-x org-agenda M} (@code{org-tags-view})
@kindex M @r{(Agenda dispatcher)}
@vindex org-tags-match-list-sublevels
Create a global list of tag matches from all agenda files, but check
only TODO items and force checking of subitems (see the option
@code{org-tags-match-list-sublevels}).
@end table

The syntax for the search string is described in @ref{Matching tags and properties}.

There is also a special command for creating sparse trees based on a
single property:

@table @asis
@item @kbd{C-c / p}
@kindex C-c / p
Create a sparse tree based on the value of a property.  This first
prompts for the name of a property, and then for a value.  A sparse
tree is created with all entries that define this property with the
given value.  If you enclose the value in curly braces, it is
interpreted as a regular expression and matched against the property
values.
@end table

@node Property Inheritance
@section Property Inheritance

@cindex properties, inheritance
@cindex inheritance, of properties

@vindex org-use-property-inheritance
The outline structure of Org documents lends itself to an inheritance
model of properties: if the parent in a tree has a certain property,
the children can inherit this property.  Org mode does not turn this
on by default, because it can slow down property searches
significantly and is often not needed.  However, if you find
inheritance useful, you can turn it on by setting the variable
@code{org-use-property-inheritance}.  It may be set to @code{t} to make all
properties inherited from the parent, to a list of properties that
should be inherited, or to a regular expression that matches inherited
properties.  If a property has the value @code{nil}, this is interpreted as
an explicit un-define of the property, so that inheritance search
stops at this value and returns @code{nil}.

Org mode has a few properties for which inheritance is hard-coded, at
least for the special applications for which they are used:

@table @asis
@item @code{COLUMNS}
@cindex @samp{COLUMNS}, property
The @samp{COLUMNS} property defines the format of column view (see
@ref{Column View}).  It is inherited in the sense that the level where
a @samp{COLUMNS} property is defined is used as the starting point for
a column view table, independently of the location in the subtree
from where columns view is turned on.

@item @code{CATEGORY}
@cindex @samp{CATEGORY}, property
For agenda view, a category set through a @samp{CATEGORY} property
applies to the entire subtree.

@item @code{ARCHIVE}
@cindex @samp{ARCHIVE}, property
For archiving, the @samp{ARCHIVE} property may define the archive
location for the entire subtree (see @ref{Moving subtrees}).

@item @code{LOGGING}
@cindex @samp{LOGGING}, property
The @samp{LOGGING} property may define logging settings for an entry or
a subtree (see @ref{Tracking TODO state changes}).
@end table

@node Column View
@section Column View

A great way to view and edit properties in an outline tree is @emph{column
view}.  In column view, each outline node is turned into a table row.
Columns in this table provide access to properties of the entries.
Org mode implements columns by overlaying a tabular structure over the
headline of each item.  While the headlines have been turned into
a table row, you can still change the visibility of the outline tree.
For example, you get a compact table by switching to ``contents''
view---@kbd{S-@key{TAB}} @kbd{S-@key{TAB}}, or simply @kbd{c}
while column view is active---but you can still open, read, and edit
the entry below each headline.  Or, you can switch to column view
after executing a sparse tree command and in this way get a table only
for the selected items.  Column view also works in agenda buffers (see
@ref{Agenda Views}) where queries have collected selected items, possibly
from a number of files.

@menu
* Defining columns::             The COLUMNS format property.
* Using column view::            How to create and use column view.
* Capturing column view::        A dynamic block for column view.
@end menu

@node Defining columns
@subsection Defining columns

@cindex column view, for properties
@cindex properties, column view

Setting up a column view first requires defining the columns.  This is
done by defining a column format line.

@menu
* Scope of column definitions::  Where defined, where valid?
* Column attributes::            Appearance and content of a column.
@end menu

@node Scope of column definitions
@subsubsection Scope of column definitions

To define a column format for an entire file, use a line like:

@cindex @samp{COLUMNS}, keyword
@example
#+COLUMNS: %25ITEM %TAGS %PRIORITY %TODO
@end example


To specify a format that only applies to a specific tree, add
a @samp{COLUMNS} property to the top node of that tree, for example:

@example
** Top node for columns view
   :PROPERTIES:
   :COLUMNS: %25ITEM %TAGS %PRIORITY %TODO
   :END:
@end example

If a @samp{COLUMNS} property is present in an entry, it defines columns for
the entry itself, and for the entire subtree below it.  Since the
column definition is part of the hierarchical structure of the
document, you can define columns on level 1 that are general enough
for all sublevels, and more specific columns further down, when you
edit a deeper part of the tree.

@node Column attributes
@subsubsection Column attributes

A column definition sets the attributes of a column.  The general
definition looks like this:

@example
%[WIDTH]PROPERTY[(TITLE)][@{SUMMARY-TYPE@}]
@end example


@noindent
Except for the percent sign and the property name, all items are
optional.  The individual parts have the following meaning:

@table @asis
@item @var{WIDTH}
An integer specifying the width of the column in characters.  If
omitted, the width is determined automatically.

@item @var{PROPERTY}
The property that should be edited in this column.  Special
properties representing meta data are allowed here as well (see
@ref{Special Properties}).

@item @var{TITLE}
The header text for the column.  If omitted, the property name is
used.

@item @var{SUMMARY-TYPE}
The summary type.  If specified, the column values for parent nodes
are computed from the children@footnote{If more than one summary type applies to the same property,
the parent values are computed according to the first of them.}.

Supported summary types are:

@multitable {aaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{+}
@tab Sum numbers in this column.
@item @samp{+;%.1f}
@tab Like @samp{+}, but format result with @samp{%.1f}.
@item @samp{$}
@tab Currency, short for @samp{+;%.2f}.
@item @samp{min}
@tab Smallest number in column.
@item @samp{max}
@tab Largest number.
@item @samp{mean}
@tab Arithmetic mean of numbers.
@item @samp{X}
@tab Checkbox status, @samp{[X]} if all children are @samp{[X]}.
@item @samp{X/}
@tab Checkbox status, @samp{[n/m]}.
@item @samp{X%}
@tab Checkbox status, @samp{[n%]}.
@item @samp{:}
@tab Sum times, HH:MM, plain numbers are minutes.
@item @samp{:min}
@tab Smallest time value in column.
@item @samp{:max}
@tab Largest time value.
@item @samp{:mean}
@tab Arithmetic mean of time values.
@item @samp{@@min}
@tab Minimum age@footnote{An age can be defined as a duration, using units defined in
@code{org-duration-units}, e.g., @samp{3d 1h}.  If any value in the column is as
such, the summary is also expressed as a duration.} (in days/hours/mins/seconds).
@item @samp{@@max}
@tab Maximum age (in days/hours/mins/seconds).
@item @samp{@@mean}
@tab Arithmetic mean of ages (in days/hours/mins/seconds).
@item @samp{est+}
@tab Add low-high estimates.
@end multitable

@vindex org-columns-summary-types
You can also define custom summary types by setting
@code{org-columns-summary-types}.
@end table

The @samp{est+} summary type requires further explanation.  It is used for
combining estimates, expressed as low-high ranges.  For example,
instead of estimating a particular task will take 5 days, you might
estimate it as 5--6 days if you're fairly confident you know how much
work is required, or 1--10 days if you do not really know what needs
to be done.  Both ranges average at 5.5 days, but the first represents
a more predictable delivery.

When combining a set of such estimates, simply adding the lows and
highs produces an unrealistically wide result.  Instead, @samp{est+} adds
the statistical mean and variance of the subtasks, generating a final
estimate from the sum.  For example, suppose you had ten tasks, each
of which was estimated at 0.5 to 2 days of work.  Straight addition
produces an estimate of 5 to 20 days, representing what to expect if
everything goes either extremely well or extremely poorly.  In
contrast, @samp{est+} estimates the full job more realistically, at 10--15
days.

Here is an example for a complete columns definition, along with
allowed values@footnote{Please note that the @samp{COLUMNS} definition must be on a single
line; it is wrapped here only because of formatting constraints.}.

@example
:COLUMNS:  %25ITEM %9Approved(Approved?)@{X@} %Owner %11Status \
                   %10Time_Estimate@{:@} %CLOCKSUM %CLOCKSUM_T
:Owner_ALL:    Tammy Mark Karl Lisa Don
:Status_ALL:   "In progress" "Not started yet" "Finished" ""
:Approved_ALL: "[ ]" "[X]"
@end example

@noindent
The first column, @samp{%25ITEM}, means the first 25 characters of the item
itself, i.e., of the headline.  You probably always should start the
column definition with the @samp{ITEM} specifier.  The other specifiers
create columns @samp{Owner} with a list of names as allowed values, for
@samp{Status} with four different possible values, and for a checkbox field
@samp{Approved}.  When no width is given after the @samp{%} character, the
column is exactly as wide as it needs to be in order to fully display
all values.  The @samp{Approved} column does have a modified title
(@samp{Approved?}, with a question mark).  Summaries are created for the
@samp{Time_Estimate} column by adding time duration expressions like HH:MM,
and for the @samp{Approved} column, by providing an @samp{[X]} status if all
children have been checked.  The @samp{CLOCKSUM} and @samp{CLOCKSUM_T} columns
are special, they lists the sums of CLOCK intervals in the subtree,
either for all clocks or just for today.

@node Using column view
@subsection Using column view



@anchor{Turning column view on or off}
@subsubheading Turning column view on or off

@table @asis
@item @kbd{C-c C-x C-c} (@code{org-columns})
@kindex C-c C-x C-c
@vindex org-columns
@vindex org-columns-default-format
Turn on column view.  If point is before the first headline in the
file, column view is turned on for the entire file, using the
@samp{#+COLUMNS} definition.  If point is somewhere inside the outline,
this command searches the hierarchy, up from point, for a @samp{COLUMNS}
property that defines a format.  When one is found, the column view
table is established for the tree starting at the entry that
contains the @samp{COLUMNS} property.  If no such property is found, the
format is taken from the @samp{#+COLUMNS} line or from the variable
@code{org-columns-default-format}, and column view is established for the
current entry and its subtree.

@item @kbd{r} or @kbd{g} (@code{org-columns-redo})
@kindex r
@kindex g
@findex org-columns-redo
Recreate the column view, to include recent changes made in the
buffer.

@item @kbd{q} (@code{org-columns-quit})
@kindex q
@findex org-columns-quit
Exit column view.
@end table

@anchor{Editing values}
@subsubheading Editing values

@table @asis
@item @kbd{@key{LEFT}}, @kbd{@key{RIGHT}}, @kbd{@key{UP}}, @kbd{@key{DOWN}}
Move through the column view from field to field.

@item @kbd{1..9,0}
@kindex 1..9,0
Directly select the Nth allowed value, @kbd{0} selects the
10th value.

@item @kbd{n} or @kbd{S-@key{RIGHT}} (@code{org-columns-next-allowed-value})
@itemx @kbd{p} or @kbd{S-@key{LEFT}} (@code{org-columns-previous-allowed-value})
@kindex n
@kindex S-RIGHT
@kindex p
@kindex S-LEFT
@findex org-columns-next-allowed-value
@findex org-columns-previous-allowed-value
Switch to the next/previous allowed value of the field.  For this,
you have to have specified allowed values for a property.

@item @kbd{e} (@code{org-columns-edit-value})
@kindex e
@findex org-columns-edit-value
Edit the property at point.  For the special properties, this
invokes the same interface that you normally use to change that
property.  For example, the tag completion or fast selection
interface pops up when editing a @samp{TAGS} property.

@item @kbd{C-c C-c} (@code{org-columns-set-tags-or-toggle})
@kindex C-c C-c
@findex org-columns-set-tags-or-toggle
When there is a checkbox at point, toggle it.

@item @kbd{v} (@code{org-columns-show-value})
@kindex v
@findex org-columns-show-value
View the full value of this property.  This is useful if the width
of the column is smaller than that of the value.

@item @kbd{a} (@code{org-columns-edit-allowed})
@kindex a
@findex org-columns-edit-allowed
Edit the list of allowed values for this property.  If the list is
found in the hierarchy, the modified values is stored there.  If no
list is found, the new value is stored in the first entry that is
part of the current column view.
@end table

@anchor{Modifying column view on-the-fly}
@subsubheading Modifying column view on-the-fly

@table @asis
@item @kbd{<} (@code{org-columns-narrow})
@itemx @kbd{>} (@code{org-columns-widen})
@kindex <
@kindex >
@findex org-columns-narrow
@findex org-columns-widen
Make the column narrower/wider by one character.

@item @kbd{S-M-@key{RIGHT}} (@code{org-columns-new})
@kindex S-M-RIGHT
@findex org-columns-new
Insert a new column, to the left of the current column.

@item @kbd{S-M-@key{LEFT}} (@code{org-columns-delete})
@kindex S-M-LEFT
@findex org-columns-delete
Delete the current column.
@end table

@node Capturing column view
@subsection Capturing column view

Since column view is just an overlay over a buffer, it cannot be
exported or printed directly.  If you want to capture a column view,
use a @samp{columnview} dynamic block (see @ref{Dynamic Blocks}).  The frame of
this block looks like this:

@cindex @samp{BEGIN columnview}
@example
* The column view
#+BEGIN: columnview :hlines 1 :id "label"

#+END:
@end example

This dynamic block has the following parameters:

@table @asis
@item @samp{:id}
This is the most important parameter.  Column view is a feature that
is often localized to a certain (sub)tree, and the capture block
might be at a different location in the file.  To identify the tree
whose view to capture, you can use four values:

@table @asis
@item @samp{local}
Use the tree in which the capture block is located.

@item @samp{global}
Make a global view, including all headings in the file.

@item @samp{file:FILENAME}
Run column view at the top of the @var{FILENAME} file.

@item @samp{LABEL}
@cindex @samp{ID}, property
Call column view in the tree that has an @samp{ID} property with the
value @var{LABEL}.  You can use @kbd{M-x org-id-copy} to
create a globally unique ID for the current entry and copy it to
the kill-ring.
@end table

@item @samp{:hlines}
When @code{t}, insert an hline after every line.  When a number N, insert
an hline before each headline with level @code{<= N}.

@item @samp{:vlines}
When non-@code{nil}, force column groups to get vertical lines.

@item @samp{:maxlevel}
When set to a number, do not capture entries below this level.

@item @samp{:skip-empty-rows}
When non-@code{nil}, skip rows where the only non-empty specifier of
the column view is @samp{ITEM}.

@item @samp{:exclude-tags}
List of tags to exclude from column view table: entries with these
tags will be excluded from the column view.

@item @samp{:indent}
When non-@code{nil}, indent each @samp{ITEM} field according to its level.

@item @samp{:format}
Specify a column attribute (see @ref{Column attributes}) for the dynamic
block.
@end table

The following commands insert or update the dynamic block:

@table @asis
@item @kbd{C-c C-x i} (@code{org-insert-columns-dblock})
@kindex C-c C-x i
@findex org-insert-columns-dblock
Insert a dynamic block capturing a column view.  Prompt for the
scope or ID of the view.

@item @kbd{C-c C-c} @kbd{C-c C-x C-u} (@code{org-dblock-update})
@kindex C-c C-c
@kindex C-c C-x C-u
@findex org-dblock-update
Update dynamic block at point.  point needs to be in the @samp{#+BEGIN}
line of the dynamic block.

@item @kbd{C-u C-c C-x C-u} (@code{org-update-all-dblocks})
@kindex C-u C-c C-x C-u
Update all dynamic blocks (see @ref{Dynamic Blocks}).  This is useful if
you have several clock table blocks, column-capturing blocks or
other dynamic blocks in a buffer.
@end table

You can add formulas to the column view table and you may add plotting
instructions in front of the table---these survive an update of the
block.  If there is a @samp{TBLFM} keyword after the table, the table is
recalculated automatically after an update.

An alternative way to capture and process property values into a table
is provided by Eric Schulte's @samp{org-collector.el}, which is
a contributed package@footnote{Contributed packages are not part of Emacs, but are
distributed with the main distribution of Org---visit
@uref{https://orgmode.org}.}.  It provides a general API to collect
properties from entries in a certain scope, and arbitrary Lisp
expressions to process these values before inserting them into a table
or a dynamic block.

@node Dates and Times
@chapter Dates and Times

@cindex dates
@cindex times
@cindex timestamp
@cindex date stamp

To assist project planning, TODO items can be labeled with a date
and/or a time.  The specially formatted string carrying the date and
time information is called a @emph{timestamp} in Org mode.  This may be
a little confusing because timestamp is often used as indicating when
something was created or last changed.  However, in Org mode this term
is used in a much wider sense.

@menu
* Timestamps::                   Assigning a time to a tree entry.
* Creating Timestamps::          Commands to insert timestamps.
* Deadlines and Scheduling::     Planning your work.
* Clocking Work Time::           Tracking how long you spend on a task.
* Effort Estimates::             Planning work effort in advance.
* Timers::                       Notes with a running timer.
@end menu

@node Timestamps
@section Timestamps

@cindex timestamps
@cindex ranges, time
@cindex date stamps
@cindex deadlines
@cindex scheduling

A timestamp is a specification of a date (possibly with a time or
a range of times) in a special format, either @samp{<2003-09-16 Tue>} or
@samp{<2003-09-16 Tue 09:39>} or @samp{<2003-09-16 Tue 12:00-12:30>}@footnote{The Org date format is inspired by the standard ISO 8601
date/time format.  To use an alternative format, see @ref{Custom time format}.  The day name is optional when you type the date yourself.
However, any date inserted or modified by Org adds that day name, for
reading convenience.}.
A timestamp can appear anywhere in the headline or body of an Org tree
entry.  Its presence causes entries to be shown on specific dates in
the agenda (see @ref{Weekly/daily agenda}).  We distinguish:

@table @asis
@item Plain timestamp; Event; Appointment
@cindex timestamp
@cindex appointment
A simple timestamp just assigns a date/time to an item.  This is
just like writing down an appointment or event in a paper agenda.
In the agenda display, the headline of an entry associated with
a plain timestamp is shown exactly on that date.

@example
* Meet Peter at the movies
  <2006-11-01 Wed 19:15>
* Discussion on climate change
  <2006-11-02 Thu 20:00-22:00>
@end example

@item Timestamp with repeater interval
@cindex timestamp, with repeater interval
A timestamp may contain a @emph{repeater interval}, indicating that it
applies not only on the given date, but again and again after
a certain interval of N days (d), weeks (w), months (m), or years
(y).  The following shows up in the agenda every Wednesday:

@example
* Pick up Sam at school
  <2007-05-16 Wed 12:30 +1w>
@end example

@item Diary-style expression entries
@cindex diary style timestamps
@cindex sexp timestamps
For more complex date specifications, Org mode supports using the
special expression diary entries implemented in the Emacs Calendar
package@footnote{When working with the standard diary expression functions, you
need to be very careful with the order of the arguments.  That order
depends evilly on the variable @code{calendar-date-style}.  For example, to
specify a date December 12, 2005, the call might look like
@samp{(diary-date 12 1 2005)} or @samp{(diary-date 1 12 2005)} or @samp{(diary-date
2005 12 1)}, depending on the settings.  This has been the source of
much confusion.  Org mode users can resort to special versions of
these functions like @code{org-date} or @code{org-anniversary}.  These work just
like the corresponding @code{diary-} functions, but with stable ISO order
of arguments (year, month, day) wherever applicable, independent of
the value of @code{calendar-date-style}.}.  For example, with optional time:

@example
* 22:00-23:00 The nerd meeting on every 2nd Thursday of the month
  <%%(diary-float t 4 2)>
@end example

@item Time/Date range
@cindex timerange
@cindex date range
Two timestamps connected by @samp{--} denote a range.  The headline is
shown on the first and last day of the range, and on any dates that
are displayed and fall in the range.  Here is an example:

@example
** Meeting in Amsterdam
   <2004-08-23 Mon>--<2004-08-26 Thu>
@end example

@item Inactive timestamp
@cindex timestamp, inactive
@cindex inactive timestamp
Just like a plain timestamp, but with square brackets instead of
angular ones.  These timestamps are inactive in the sense that they
do @emph{not} trigger an entry to show up in the agenda.

@example
* Gillian comes late for the fifth time
  [2006-11-01 Wed]
@end example
@end table

@node Creating Timestamps
@section Creating Timestamps

For Org mode to recognize timestamps, they need to be in the specific
format.  All commands listed below produce timestamps in the correct
format.

@table @asis
@item @kbd{C-c .} (@code{org-time-stamp})
@kindex C-c .
@findex org-time-stamp
Prompt for a date and insert a corresponding timestamp.  When point
is at an existing timestamp in the buffer, the command is used to
modify this timestamp instead of inserting a new one.  When this
command is used twice in succession, a time range is inserted.

@kindex C-u C-c .
@vindex org-time-stamp-rounding-minutes
When called with a prefix argument, use the alternative format which
contains date and time.  The default time can be rounded to
multiples of 5 minutes.  See the option
@code{org-time-stamp-rounding-minutes}.

@kindex C-u C-u C-c .
With two prefix arguments, insert an active timestamp with the
current time without prompting.

@item @kbd{C-c !} (@code{org-time-stamp-inactive})
@kindex C-c !
@kindex C-u C-c !
@kindex C-u C-u C-c !
@findex org-time-stamp-inactive
Like @kbd{C-c .}, but insert an inactive timestamp that does
not cause an agenda entry.

@item @kbd{C-c C-c}
@kindex C-c C-c
Normalize timestamp, insert or fix day name if missing or wrong.

@item @kbd{C-c <} (@code{org-date-from-calendar})
@kindex C-c <
@findex org-date-from-calendar
Insert a timestamp corresponding to point date in the calendar.

@item @kbd{C-c >} (@code{org-goto-calendar})
@kindex C-c >
@findex org-goto-calendar
Access the Emacs calendar for the current date.  If there is
a timestamp in the current line, go to the corresponding date
instead.

@item @kbd{C-c C-o} (@code{org-open-at-point})
@kindex C-c C-o
@findex org-open-at-point
Access the agenda for the date given by the timestamp or -range at
point (see @ref{Weekly/daily agenda}).

@item @kbd{S-@key{LEFT}} (@code{org-timestamp-down-day})
@itemx @kbd{S-@key{RIGHT}} (@code{org-timestamp-up-day})
@kindex S-LEFT
@kindex S-RIGHT
@findex org-timestamp-down-day
@findex org-timestamp-up-day
Change date at point by one day.  These key bindings conflict with
shift-selection and related modes (see @ref{Conflicts}).

@item @kbd{S-@key{UP}} (@code{org-timestamp-up})
@itemx @kbd{S-@key{DOWN}} (@code{org-timestamp-down})
@kindex S-UP
@kindex S-DOWN
On the beginning or enclosing bracket of a timestamp, change its
type.  Within a timestamp, change the item under point.  Point can
be on a year, month, day, hour or minute.  When the timestamp
contains a time range like @samp{15:30-16:30}, modifying the first time
also shifts the second, shifting the time block with constant
length.  To change the length, modify the second time.  Note that if
point is in a headline and not at a timestamp, these same keys
modify the priority of an item (see @ref{Priorities}).  The key bindings
also conflict with shift-selection and related modes (see @ref{Conflicts}).

@item @kbd{C-c C-y} (@code{org-evaluate-time-range})
@kindex C-c C-y
@findex org-evaluate-time-range
@cindex evaluate time range
Evaluate a time range by computing the difference between start and
end.  With a prefix argument, insert result after the time range (in
a table: into the following column).
@end table

@menu
* The date/time prompt::         How Org mode helps you enter dates and times.
* Custom time format::           Making dates look different.
@end menu

@node The date/time prompt
@subsection The date/time prompt

@cindex date, reading in minibuffer
@cindex time, reading in minibuffer

@vindex org-read-date-prefer-future
When Org mode prompts for a date/time, the default is shown in default
date/time format, and the prompt therefore seems to ask for a specific
format.  But it in fact accepts date/time information in a variety of
formats.  Generally, the information should start at the beginning of
the string.  Org mode finds whatever information is in there and
derives anything you have not specified from the @emph{default date and
time}.  The default is usually the current date and time, but when
modifying an existing timestamp, or when entering the second stamp of
a range, it is taken from the stamp in the buffer.  When filling in
information, Org mode assumes that most of the time you want to enter
a date in the future: if you omit the month/year and the given
day/month is @emph{before} today, it assumes that you mean a future
date@footnote{See the variable @code{org-read-date-prefer-future}.  You may set
that variable to the symbol @code{time} to even make a time before now
shift the date to tomorrow.}.  If the date has been automatically shifted into the
future, the time prompt shows this with @samp{(=>F)}.

For example, let's assume that today is @strong{June 13, 2006}.  Here is how
various inputs are interpreted, the items filled in by Org mode are in
@strong{bold}.

@multitable {aaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{3-2-5}
@tab @result{} 2003-02-05
@item @samp{2/5/3}
@tab @result{} 2003-02-05
@item @samp{14}
@tab @result{} @strong{2006}-@strong{06}-14
@item @samp{12}
@tab @result{} @strong{2006}-@strong{07}-12
@item @samp{2/5}
@tab @result{} @strong{2007}-02-05
@item @samp{Fri}
@tab @result{} nearest Friday (default date or later)
@item @samp{sep 15}
@tab @result{} @strong{2006}-09-15
@item @samp{feb 15}
@tab @result{} @strong{2007}-02-15
@item @samp{sep 12 9}
@tab @result{} 2009-09-12
@item @samp{12:45}
@tab @result{} @strong{2006}-@strong{06}-@strong{13} 12:45
@item @samp{22 sept 0:34}
@tab @result{} @strong{2006}-09-22 0:34
@item @samp{w4}
@tab @result{} ISO week for of the current year @strong{2006}
@item @samp{2012 w4 fri}
@tab @result{} Friday of ISO week 4 in 2012
@item @samp{2012-w04-5}
@tab @result{} Same as above
@end multitable

Furthermore you can specify a relative date by giving, as the @emph{first}
thing in the input: a plus/minus sign, a number and a letter---@samp{d},
@samp{w}, @samp{m} or @samp{y}---to indicate change in days, weeks, months, or
years.  With a single plus or minus, the date is always relative to
today.  With a double plus or minus, it is relative to the default
date.  If instead of a single letter, you use the abbreviation of day
name, the date is the Nth such day, e.g.:

@multitable {aaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{+0}
@tab @result{} today
@item @samp{.}
@tab @result{} today
@item @samp{+4d}
@tab @result{} four days from today
@item @samp{+4}
@tab @result{} same as +4d
@item @samp{+2w}
@tab @result{} two weeks from today
@item @samp{++5}
@tab @result{} five days from default date
@item @samp{+2tue}
@tab @result{} second Tuesday from now
@end multitable

@vindex parse-time-months
@vindex parse-time-weekdays
The function understands English month and weekday abbreviations.  If
you want to use un-abbreviated names and/or other languages, configure
the variables @code{parse-time-months} and @code{parse-time-weekdays}.

@vindex org-read-date-force-compatible-dates
Not all dates can be represented in a given Emacs implementation.  By
default Org mode forces dates into the compatibility range 1970--2037
which works on all Emacs implementations.  If you want to use dates
outside of this range, read the docstring of the variable
@code{org-read-date-force-compatible-dates}.

You can specify a time range by giving start and end times or by
giving a start time and a duration (in HH:MM format).  Use one or two
dash(es) as the separator in the former case and use @samp{+} as the
separator in the latter case, e.g.:

@multitable {aaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaa}
@item @samp{11am-1:15pm}
@tab @result{} 11:00-13:15
@item @samp{11am--1:15pm}
@tab @result{} same as above
@item @samp{11am+2:15}
@tab @result{} same as above
@end multitable

@cindex calendar, for selecting date
@vindex org-popup-calendar-for-date-prompt
Parallel to the minibuffer prompt, a calendar is popped up@footnote{If you do not need/want the calendar, configure the variable
@code{org-popup-calendar-for-date-prompt}.}.
When you exit the date prompt, either by clicking on a date in the
calendar, or by pressing @kbd{@key{RET}}, the date selected in the
calendar is combined with the information entered at the prompt.  You
can control the calendar fully from the minibuffer:

@kindex <
@kindex >
@kindex M-v
@kindex C-v
@kindex mouse-1
@kindex S-RIGHT
@kindex S-LEFT
@kindex S-DOWN
@kindex S-UP
@kindex M-S-RIGHT
@kindex M-S-LEFT
@kindex RET
@multitable @columnfractions 0.25 0.55
@item @kbd{@key{RET}}
@tab Choose date at point in calendar.
@item @kbd{mouse-1}
@tab Select date by clicking on it.
@item @kbd{S-@key{RIGHT}}
@tab One day forward.
@item @kbd{S-@key{LEFT}}
@tab One day backward.
@item @kbd{S-@key{DOWN}}
@tab One week forward.
@item @kbd{S-@key{UP}}
@tab One week backward.
@item @kbd{M-S-@key{RIGHT}}
@tab One month forward.
@item @kbd{M-S-@key{LEFT}}
@tab One month backward.
@item @kbd{>}
@tab Scroll calendar forward by one month.
@item @kbd{<}
@tab Scroll calendar backward by one month.
@item @kbd{M-v}
@tab Scroll calendar forward by 3 months.
@item @kbd{C-v}
@tab Scroll calendar backward by 3 months.
@end multitable

@vindex org-read-date-display-live
The actions of the date/time prompt may seem complex, but I assure you
they will grow on you, and you will start getting annoyed by pretty
much any other way of entering a date/time out there.  To help you
understand what is going on, the current interpretation of your input
is displayed live in the minibuffer@footnote{If you find this distracting, turn off the display with
@code{org-read-date-display-live}.}.

@node Custom time format
@subsection Custom time format

@cindex custom date/time format
@cindex time format, custom
@cindex date format, custom

@vindex org-display-custom-times
@vindex org-time-stamp-custom-formats
Org mode uses the standard ISO notation for dates and times as it is
defined in ISO 8601.  If you cannot get used to this and require
another representation of date and time to keep you happy, you can get
it by customizing the variables @code{org-display-custom-times} and
@code{org-time-stamp-custom-formats}.

@table @asis
@item @kbd{C-c C-x C-t} (@code{org-toggle-time-stamp-overlays})
@kindex C-c C-x C-t
@findex org-toggle-time-stamp-overlays
Toggle the display of custom formats for dates and times.
@end table

Org mode needs the default format for scanning, so the custom
date/time format does not @emph{replace} the default format.  Instead, it
is put @emph{over} the default format using text properties.  This has the
following consequences:

@itemize
@item
You cannot place point onto a timestamp anymore, only before or
after.

@item
The @kbd{S-@key{UP}} and @kbd{S-@key{DOWN}} keys can no longer be used
to adjust each component of a timestamp.  If point is at the
beginning of the stamp, @kbd{S-@key{UP}} and @kbd{S-@key{DOWN}} change
the stamp by one day, just like @kbd{S-@key{LEFT}}
@kbd{S-@key{RIGHT}}.  At the end of the stamp, change the time by one
minute.

@item
If the timestamp contains a range of clock times or a repeater,
these are not overlaid, but remain in the buffer as they were.

@item
When you delete a timestamp character-by-character, it only
disappears from the buffer after @emph{all} (invisible) characters
belonging to the ISO timestamp have been removed.

@item
If the custom timestamp format is longer than the default and you
are using dates in tables, table alignment will be messed up.  If
the custom format is shorter, things do work as expected.
@end itemize

@node Deadlines and Scheduling
@section Deadlines and Scheduling

A timestamp may be preceded by special keywords to facilitate
planning.  Both the timestamp and the keyword have to be positioned
immediately after the task they refer to.

@table @asis
@item @samp{DEADLINE}
@cindex @samp{DEADLINE} marker
Meaning: the task---most likely a TODO item, though not
necessarily---is supposed to be finished on that date.

@vindex org-deadline-warning-days
On the deadline date, the task is listed in the agenda.  In
addition, the agenda for @emph{today} carries a warning about the
approaching or missed deadline, starting @code{org-deadline-warning-days}
before the due date, and continuing until the entry is marked as
done.  An example:

@example
*** TODO write article about the Earth for the Guide
    DEADLINE: <2004-02-29 Sun>
    The editor in charge is [[bbdb:Ford Prefect]]
@end example

@vindex org-agenda-skip-deadline-prewarning-if-scheduled
You can specify a different lead time for warnings for a specific
deadlines using the following syntax.  Here is an example with
a warning period of 5 days @samp{DEADLINE: <2004-02-29 Sun -5d>}.  This
warning is deactivated if the task gets scheduled and you set
@code{org-agenda-skip-deadline-prewarning-if-scheduled} to @code{t}.

@item @samp{SCHEDULED}
@cindex @samp{SCHEDULED} marker
Meaning: you are planning to start working on that task on the given
date.

@vindex org-agenda-skip-scheduled-if-done
The headline is listed under the given date@footnote{It will still be listed on that date after it has been marked
as done.  If you do not like this, set the variable
@code{org-agenda-skip-scheduled-if-done}.}.  In addition,
a reminder that the scheduled date has passed is present in the
compilation for @emph{today}, until the entry is marked as done, i.e.,
the task is automatically forwarded until completed.

@example
*** TODO Call Trillian for a date on New Years Eve.
    SCHEDULED: <2004-12-25 Sat>
@end example

@vindex org-scheduled-delay-days
@vindex org-agenda-skip-scheduled-delay-if-deadline
If you want to @emph{delay} the display of this task in the agenda, use
@samp{SCHEDULED: <2004-12-25 Sat -2d>}: the task is still scheduled on
the 25th but will appear two days later.  In case the task contains
a repeater, the delay is considered to affect all occurrences; if
you want the delay to only affect the first scheduled occurrence of
the task, use @samp{--2d} instead.  See @code{org-scheduled-delay-days} and
@code{org-agenda-skip-scheduled-delay-if-deadline} for details on how to
control this globally or per agenda.

@quotation Important
Scheduling an item in Org mode should @emph{not} be understood in the
same way that we understand @emph{scheduling a meeting}.  Setting a date
for a meeting is just a simple appointment, you should mark this
entry with a simple plain timestamp, to get this item shown on the
date where it applies.  This is a frequent misunderstanding by Org
users.  In Org mode, @emph{scheduling} means setting a date when you want
to start working on an action item.

@end quotation
@end table

You may use timestamps with repeaters in scheduling and deadline
entries.  Org mode issues early and late warnings based on the
assumption that the timestamp represents the @emph{nearest instance} of the
repeater.  However, the use of diary expression entries like

@example
<%%(diary-float t 42)>
@end example


@noindent
in scheduling and deadline timestamps is limited.  Org mode does not
know enough about the internals of each function to issue early and
late warnings.  However, it shows the item on each day where the
expression entry matches.

@menu
* Inserting deadline/schedule::  Planning items.
* Repeated tasks::               Items that show up again and again.
@end menu

@node Inserting deadline/schedule
@subsection Inserting deadlines or schedules

The following commands allow you to quickly insert a deadline or to
schedule an item:@footnote{The @samp{SCHEDULED} and @samp{DEADLINE} dates are inserted on the line
right below the headline.  Do not put any text between this line and
the headline.}

@table @asis
@item @kbd{C-c C-d} (@code{org-deadline})
@kindex C-c C-d
@findex org-deadline
@vindex org-log-redeadline
Insert @samp{DEADLINE} keyword along with a stamp.  The insertion happens
in the line directly following the headline.  Remove any @samp{CLOSED}
timestamp .  When called with a prefix argument, also remove any
existing deadline from the entry.  Depending on the variable
@code{org-log-redeadline}, take a note when changing an existing
deadline@footnote{Note the corresponding @samp{STARTUP} options @samp{logredeadline},
@samp{lognoteredeadline}, and @samp{nologredeadline}.}.

@item @kbd{C-c C-s} (@code{org-schedule})
@kindex C-c C-s
@findex org-schedule
@vindex org-log-reschedule
Insert @samp{SCHEDULED} keyword along with a stamp.  The insertion
happens in the line directly following the headline.  Remove any
@samp{CLOSED} timestamp.  When called with a prefix argument, also remove
the scheduling date from the entry.  Depending on the variable
@code{org-log-reschedule}, take a note when changing an existing
scheduling time@footnote{Note the corresponding @samp{STARTUP} options @samp{logreschedule},
@samp{lognotereschedule}, and @samp{nologreschedule}.}.

@item @kbd{C-c / d} (@code{org-check-deadlines})
@kindex C-c / d
@findex org-check-deadlines
@cindex sparse tree, for deadlines
@vindex org-deadline-warning-days
Create a sparse tree with all deadlines that are either past-due, or
which will become due within @code{org-deadline-warning-days}.  With
@kbd{C-u} prefix, show all deadlines in the file.  With
a numeric prefix, check that many days.  For example, @kbd{C-1 C-c / d} shows all deadlines due tomorrow.

@item @kbd{C-c / b} (@code{org-check-before-date})
@kindex C-c / b
@findex org-check-before-date
Sparse tree for deadlines and scheduled items before a given date.

@item @kbd{C-c / a} (@code{org-check-after-date})
@kindex C-c / a
@findex org-check-after-date
Sparse tree for deadlines and scheduled items after a given date.
@end table

Note that @code{org-schedule} and @code{org-deadline} supports setting the date
by indicating a relative time e.g., @samp{+1d} sets the date to the next
day after today, and @samp{--1w} sets the date to the previous week before
any current timestamp.

@node Repeated tasks
@subsection Repeated tasks

@cindex tasks, repeated
@cindex repeated tasks

Some tasks need to be repeated again and again.  Org mode helps to
organize such tasks using a so-called repeater in a @samp{DEADLINE},
@samp{SCHEDULED}, or plain timestamps@footnote{Org does not repeat inactive timestamps, however.  See
@ref{Timestamps}.}.  In the following example:

@example
** TODO Pay the rent
   DEADLINE: <2005-10-01 Sat +1m>
@end example

@noindent
the @samp{+1m} is a repeater; the intended interpretation is that the task
has a deadline on @samp{<2005-10-01>} and repeats itself every (one) month
starting from that time.  You can use yearly, monthly, weekly, daily
and hourly repeat cookies by using the @samp{y}, @samp{w}, @samp{m}, @samp{d} and @samp{h}
letters.  If you need both a repeater and a special warning period in
a deadline entry, the repeater should come first and the warning
period last

@example
DEADLINE: <2005-10-01 Sat +1m -3d>
@end example


@vindex org-todo-repeat-to-state
Deadlines and scheduled items produce entries in the agenda when they
are over-due, so it is important to be able to mark such an entry as
done once you have done so.  When you mark a @samp{DEADLINE} or
a @samp{SCHEDULED} with the TODO keyword @samp{DONE}, it no longer produces
entries in the agenda.  The problem with this is, however, is that
then also the @emph{next} instance of the repeated entry will not be
active.  Org mode deals with this in the following way: when you try
to mark such an entry as done, using @kbd{C-c C-t}, it shifts the
base date of the repeating timestamp by the repeater interval, and
immediately sets the entry state back to TODO@footnote{In fact, the target state is taken from, in this sequence, the
@samp{REPEAT_TO_STATE} property, the variable @code{org-todo-repeat-to-state} if
it is a string, the previous TODO state if @code{org-todo-repeat-to-state}
is @code{t}, or the first state of the TODO state sequence.}.  In the example
above, setting the state to @samp{DONE} would actually switch the date like
this:

@example
** TODO Pay the rent
   DEADLINE: <2005-11-01 Tue +1m>
@end example

To mark a task with a repeater as DONE, use @kbd{C-- 1 C-c C-t},
i.e., @code{org-todo} with a numeric prefix argument of @samp{-1}.

@vindex org-log-repeat
A timestamp@footnote{You can change this using the option @code{org-log-repeat}, or the
@samp{STARTUP} options @samp{logrepeat}, @samp{lognoterepeat}, and @samp{nologrepeat}.
With @samp{lognoterepeat}, you will also be prompted for a note.} is added under the deadline, to keep a record that
you actually acted on the previous instance of this deadline.

As a consequence of shifting the base date, this entry is no longer
visible in the agenda when checking past dates, but all future
instances will be visible.

With the @samp{+1m} cookie, the date shift is always exactly one month.  So
if you have not paid the rent for three months, marking this entry
DONE still keeps it as an overdue deadline.  Depending on the task,
this may not be the best way to handle it.  For example, if you forgot
to call your father for 3 weeks, it does not make sense to call him
3 times in a single day to make up for it.  Finally, there are tasks
like changing batteries which should always repeat a certain time
@emph{after} the last time you did it.  For these tasks, Org mode has
special repeaters @samp{++} and @samp{.+}.  For example:

@example
** TODO Call Father
   DEADLINE: <2008-02-10 Sun ++1w>
   Marking this DONE shifts the date by at least one week, but also
   by as many weeks as it takes to get this date into the future.
   However, it stays on a Sunday, even if you called and marked it
   done on Saturday.

** TODO Empty kitchen trash
   DEADLINE: <2008-02-08 Fri 20:00 ++1d>
   Marking this DONE shifts the date by at least one day, and also
   by as many days as it takes to get the timestamp into the future.
   Since there is a time in the timestamp, the next deadline in the
   future will be on today's date if you complete the task before
   20:00.

** TODO Check the batteries in the smoke detectors
   DEADLINE: <2005-11-01 Tue .+1m>
   Marking this DONE will shift the date to one month after today.
@end example

@vindex org-agenda-skip-scheduled-if-deadline-is-shown
You may have both scheduling and deadline information for a specific
task.  If the repeater is set for the scheduling information only, you
probably want the repeater to be ignored after the deadline.  If so,
set the variable @code{org-agenda-skip-scheduled-if-deadline-is-shown} to
@code{repeated-after-deadline}.  However, any scheduling information
without a repeater is no longer relevant once the task is done, and
thus, removed upon repeating the task.  If you want both scheduling
and deadline information to repeat after the same interval, set the
same repeater for both timestamps.

An alternative to using a repeater is to create a number of copies of
a task subtree, with dates shifted in each copy.  The command
@kbd{C-c C-x c} was created for this purpose; it is described in
@ref{Structure Editing}.

@node Clocking Work Time
@section Clocking Work Time

@cindex clocking time
@cindex time clocking

Org mode allows you to clock the time you spend on specific tasks in
a project.  When you start working on an item, you can start the
clock.  When you stop working on that task, or when you mark the task
done, the clock is stopped and the corresponding time interval is
recorded.  It also computes the total time spent on each
subtree@footnote{Clocking only works if all headings are indented with less
than 30 stars.  This is a hard-coded limitation of @code{lmax} in
@code{org-clock-sum}.} of a project.  And it remembers a history or tasks
recently clocked, to that you can jump quickly between a number of
tasks absorbing your time.

To save the clock history across Emacs sessions, use:

@lisp
(setq org-clock-persist 'history)
(org-clock-persistence-insinuate)
@end lisp

@vindex org-clock-persist
When you clock into a new task after resuming Emacs, the incomplete
clock@footnote{To resume the clock under the assumption that you have worked
on this task while outside Emacs, use @samp{(setq org-clock-persist t)}.} is retrieved (see @ref{Resolving idle time (1)}) and you are
prompted about what to do with it.

@menu
* Clocking commands::            Starting and stopping a clock.
* The clock table::              Detailed reports.
* Resolving idle time::          Resolving time when you've been idle.
@end menu

@node Clocking commands
@subsection Clocking commands

@table @asis
@item @kbd{C-c C-x C-i} (@code{org-clock-in})
@kindex C-c C-x C-i
@findex org-clock-in
@vindex org-clock-into-drawer
@vindex org-clock-continuously
@cindex @samp{LOG_INTO_DRAWER}, property
Start the clock on the current item (clock-in).  This inserts the
@samp{CLOCK} keyword together with a timestamp.  If this is not the first
clocking of this item, the multiple @samp{CLOCK} lines are wrapped into
a @samp{LOGBOOK} drawer (see also the variable @code{org-clock-into-drawer}).
You can also overrule the setting of this variable for a subtree by
setting a @samp{CLOCK_INTO_DRAWER} or @samp{LOG_INTO_DRAWER} property.  When
called with a @kbd{C-u} prefix argument, select the task from
a list of recently clocked tasks.  With two @kbd{C-u C-u}
prefixes, clock into the task at point and mark it as the default
task; the default task is always be available with letter
@kbd{d} when selecting a clocking task.  With three @kbd{C-u C-u C-u} prefixes, force continuous clocking by starting the
clock when the last clock stopped.

@cindex @samp{CLOCK_MODELINE_TOTAL}, property
@cindex @samp{LAST_REPEAT}, property
@vindex org-clock-mode-line-total
@vindex org-clock-in-prepare-hook
While the clock is running, Org shows the current clocking time in
the mode line, along with the title of the task.  The clock time
shown is all time ever clocked for this task and its children.  If
the task has an effort estimate (see @ref{Effort Estimates}), the mode
line displays the current clocking time against it@footnote{To add an effort estimate ``on the fly'', hook a function doing
this to @code{org-clock-in-prepare-hook}.}.  If the
task is a repeating one (see @ref{Repeated tasks}), show only the time
since the last reset of the task@footnote{The last reset of the task is recorded by the @samp{LAST_REPEAT}
property.}.  You can exercise more
control over show time with the @samp{CLOCK_MODELINE_TOTAL} property.  It
may have the values @samp{current} to show only the current clocking
instance, @samp{today} to show all time clocked on this tasks today---see
also the variable @code{org-extend-today-until}, @code{all} to include all
time, or @code{auto} which is the default@footnote{See also the variable @code{org-clock-mode-line-total}.}.  Clicking with
@kbd{mouse-1} onto the mode line entry pops up a menu with
clocking options.

@item @kbd{C-c C-x C-o} (@code{org-clock-out})
@kindex C-c C-x C-o
@findex org-clock-out
@vindex org-log-note-clock-out
Stop the clock (clock-out).  This inserts another timestamp at the
same location where the clock was last started.  It also directly
computes the resulting time in inserts it after the time range as
@samp{=>HH:MM}.  See the variable @code{org-log-note-clock-out} for the
possibility to record an additional note together with the clock-out
timestamp@footnote{The corresponding in-buffer setting is: @samp{#+STARTUP:
lognoteclock-out}.}.

@item @kbd{C-c C-x C-x} (@code{org-clock-in-last})
@kindex C-c C-x C-x
@findex org-clock-in-last
@vindex org-clock-continuously
Re-clock the last clocked task.  With one @kbd{C-u} prefix
argument, select the task from the clock history.  With two
@kbd{C-u} prefixes, force continuous clocking by starting the
clock when the last clock stopped.

@item @kbd{C-c C-x C-e} (@code{org-clock-modify-effort-estimate})
@kindex C-c C-x C-e
@findex org-clock-modify-effort-estimate
Update the effort estimate for the current clock task.

@item @kbd{C-c C-c} or @kbd{C-c C-y} (@code{org-evaluate-time-range})
@kindex C-c C-c
@kindex C-c C-y
@findex org-evaluate-time-range
Recompute the time interval after changing one of the timestamps.
This is only necessary if you edit the timestamps directly.  If you
change them with @kbd{S-<cursor>} keys, the update is
automatic.

@item @kbd{C-S-@key{UP}} (@code{org-clock-timestamps-up})
@itemx @kbd{C-S-@key{DOWN}} (@code{org-clock-timestamps-down})
@kindex C-S-UP
@findex org-clock-timestamps-up
@kindex C-S-DOWN
@findex org-clock-timestamps-down
On CLOCK log lines, increase/decrease both timestamps so that the
clock duration keeps the same value.

@item @kbd{S-M-@key{UP}} (@code{org-timestamp-up})
@itemx @kbd{S-M-@key{DOWN}} (@code{org-timestamp-down})
@kindex S-M-UP
@findex org-clock-timestamp-up
@kindex S-M-DOWN
@findex org-clock-timestamp-down
On @samp{CLOCK} log lines, increase/decrease the timestamp at point and
the one of the previous, or the next, clock timestamp by the same
duration.  For example, if you hit @kbd{S-M-@key{UP}} to increase
a clocked-out timestamp by five minutes, then the clocked-in
timestamp of the next clock is increased by five minutes.

@item @kbd{C-c C-t} (@code{org-todo})
@kindex C-c C-t
@findex org-todo
Changing the TODO state of an item to DONE automatically stops the
clock if it is running in this same item.

@item @kbd{C-c C-x C-q} (@code{org-clock-cancel})
@kindex C-c C-x C-q
@findex org-clock-cancel
Cancel the current clock.  This is useful if a clock was started by
mistake, or if you ended up working on something else.

@item @kbd{C-c C-x C-j} (@code{org-clock-goto})
@kindex C-c C-x C-j
@findex or-clock-goto
Jump to the headline of the currently clocked in task.  With
a @kbd{C-u} prefix argument, select the target task from a list
of recently clocked tasks.

@item @kbd{C-c C-x C-d} (@code{org-clock-display})
@kindex C-c C-x C-d
@findex org-clock-display
@vindex org-remove-highlights-with-change
Display time summaries for each subtree in the current buffer.  This
puts overlays at the end of each headline, showing the total time
recorded under that heading, including the time of any subheadings.
You can use visibility cycling to study the tree, but the overlays
disappear when you change the buffer (see variable
@code{org-remove-highlights-with-change}) or press @kbd{C-c C-c}.
@end table

The @kbd{l} key may be used in the agenda (see @ref{Weekly/daily agenda}) to show which tasks have been worked on or closed during
a day.

@strong{Important:} note that both @code{org-clock-out} and @code{org-clock-in-last}
can have a global keybinding and do not modify the window disposition.

@node The clock table
@subsection The clock table

@cindex clocktable, dynamic block
@cindex report, of clocked time

Org mode can produce quite complex reports based on the time clocking
information.  Such a report is called a @emph{clock table}, because it is
formatted as one or several Org tables.

You can insert, or update, a clock table through Org dynamic blocks
insert command (see @ref{Dynamic Blocks}), by pressing @kbd{C-c C-x x c l o c k t a b l e @key{RET}}.  When called with a prefix argument,
jump to the first clock table in the current document and update it.
The clock table includes archived trees.

@table @asis
@item @kbd{C-c C-c} or @kbd{C-c C-x C-u} (@code{org-dblock-update})
@kindex C-c C-c
@kindex C-c C-x C-u
@findex org-dblock-update
Update dynamic block at point.  Point needs to be in the @samp{BEGIN}
line of the dynamic block.

@item @kbd{C-u C-c C-x C-u}
@kindex C-u C-c C-x C-u
Update all dynamic blocks (see @ref{Dynamic Blocks}).  This is useful if
you have several clock table blocks in a buffer.

@item @kbd{S-@key{LEFT}}
@itemx @kbd{S-@key{RIGHT}} (@code{org-clocktable-try-shift})
@kindex S-LEFT
@kindex S-RIGHT
@findex org-clocktable-try-shift
Shift the current @samp{:block} interval and update the table.  Point
needs to be in the @samp{#+BEGIN: clocktable} line for this command.  If
@samp{:block} is @samp{today}, it is shifted to @samp{today-1}, etc.
@end table

Here is an example of the frame for a clock table as it is inserted
into the buffer with the @kbd{C-c C-x C-r} command:

@cindex @samp{BEGIN clocktable}
@example
#+BEGIN: clocktable :maxlevel 2 :emphasize nil :scope file
#+END: clocktable
@end example

@vindex org-clocktable-defaults
The @samp{#+BEGIN} line and specify a number of options to define the
scope, structure, and formatting of the report.  Defaults for all
these options can be configured in the variable
@code{org-clocktable-defaults}.

First there are options that determine which clock entries are to
be selected:

@table @asis
@item @samp{:maxlevel}
Maximum level depth to which times are listed in the table.  Clocks
at deeper levels are summed into the upper level.

@item @samp{:scope}
The scope to consider.  This can be any of the following:

@multitable {aaaaaaaaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{nil}
@tab the current buffer or narrowed region
@item @samp{file}
@tab the full current buffer
@item @samp{subtree}
@tab the subtree where the clocktable is located
@item @samp{treeN}
@tab the surrounding level N tree, for example @samp{tree3}
@item @samp{tree}
@tab the surrounding level 1 tree
@item @samp{agenda}
@tab all agenda files
@item @samp{("file" ...)}
@tab scan these files
@item @samp{FUNCTION}
@tab scan files returned by calling @var{FUNCTION} with no argument
@item @samp{file-with-archives}
@tab current file and its archives
@item @samp{agenda-with-archives}
@tab all agenda files, including archives
@end multitable

@item @samp{:block}
The time block to consider.  This block is specified either
absolutely, or relative to the current time and may be any of these
formats:

@multitable {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaa}
@item @samp{2007-12-31}
@tab New year eve 2007
@item @samp{2007-12}
@tab December 2007
@item @samp{2007-W50}
@tab ISO-week 50 in 2007
@item @samp{2007-Q2}
@tab 2nd quarter in 2007
@item @samp{2007}
@tab the year 2007
@item @samp{today}, @samp{yesterday}, @samp{today-N}
@tab a relative day
@item @samp{thisweek}, @samp{lastweek}, @samp{thisweek-N}
@tab a relative week
@item @samp{thismonth}, @samp{lastmonth}, @samp{thismonth-N}
@tab a relative month
@item @samp{thisyear}, @samp{lastyear}, @samp{thisyear-N}
@tab a relative year
@item @samp{untilnow}@footnote{When using @code{:step}, @code{untilnow} starts from the beginning of
2003, not the beginning of time.}
@tab all clocked time ever
@end multitable

@vindex org-clock-display-default-range
When this option is not set, Org falls back to the value in
@code{org-clock-display-default-range}, which defaults to the current
year.

Use @kbd{S-@key{LEFT}} or @kbd{S-@key{RIGHT}} to shift the time
interval.

@item @samp{:tstart}
A time string specifying when to start considering times.  Relative
times like @samp{"<-2w>"} can also be used.  See @ref{Matching tags and properties} for relative time syntax.

@item @samp{:tend}
A time string specifying when to stop considering times.  Relative
times like @samp{"<now>"} can also be used.  See @ref{Matching tags and properties} for relative time syntax.

@item @samp{:wstart}
The starting day of the week.  The default is 1 for Monday.

@item @samp{:mstart}
The starting day of the month.  The default is 1 for the first.

@item @samp{:step}
Set to @samp{day}, @samp{week}, @samp{month} or @samp{year} to split the table into
chunks.  To use this, either @samp{:block}, or @samp{:tstart} and @samp{:tend} are
required.

@item @samp{:stepskip0}
When non-@code{nil}, do not show steps that have zero time.

@item @samp{:fileskip0}
When non-@code{nil}, do not show table sections from files which did not
contribute.

@item @samp{:match}
A tags match to select entries that should contribute.  See
@ref{Matching tags and properties} for the match syntax.
@end table

@findex org-clocktable-write-default
Then there are options that determine the formatting of the table.
There options are interpreted by the function
@code{org-clocktable-write-default}, but you can specify your own function
using the @samp{:formatter} parameter.

@table @asis
@item @samp{:emphasize}
When non-@code{nil}, emphasize level one and level two items.

@item @samp{:lang}
Language@footnote{Language terms can be set through the variable
@code{org-clock-clocktable-language-setup}.} to use for descriptive cells like ``Task''.

@item @samp{:link}
Link the item headlines in the table to their origins.

@item @samp{:narrow}
An integer to limit the width of the headline column in the Org
table.  If you write it like @samp{50!}, then the headline is also
shortened in export.

@item @samp{:indent}
Indent each headline field according to its level.

@item @samp{:hidefiles}
Hide the file column when multiple files are used to produce the
table.

@item @samp{:tcolumns}
Number of columns to be used for times.  If this is smaller than
@samp{:maxlevel}, lower levels are lumped into one column.

@item @samp{:level}
Should a level number column be included?

@item @samp{:sort}
A cons cell containing the column to sort and a sorting type.  E.g.,
@samp{:sort (1 . ?a)} sorts the first column alphabetically.

@item @samp{:compact}
Abbreviation for @samp{:level nil :indent t :narrow 40! :tcolumns 1}.
All are overwritten except if there is an explicit @samp{:narrow}.

@item @samp{:timestamp}
A timestamp for the entry, when available.  Look for @samp{SCHEDULED},
@samp{DEADLINE}, @samp{TIMESTAMP} and @samp{TIMESTAMP_IA} special properties (see
@ref{Special Properties}), in this order.

@item @samp{:tags}
When this flag is non-@code{nil}, show the headline's tags.

@item @samp{:properties}
List of properties shown in the table.  Each property gets its own
column.

@item @samp{:inherit-props}
When this flag is non-@code{nil}, the values for @samp{:properties} are
inherited.

@item @samp{:formula}
Content of a @samp{TBLFM} keyword to be added and evaluated.  As
a special case, @samp{:formula %} adds a column with % time.  If you do
not specify a formula here, any existing formula below the clock
table survives updates and is evaluated.

@item @samp{:formatter}
A function to format clock data and insert it into the buffer.
@end table

To get a clock summary of the current level 1 tree, for the current
day, you could write:

@example
#+BEGIN: clocktable :maxlevel 2 :block today :scope tree1 :link t
#+END: clocktable
@end example

@noindent
To use a specific time range you could write@footnote{Note that all parameters must be specified in a single
line---the line is broken here only to fit it into the manual.}

@example
#+BEGIN: clocktable :tstart "<2006-08-10 Thu 10:00>"
                    :tend "<2006-08-10 Thu 12:00>"
#+END: clocktable
@end example

@noindent
A range starting a week ago and ending right now could be written as

@example
#+BEGIN: clocktable :tstart "<-1w>" :tend "<now>"
#+END: clocktable
@end example

@noindent
A summary of the current subtree with % times would be

@example
#+BEGIN: clocktable :scope subtree :link t :formula %
#+END: clocktable
@end example

@noindent
A horizontally compact representation of everything clocked during
last week would be

@example
#+BEGIN: clocktable :scope agenda :block lastweek :compact t
#+END: clocktable
@end example

@node Resolving idle time
@subsection Resolving idle time and continuous clocking



@anchor{Resolving idle time (1)}
@subsubheading Resolving idle time

@cindex resolve idle time
@cindex idle, resolve, dangling

If you clock in on a work item, and then walk away from your
computer---perhaps to take a phone call---you often need to
``resolve'' the time you were away by either subtracting it from the
current clock, or applying it to another one.

@vindex org-clock-idle-time
@vindex org-clock-x11idle-program-name
By customizing the variable @code{org-clock-idle-time} to some integer,
such as 10 or 15, Emacs can alert you when you get back to your
computer after being idle for that many minutes@footnote{On computers using macOS, idleness is based on actual user
idleness, not just Emacs' idle time.  For X11, you can install
a utility program @samp{x11idle.c}, available in the @samp{contrib/scripts/}
directory of the Org Git distribution, or install the xprintidle
package and set it to the variable @code{org-clock-x11idle-program-name} if
you are running Debian, to get the same general treatment of idleness.
On other systems, idle time refers to Emacs idle time only.}, and ask what
you want to do with the idle time.  There will be a question waiting
for you when you get back, indicating how much idle time has passed
constantly updated with the current amount, as well as a set of
choices to correct the discrepancy:

@table @asis
@item @kbd{k}
@kindex k
To keep some or all of the minutes and stay clocked in, press
@kbd{k}.  Org asks how many of the minutes to keep.  Press
@kbd{@key{RET}} to keep them all, effectively changing nothing, or
enter a number to keep that many minutes.

@item @kbd{K}
@kindex K
If you use the shift key and press @kbd{K}, it keeps however
many minutes you request and then immediately clock out of that
task.  If you keep all of the minutes, this is the same as just
clocking out of the current task.

@item @kbd{s}
@kindex s
To keep none of the minutes, use @kbd{s} to subtract all the
away time from the clock, and then check back in from the moment you
returned.

@item @kbd{S}
@kindex S
To keep none of the minutes and just clock out at the start of the
away time, use the shift key and press @kbd{S}.  Remember that
using shift always leave you clocked out, no matter which option you
choose.

@item @kbd{C}
@kindex C
To cancel the clock altogether, use @kbd{C}.  Note that if
instead of canceling you subtract the away time, and the resulting
clock amount is less than a minute, the clock is still canceled
rather than cluttering up the log with an empty entry.
@end table

What if you subtracted those away minutes from the current clock, and
now want to apply them to a new clock?  Simply clock in to any task
immediately after the subtraction.  Org will notice that you have
subtracted time ``on the books'', so to speak, and will ask if you want
to apply those minutes to the next task you clock in on.

There is one other instance when this clock resolution magic occurs.
Say you were clocked in and hacking away, and suddenly your cat chased
a mouse who scared a hamster that crashed into your UPS's power
button!  You suddenly lose all your buffers, but thanks to auto-save
you still have your recent Org mode changes, including your last clock
in.

If you restart Emacs and clock into any task, Org will notice that you
have a dangling clock which was never clocked out from your last
session.  Using that clock's starting time as the beginning of the
unaccounted-for period, Org will ask how you want to resolve that
time.  The logic and behavior is identical to dealing with away time
due to idleness; it is just happening due to a recovery event rather
than a set amount of idle time.

You can also check all the files visited by your Org agenda for
dangling clocks at any time using @kbd{M-x org-resolve-clocks @key{RET}} (or @kbd{C-c C-x C-z}).

@anchor{Continuous clocking}
@subsubheading Continuous clocking

@cindex continuous clocking

@vindex org-clock-continuously
You may want to start clocking from the time when you clocked out the
previous task.  To enable this systematically, set
@code{org-clock-continuously} to non-@code{nil}.  Each time you clock in, Org
retrieves the clock-out time of the last clocked entry for this
session, and start the new clock from there.

If you only want this from time to time, use three universal prefix
arguments with @code{org-clock-in} and two @kbd{C-u C-u} with
@code{org-clock-in-last}.

@node Effort Estimates
@section Effort Estimates

@cindex effort estimates
@cindex @samp{EFFORT}, property
@vindex org-effort-property

If you want to plan your work in a very detailed way, or if you need
to produce offers with quotations of the estimated work effort, you
may want to assign effort estimates to entries.  If you are also
clocking your work, you may later want to compare the planned effort
with the actual working time, a great way to improve planning
estimates.  Effort estimates are stored in a special property
@samp{EFFORT}.  You can set the effort for an entry with the following
commands:

@table @asis
@item @kbd{C-c C-x e}  (@code{org-set-effort})
@kindex C-c C-x e
@findex org-set-effort
Set the effort estimate for the current entry.  With a prefix
argument, set it to the next allowed value---see below.  This
command is also accessible from the agenda with the @kbd{e}
key.

@item @kbd{C-c C-x C-e} (@code{org-clock-modify-effort-estimate})
@kindex C-c C-x C-e
@findex org-clock-modify-effort-estimate
Modify the effort estimate of the item currently being clocked.
@end table

Clearly the best way to work with effort estimates is through column
view (see @ref{Column View}).  You should start by setting up discrete
values for effort estimates, and a @samp{COLUMNS} format that displays
these values together with clock sums---if you want to clock your
time.  For a specific buffer you can use:

@example
#+PROPERTY: Effort_ALL 0 0:10 0:30 1:00 2:00 3:00 4:00 5:00 6:00 7:00
#+COLUMNS: %40ITEM(Task) %17Effort(Estimated Effort)@{:@} %CLOCKSUM
@end example

@noindent
@vindex org-global-properties
@vindex org-columns-default-format
or, even better, you can set up these values globally by customizing
the variables @code{org-global-properties} and
@code{org-columns-default-format}.  In particular if you want to use this
setup also in the agenda, a global setup may be advised.

The way to assign estimates to individual items is then to switch to
column mode, and to use @kbd{S-@key{RIGHT}} and @kbd{S-@key{LEFT}} to
change the value.  The values you enter are immediately summed up in
the hierarchy.  In the column next to it, any clocked time is
displayed.

@vindex org-agenda-columns-add-appointments-to-effort-sum
If you switch to column view in the daily/weekly agenda, the effort
column summarizes the estimated work effort for each day@footnote{Please note the pitfalls of summing hierarchical data in
a flat list (see @ref{Agenda Column View}).}, and
you can use this to find space in your schedule.  To get an overview
of the entire part of the day that is committed, you can set the
option @code{org-agenda-columns-add-appointments-to-effort-sum}.  The
appointments on a day that take place over a specified time interval
are then also added to the load estimate of the day.

Effort estimates can be used in secondary agenda filtering that is
triggered with the @kbd{/} key in the agenda (see @ref{Agenda Commands}).  If you have these estimates defined consistently,
two or three key presses narrow down the list to stuff that fits into
an available time slot.

@node Timers
@section Taking Notes with a Relative Timer

@cindex relative timer
@cindex countdown timer

Org provides two types of timers.  There is a relative timer that
counts up, which can be useful when taking notes during, for example,
a meeting or a video viewing.  There is also a countdown timer.

The relative and countdown are started with separate commands.

@table @asis
@item @kbd{C-c C-x 0} (@code{org-timer-start})
@kindex C-c C-x 0
@findex org-timer-start
Start or reset the relative timer.  By default, the timer is set
to 0.  When called with a @kbd{C-u} prefix, prompt the user for
a starting offset.  If there is a timer string at point, this is
taken as the default, providing a convenient way to restart taking
notes after a break in the process.  When called with a double
prefix argument @kbd{C-u C-u}, change all timer strings in the
active region by a certain amount.  This can be used to fix timer
strings if the timer was not started at exactly the right moment.

@item @kbd{C-c C-x ;} (@code{org-timer-set-timer})
@kindex C-c C-x ;
@findex org-timer-set-timer
@vindex org-timer-default-timer
Start a countdown timer.  The user is prompted for a duration.
@code{org-timer-default-timer} sets the default countdown value.  Giving
a numeric prefix argument overrides this default value.  This
command is available as @kbd{;} in agenda buffers.
@end table

Once started, relative and countdown timers are controlled with the
same commands.

@table @asis
@item @kbd{C-c C-x .} (@code{org-timer})
@kindex C-c C-x .
@findex org-timer
Insert a relative time into the buffer.  The first time you use
this, the timer starts.  Using a prefix argument restarts it.

@item @kbd{C-c C-x -} (@code{org-timer-item})
@kindex C-c C-x -
@findex org-timer-item
Insert a description list item with the current relative time.  With
a prefix argument, first reset the timer to 0.

@item @kbd{M-@key{RET}} (@code{org-insert-heading})
@kindex M-RET
@findex org-insert-heading
Once the timer list is started, you can also use @kbd{M-@key{RET}} to
insert new timer items.

@item @kbd{C-c C-x ,} (@code{org-timer-pause-or-continue})
@kindex C-c C-x ,
@findex org-timer-pause-or-continue
Pause the timer, or continue it if it is already paused.

@item @kbd{C-c C-x _} (@code{org-timer-stop})
@kindex C-c C-x _
@findex org-timer-stop
Stop the timer.  After this, you can only start a new timer, not
continue the old one.  This command also removes the timer from the
mode line.
@end table

@node Refiling and Archiving
@chapter Refiling and Archiving

@cindex refiling notes
@cindex copying notes
@cindex archiving

Once information is in the system, it may need to be moved around.
Org provides Refile, Copy and Archive commands for this.  Refile and
Copy helps with moving and copying outlines.  Archiving helps to keep
the system compact and fast.

@menu
* Refile and Copy::              Moving/copying a tree from one place to another.
* Archiving::                    What to do with finished products.
@end menu

@node Refile and Copy
@section Refile and Copy

@cindex refiling notes
@cindex copying notes

When reviewing the captured data, you may want to refile or to copy
some of the entries into a different list, for example into a project.
Cutting, finding the right location, and then pasting the note is
cumbersome.  To simplify this process, you can use the following
special command:

@table @asis
@item @kbd{C-c C-w} (@code{org-refile})
@kindex C-c C-w
@findex org-refile
@vindex org-reverse-note-order
@vindex org-refile-targets
@vindex org-refile-use-outline-path
@vindex org-outline-path-complete-in-steps
@vindex org-refile-allow-creating-parent-nodes
@vindex org-log-refile
Refile the entry or region at point.  This command offers possible
locations for refiling the entry and lets you select one with
completion.  The item (or all items in the region) is filed below
the target heading as a subitem.  Depending on
@code{org-reverse-note-order}, it is either the first or last subitem.

By default, all level 1 headlines in the current buffer are
considered to be targets, but you can have more complex definitions
across a number of files.  See the variable @code{org-refile-targets} for
details.  If you would like to select a location via
a file-path-like completion along the outline path, see the
variables @code{org-refile-use-outline-path} and
@code{org-outline-path-complete-in-steps}.  If you would like to be able
to create new nodes as new parents for refiling on the fly, check
the variable @code{org-refile-allow-creating-parent-nodes}.  When the
variable @code{org-log-refile}@footnote{Note the corresponding @samp{STARTUP} options @samp{logrefile},
@samp{lognoterefile}, and @samp{nologrefile}.} is set, a timestamp or a note is
recorded whenever an entry is refiled.

@item @kbd{C-u C-c C-w}
@kindex C-u C-c C-w
Use the refile interface to jump to a heading.

@item @kbd{C-u C-u C-c C-w} (@code{org-refile-goto-last-stored})
@kindex C-u C-u C-c C-w
@findex org-refile-goto-last-stored
Jump to the location where @code{org-refile} last moved a tree to.

@item @kbd{C-2 C-c C-w}
@kindex C-2 C-c C-w
Refile as the child of the item currently being clocked.

@item @kbd{C-3 C-c C-w}
@kindex C-3 C-c C-w
@vindex org-refile-keep
Refile and keep the entry in place.  Also see @code{org-refile-keep} to
make this the default behavior, and beware that this may result in
duplicated @samp{ID} properties.

@item @kbd{C-0 C-c C-w} or @kbd{C-u C-u C-u C-c C-w} (@code{org-refile-cache-clear})
@kindex C-u C-u C-u C-c C-w
@kindex C-0 C-c C-w
@findex org-refile-cache-clear
@vindex org-refile-use-cache
Clear the target cache.  Caching of refile targets can be turned on
by setting @code{org-refile-use-cache}.  To make the command see new
possible targets, you have to clear the cache with this command.

@item @kbd{C-c M-w} (@code{org-copy})
@kindex C-c M-w
@findex org-copy
Copying works like refiling, except that the original note is not
deleted.
@end table

@node Archiving
@section Archiving

@cindex archiving

When a project represented by a (sub)tree is finished, you may want to
move the tree out of the way and to stop it from contributing to the
agenda.  Archiving is important to keep your working files compact and
global searches like the construction of agenda views fast.

@table @asis
@item @kbd{C-c C-x C-a} (@code{org-archive-subtree-default})
@kindex C-c C-x C-a
@findex org-archive-subtree-default
@vindex org-archive-default-command
Archive the current entry using the command specified in the
variable @code{org-archive-default-command}.
@end table

@menu
* Moving subtrees::              Moving a tree to an archive file.
* Internal archiving::           Switch off a tree but keep it in the file.
@end menu

@node Moving subtrees
@subsection Moving a tree to an archive file

@cindex external archiving

The most common archiving action is to move a project tree to another
file, the archive file.

@table @asis
@item @kbd{C-c C-x C-s} or short @kbd{C-c $} (@code{org-archive-subtree})
@kindex C-c C-x C-s
@kindex C-c $
@findex org-archive-subtree
@vindex org-archive-location
Archive the subtree starting at point position to the location given
by @code{org-archive-location}.

@item @kbd{C-u C-c C-x C-s}
@kindex C-u C-c C-x C-s
Check if any direct children of the current headline could be moved
to the archive.  To do this, check each subtree for open TODO
entries.  If none is found, the command offers to move it to the
archive location.  If point is @emph{not} on a headline when this command
is invoked, check level 1 trees.

@item @kbd{C-u C-u C-c C-x C-s}
@kindex C-u C-u C-c C-x C-s
As above, but check subtree for timestamps instead of TODO entries.
The command offers to archive the subtree if it @emph{does} contain
a timestamp, and that timestamp is in the past.
@end table

@cindex archive locations
The default archive location is a file in the same directory as the
current file, with the name derived by appending @samp{_archive} to the
current file name.  You can also choose what heading to file archived
items under, with the possibility to add them to a datetree in a file.
For information and examples on how to specify the file and the
heading, see the documentation string of the variable
@code{org-archive-location}.

There is also an in-buffer option for setting this variable, for
example:

@cindex @samp{ARCHIVE}, keyword
@example
#+ARCHIVE: %s_done::
@end example


@cindex ARCHIVE, property
If you would like to have a special archive location for a single
entry or a (sub)tree, give the entry an @samp{ARCHIVE} property with the
location as the value (see @ref{Properties and Columns}).

@vindex org-archive-save-context-info
When a subtree is moved, it receives a number of special properties
that record context information like the file from where the entry
came, its outline path the archiving time etc.  Configure the variable
@code{org-archive-save-context-info} to adjust the amount of information
added.

@node Internal archiving
@subsection Internal archiving

@cindex @samp{ARCHIVE}, tag
If you want to just switch off---for agenda views---certain subtrees
without moving them to a different file, you can use the @samp{ARCHIVE}
tag.

A headline that is marked with the @samp{ARCHIVE} tag (see @ref{Tags}) stays at
its location in the outline tree, but behaves in the following way:

@itemize
@item
@vindex org-cycle-open-archived-trees
It does not open when you attempt to do so with a visibility cycling
command (see @ref{Visibility Cycling}).  You can force cycling archived
subtrees with @kbd{C-@key{TAB}}, or by setting the option
@code{org-cycle-open-archived-trees}.  Also normal outline commands, like
@code{outline-show-all}, open archived subtrees.

@item
@vindex org-sparse-tree-open-archived-trees
During sparse tree construction (see @ref{Sparse Trees}), matches in
archived subtrees are not exposed, unless you configure the option
@code{org-sparse-tree-open-archived-trees}.

@item
@vindex org-agenda-skip-archived-trees
During agenda view construction (see @ref{Agenda Views}), the content of
archived trees is ignored unless you configure the option
@code{org-agenda-skip-archived-trees}, in which case these trees are
always included.  In the agenda you can press @kbd{v a} to get
archives temporarily included.

@item
@vindex org-export-with-archived-trees
Archived trees are not exported (see @ref{Exporting}), only the headline
is.  Configure the details using the variable
@code{org-export-with-archived-trees}.

@item
@vindex org-columns-skip-archived-trees
Archived trees are excluded from column view unless the variable
@code{org-columns-skip-archived-trees} is configured to @code{nil}.
@end itemize

The following commands help manage the @samp{ARCHIVE} tag:

@table @asis
@item @kbd{C-c C-x a} (@code{org-toggle-archive-tag})
@kindex C-c C-x a
@findex org-toggle-archive-tag
Toggle the archive tag for the current headline.  When the tag is
set, the headline changes to a shadowed face, and the subtree below
it is hidden.

@item @kbd{C-u C-c C-x a}
@kindex C-u C-c C-x a
Check if any direct children of the current headline should be
archived.  To do this, check each subtree for open TODO entries.  If
none is found, the command offers to set the @samp{ARCHIVE} tag for the
child.  If point is @emph{not} on a headline when this command is
invoked, check the level 1 trees.

@item @kbd{C-@key{TAB}} (@code{org-force-cycle-archived})
@kindex C-TAB
Cycle a tree even if it is tagged with @samp{ARCHIVE}.

@item @kbd{C-c C-x A} (@code{org-archive-to-archive-sibling})
@kindex C-c C-x A
@findex org-archive-to-archive-sibling
Move the current entry to the @emph{Archive Sibling}.  This is a sibling
of the entry with the heading @samp{Archive} and the archive tag.  The
entry becomes a child of that sibling and in this way retains a lot
of its original context, including inherited tags and approximate
position in the outline.
@end table

@node Capture and Attachments
@chapter Capture and Attachments

@cindex capture
@cindex attachments
@cindex RSS feeds
@cindex Atom feeds
@cindex protocols, for external access

An important part of any organization system is the ability to quickly
capture new ideas and tasks, and to associate reference material with
them.  Org does this using a process called @emph{capture}.  It also can
store files related to a task (@emph{attachments}) in a special directory.
Finally, it can parse RSS feeds for information.  To learn how to let
external programs (for example a web browser) trigger Org to capture
material, see @ref{Protocols}.

@menu
* Capture::                      Capturing new stuff.
* Attachments::                  Attach files to outlines.
* RSS Feeds::                    Getting input from RSS feeds.
@end menu

@node Capture
@section Capture

@cindex capture

Capture lets you quickly store notes with little interruption of your
work flow.  Org's method for capturing new items is heavily inspired
by John Wiegley's excellent Remember package.

@menu
* Setting up capture::           Where notes will be stored.
* Using capture::                Commands to invoke and terminate capture.
* Capture templates::            Define the outline of different note types.
@end menu

@node Setting up capture
@subsection Setting up capture

The following customization sets a default target file for notes.

@vindex org-default-notes-file
@lisp
(setq org-default-notes-file (concat org-directory "/notes.org"))
@end lisp

You may also define a global key for capturing new material (see
@ref{Activation}).

@node Using capture
@subsection Using capture

@table @asis
@item @kbd{M-x org-capture} (@code{org-capture})
@findex org-capture
@cindex date tree
Display the capture templates menu.  If you have templates defined
(see @ref{Capture templates}), it offers these templates for selection or
use a new Org outline node as the default template.  It inserts the
template into the target file and switch to an indirect buffer
narrowed to this new node.  You may then insert the information you
want.

@item @kbd{C-c C-c} (@code{org-capture-finalize})
@kindex C-c C-c @r{(Capture buffer)}
@findex org-capture-finalize
Once you have finished entering information into the capture buffer,
@kbd{C-c C-c} returns you to the window configuration before
the capture process, so that you can resume your work without
further distraction.  When called with a prefix argument, finalize
and then jump to the captured item.

@item @kbd{C-c C-w} (@code{org-capture-refile})
@kindex C-c C-w @r{(Capture buffer)}
@findex org-capture-refile
Finalize the capture process by refiling the note to a different
place (see @ref{Refile and Copy}).  Please realize that this is a normal
refiling command that will be executed---so point position at the
moment you run this command is important.  If you have inserted
a tree with a parent and children, first move point back to the
parent.  Any prefix argument given to this command is passed on to
the @code{org-refile} command.

@item @kbd{C-c C-k} (@code{org-capture-kill})
@kindex C-c C-k @r{(Capture buffer)}
@findex org-capture-kill
Abort the capture process and return to the previous state.
@end table

@kindex k c @r{(Agenda)}
You can also call @code{org-capture} in a special way from the agenda,
using the @kbd{k c} key combination.  With this access, any
timestamps inserted by the selected capture template defaults to the
date at point in the agenda, rather than to the current date.

To find the locations of the last stored capture, use @code{org-capture}
with prefix commands:

@table @asis
@item @kbd{C-u M-x org-capture}
Visit the target location of a capture template.  You get to select
the template in the usual way.

@item @kbd{C-u C-u M-x org-capture}
Visit the last stored capture item in its buffer.
@end table

@vindex org-capture-bookmark
@vindex org-capture-last-stored
You can also jump to the bookmark @code{org-capture-last-stored}, which is
automatically created unless you set @code{org-capture-bookmark} to @code{nil}.

To insert the capture at point in an Org buffer, call @code{org-capture}
with a @kbd{C-0} prefix argument.

@node Capture templates
@subsection Capture templates

@cindex templates, for Capture

You can use templates for different types of capture items, and for
different target locations.  The easiest way to create such templates
is through the customize interface.

@table @asis
@item @kbd{C}
@kindex C @r{(Capture menu}
@vindex org-capture-templates
Customize the variable @code{org-capture-templates}.
@end table

Before we give the formal description of template definitions, let's
look at an example.  Say you would like to use one template to create
general TODO entries, and you want to put these entries under the
heading @samp{Tasks} in your file @samp{~/org/gtd.org}.  Also, a date tree in
the file @samp{journal.org} should capture journal entries.  A possible
configuration would look like:

@lisp
(setq org-capture-templates
      '(("t" "Todo" entry (file+headline "~/org/gtd.org" "Tasks")
         "* TODO %?\n  %i\n  %a")
        ("j" "Journal" entry (file+datetree "~/org/journal.org")
         "* %?\nEntered on %U\n  %i\n  %a")))
@end lisp

If you then press @kbd{t} from the capture menu, Org will prepare
the template for you like this:

@example
* TODO
  [[file:LINK TO WHERE YOU INITIATED CAPTURE]]
@end example

@noindent
During expansion of the template, @samp{%a} has been replaced by a link to
the location from where you called the capture command.  This can be
extremely useful for deriving tasks from emails, for example.  You
fill in the task definition, press @kbd{C-c C-c} and Org returns
you to the same place where you started the capture process.

To define special keys to capture to a particular template without
going through the interactive template selection, you can create your
key binding like this:

@lisp
(define-key global-map "\C-cx"
  (lambda () (interactive) (org-capture nil "x")))
@end lisp

@menu
* Template elements::            What is needed for a complete template entry.
* Template expansion::           Filling in information about time and context.
* Templates in contexts::        Only show a template in a specific context.
@end menu

@node Template elements
@subsubsection Template elements

Now lets look at the elements of a template definition.  Each entry in
@code{org-capture-templates} is a list with the following items:

@table @asis
@item keys
The keys that selects the template, as a string, characters only,
for example @samp{"a"}, for a template to be selected with a single key,
or @samp{"bt"} for selection with two keys.  When using several keys,
keys using the same prefix key must be sequential in the list and
preceded by a 2-element entry explaining the prefix key, for
example:

@lisp
("b" "Templates for marking stuff to buy")
@end lisp

If you do not define a template for the @kbd{C} key, this key
opens the Customize buffer for this complex variable.

@item description
A short string describing the template, shown during selection.

@item type
The type of entry, a symbol.  Valid values are:

@table @asis
@item @code{entry}
An Org mode node, with a headline.  Will be filed as the child of
the target entry or as a top-level entry.  The target file should
be an Org file.

@item @code{item}
A plain list item, placed in the first plain list at the target
location.  Again the target file should be an Org file.

@item @code{checkitem}
A checkbox item.  This only differs from the plain list item by
the default template.

@item @code{table-line}
A new line in the first table at the target location.  Where
exactly the line will be inserted depends on the properties
@code{:prepend} and @code{:table-line-pos} (see below).

@item @code{plain}
Text to be inserted as it is.
@end table

@item target
@vindex org-default-notes-file
@vindex org-directory
Specification of where the captured item should be placed.  In Org
files, targets usually define a node.  Entries will become children
of this node.  Other types will be added to the table or list in the
body of this node.  Most target specifications contain a file name.
If that file name is the empty string, it defaults to
@code{org-default-notes-file}.  A file can also be given as a variable or
as a function called with no argument.  When an absolute path is not
specified for a target, it is taken as relative to @code{org-directory}.

Valid values are:

@table @asis
@item @samp{(file "path/to/file")}
Text will be placed at the beginning or end of that file.

@item @samp{(id "id of existing org entry")}
Filing as child of this entry, or in the body of the entry.

@item @samp{(file+headline "filename" "node headline")}
Fast configuration if the target heading is unique in the file.

@item @samp{(file+olp "filename" "Level 1 heading" "Level 2" ...)}
For non-unique headings, the full path is safer.

@item @samp{(file+regexp "filename" "regexp to find location")}
Use a regular expression to position point.

@item @samp{(file+olp+datetree "filename" [ "Level 1 heading" ...])}
This target@footnote{Org used to offer four different targets for date/week tree
capture.  Now, Org automatically translates these to use
@code{file+olp+datetree}, applying the @code{:time-prompt} and @code{:tree-type}
properties.  Please rewrite your date/week-tree targets using
@code{file+olp+datetree} since the older targets are now deprecated.} creates a heading in a date tree@footnote{A date tree is an outline structure with years on the highest
level, months or ISO weeks as sublevels and then dates on the lowest
level.  Tags are allowed in the tree structure.} for
today's date.  If the optional outline path is given, the tree
will be built under the node it is pointing to, instead of at top
level.  Check out the @code{:time-prompt} and @code{:tree-type} properties
below for additional options.

@item @samp{(file+function "filename" function-finding-location)}
A function to find the right location in the file.

@item @samp{(clock)}
File to the entry that is currently being clocked.

@item @samp{(function function-finding-location)}
Most general way: write your own function which both visits the
file and moves point to the right location.
@end table

@item template
The template for creating the capture item.  If you leave this
empty, an appropriate default template will be used.  Otherwise this
is a string with escape codes, which will be replaced depending on
time and context of the capture call.  The string with escapes may
be loaded from a template file, using the special syntax @samp{(file
  "template filename")}.  See below for more details.

@item properties
The rest of the entry is a property list of additional options.
Recognized properties are:

@table @asis
@item @code{:prepend}
Normally new captured information will be appended at the target
location (last child, last table line, last list item, @dots{}).
Setting this property changes that.

@item @code{:immediate-finish}
When set, do not offer to edit the information, just file it away
immediately.  This makes sense if the template only needs
information that can be added automatically.

@item @code{:empty-lines}
Set this to the number of lines to insert before and after the new
item.  Default 0, and the only other common value is 1.

@item @code{:clock-in}
Start the clock in this item.

@item @code{:clock-keep}
Keep the clock running when filing the captured entry.

@item @code{:clock-resume}
If starting the capture interrupted a clock, restart that clock
when finished with the capture.  Note that @code{:clock-keep} has
precedence over @code{:clock-resume}.  When setting both to non-@code{nil},
the current clock will run and the previous one will not be
resumed.

@item @code{:time-prompt}
Prompt for a date/time to be used for date/week trees and when
filling the template.  Without this property, capture uses the
current date and time.  Even if this property has not been set,
you can force the same behavior by calling @code{org-capture} with
a @kbd{C-1} prefix argument.

@item @code{:tree-type}
When @code{week}, make a week tree instead of the month tree, i.e.,
place the headings for each day under a heading with the current
ISO week.

@item @code{:unnarrowed}
Do not narrow the target buffer, simply show the full buffer.
Default is to narrow it so that you only see the new material.

@item @code{:table-line-pos}
Specification of the location in the table where the new line
should be inserted.  It should be a string like @samp{II-3} meaning
that the new line should become the third line before the second
horizontal separator line.

@item @code{:kill-buffer}
If the target file was not yet visited when capture was invoked,
kill the buffer again after capture is completed.

@item @code{:no-save}
Do not save the target file after finishing the capture.
@end table
@end table

@node Template expansion
@subsubsection Template expansion

In the template itself, special ``%-escapes''@footnote{If you need one of these sequences literally, escape the @samp{%}
with a backslash.} allow dynamic
insertion of content.  The templates are expanded in the order given
here:

@table @asis
@item @samp{%[FILE]}
Insert the contents of the file given by @var{FILE}.

@item @samp{%(EXP)}
Evaluate Elisp expression @var{EXP} and replace it with the
result.  The @var{EXP} form must return a string.  Only
placeholders pre-existing within the template, or introduced with
@samp{%[file]}, are expanded this way.  Since this happens after
expanding non-interactive ``%-escapes'', those can be used to fill the
expression.

@item @samp{%<FORMAT>}
The result of format-time-string on the @var{FORMAT}
specification.

@item @samp{%t}
Timestamp, date only.

@item @samp{%T}
Timestamp, with date and time.

@item @samp{%u}, @samp{%U}
Like @samp{%t}, @samp{%T} above, but inactive timestamps.

@item @samp{%i}
Initial content, the region when capture is called while the region
is active.  If there is text before @samp{%i} on the same line, such as
indentation, and @samp{%i} is not inside a @samp{%(exp)} form, that prefix is
added before every line in the inserted text.

@item @samp{%a}
Annotation, normally the link created with @code{org-store-link}.

@item @samp{%A}
Like @samp{%a}, but prompt for the description part.

@item @samp{%l}
Like @samp{%a}, but only insert the literal link.

@item @samp{%c}
Current kill ring head.

@item @samp{%x}
Content of the X clipboard.

@item @samp{%k}
Title of the currently clocked task.

@item @samp{%K}
Link to the currently clocked task.

@item @samp{%n}
User name (taken from @code{user-full-name}).

@item @samp{%f}
File visited by current buffer when org-capture was called.

@item @samp{%F}
Full path of the file or directory visited by current buffer.

@item @samp{%:keyword}
Specific information for certain link types, see below.

@item @samp{%^g}
Prompt for tags, with completion on tags in target file.

@item @samp{%^G}
Prompt for tags, with completion all tags in all agenda files.

@item @samp{%^t}
Like @samp{%t}, but prompt for date.  Similarly @samp{%^T}, @samp{%^u}, @samp{%^U}.  You
may define a prompt like @samp{%^@{Birthday@}t}.

@item @samp{%^C}
Interactive selection of which kill or clip to use.

@item @samp{%^L}
Like @samp{%^C}, but insert as link.

@item @samp{%^@{PROP@}p}
Prompt the user for a value for property @var{PROP}.

@item @samp{%^@{PROMPT@}}
Prompt the user for a string and replace this sequence with it.  You
may specify a default value and a completion table with
@samp{%^@{prompt|default|completion2|completion3...@}}.  The arrow keys
access a prompt-specific history.

@item @samp{%\N}
Insert the text entered at the @var{N}th @samp{%^@{PROMPT@}}, where
@var{N} is a number, starting from 1.

@item @samp{%?}
After completing the template, position point here.
@end table

@vindex org-store-link-props
For specific link types, the following keywords are defined@footnote{If you define your own link types (see @ref{Adding Hyperlink Types}), any property you store with @code{org-store-link-props} can be
accessed in capture templates in a similar way.}:

@vindex org-link-from-user-regexp
@multitable {aaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@headitem Link type
@tab Available keywords
@item bbdb
@tab @samp{%:name}, @samp{%:company}
@item irc
@tab @samp{%:server}, @samp{%:port}, @samp{%:nick}
@item mh, rmail
@tab @samp{%:type}, @samp{%:subject}, @samp{%:message-id}
@item 
@tab @samp{%:from}, @samp{%:fromname}, @samp{%:fromaddress}
@item 
@tab @samp{%:to}, @samp{%:toname}, @samp{%:toaddress}
@item 
@tab @samp{%:date} (message date header field)
@item 
@tab @samp{%:date-timestamp} (date as active timestamp)
@item 
@tab @samp{%:date-timestamp-inactive} (date as inactive timestamp)
@item 
@tab @samp{%:fromto} (either ``to NAME'' or ``from NAME'')@footnote{This is always the other, not the user.  See the variable
@code{org-link-from-user-regexp}.}
@item gnus
@tab @samp{%:group}, for messages also all email fields
@item w3, w3m
@tab @samp{%:url}
@item info
@tab @samp{%:file}, @samp{%:node}
@item calendar
@tab @samp{%:date}
@item org-protocol
@tab @samp{%:link}, @samp{%:description}, @samp{%:annotation}
@end multitable

@node Templates in contexts
@subsubsection Templates in contexts

@vindex org-capture-templates-contexts
To control whether a capture template should be accessible from
a specific context, you can customize
@code{org-capture-templates-contexts}.  Let's say, for example, that you
have a capture template ``p'' for storing Gnus emails containing
patches.  Then you would configure this option like this:

@lisp
(setq org-capture-templates-contexts
      '(("p" (in-mode . "message-mode"))))
@end lisp

You can also tell that the command key @kbd{p} should refer to
another template.  In that case, add this command key like this:

@lisp
(setq org-capture-templates-contexts
      '(("p" "q" (in-mode . "message-mode"))))
@end lisp

See the docstring of the variable for more information.

@node Attachments
@section Attachments

@cindex attachments

It is often useful to associate reference material with an outline
node.  Small chunks of plain text can simply be stored in the subtree
of a project.  Hyperlinks (see @ref{Hyperlinks}) can establish associations
with files that live elsewhere on your computer or in the cloud, like
emails or source code files belonging to a project.

Another method is @emph{attachments}, which are files located in a
directory belonging to an outline node.  Org uses directories either
named by a unique ID of each entry, or by a @samp{DIR} property.

@menu
* Attachment defaults and dispatcher:: How to access attachment commands
* Attachment options::           Configuring the attachment system
* Attachment links::             Hyperlink access to attachments
* Automatic version-control with Git:: Everything safely stored away
* Attach from Dired::            Using dired to select an attachment
@end menu

@node Attachment defaults and dispatcher
@subsection Attachment defaults and dispatcher

By default, org-attach will use ID properties when adding attachments
to outline nodes.  This makes working with attachments fully
automated.  There is no decision needed for folder-name or location.
ID-based directories are by default located in the @samp{data/} directory,
which lives in the same directory where your Org file lives@footnote{If you move entries or Org files from one directory to
another, you may want to configure @code{org-attach-id-dir} to contain
an absolute path.}.
For more control over the setup, see @ref{Attachment options}.

When attachments are made using @code{org-attach} a default tag @samp{ATTACH} is
added to the node that gets the attachments.

The following commands deal with attachments:

@table @asis
@item @kbd{C-c C-a} (@code{org-attach})
@kindex C-c C-a
@findex org-attach
The dispatcher for commands related to the attachment system.  After
these keys, a list of commands is displayed and you must press an
additional key to select a command:

@table @asis
@item @kbd{a} (@code{org-attach-attach})
@kindex C-c C-a a
@findex org-attach-attach
@vindex org-attach-method
Select a file and move it into the task's attachment directory.
The file is copied, moved, or linked, depending on
@code{org-attach-method}.  Note that hard links are not supported on
all systems.

@item @kbd{c}/@kbd{m}/@kbd{l}
@kindex C-c C-a c
@kindex C-c C-a m
@kindex C-c C-a l
Attach a file using the copy/move/link method.  Note that hard
links are not supported on all systems.

@item @kbd{b} (@code{org-attach-buffer})
@kindex C-c C-a b
@findex org-attach-buffer
Select a buffer and save it as a file in the task's attachment
directory.

@item @kbd{n} (@code{org-attach-new})
@kindex C-c C-a n
@findex org-attach-new
Create a new attachment as an Emacs buffer.

@item @kbd{z} (@code{org-attach-sync})
@kindex C-c C-a z
@findex org-attach-sync
Synchronize the current task with its attachment directory, in
case you added attachments yourself.

@item @kbd{o} (@code{org-attach-open})
@kindex C-c C-a o
@findex org-attach-open
@vindex org-file-apps
Open current task's attachment.  If there is more than one, prompt
for a file name first.  Opening follows the rules set by
@code{org-file-apps}.  For more details, see the information on
following hyperlinks (see @ref{Handling Links}).

@item @kbd{O} (@code{org-attach-open-in-emacs})
@kindex C-c C-a O
@findex org-attach-open-in-emacs
Also open the attachment, but force opening the file in Emacs.

@item @kbd{f} (@code{org-attach-reveal})
@kindex C-c C-a f
@findex org-attach-reveal
Open the current task's attachment directory.

@item @kbd{F} (@code{org-attach-reveal-in-emacs})
@kindex C-c C-a F
@findex org-attach-reveal-in-emacs
Also open the directory, but force using Dired in Emacs.

@item @kbd{d} (@code{org-attach-delete-one})
@kindex C-c C-a d
Select and delete a single attachment.

@item @kbd{D} (@code{org-attach-delete-all})
@kindex C-c C-a D
Delete all of a task's attachments.  A safer way is to open the
directory in Dired and delete from there.

@item @kbd{s} (@code{org-attach-set-directory})
@kindex C-c C-a s
@cindex @samp{DIR}, property
Set a specific directory as the entry's attachment directory.
This works by putting the directory path into the @samp{DIR}
property.

@item @kbd{S} (@code{org-attach-unset-directory})
@kindex C-c C-a S
@cindex @samp{DIR}, property
Remove the attachment directory.  This command removes the @samp{DIR}
property and asks the user to either move content inside that
folder, if an @samp{ID} property is set, delete the content, or to
leave the attachment directory as is but no longer attached to the
outline node.
@end table
@end table

@node Attachment options
@subsection Attachment options

There are a couple of options for attachments that are worth
mentioning.

@table @asis
@item @code{org-attach-id-dir}
@vindex org-attach-id-dir
The directory where attachments are stored when @samp{ID} is used as
method.

@item @code{org-attach-dir-relative}
@vindex org-attach-dir-relative
When setting the @samp{DIR} property on a node using @kbd{C-c C-a s}
(@code{org-attach-set-directory}), absolute links are entered by default.
This option changes that to relative links.

@item @code{org-attach-use-inheritance}
@vindex org-attach-use-inheritance
By default folders attached to an outline node are inherited from
parents according to @code{org-use-property-inheritance}.  If one instead
want to set inheritance specifically for org-attach that can be done
using @code{org-attach-use-inheritance}.  Inheriting documents through
the node hierarchy makes a lot of sense in most cases. Especially
since the introduction of @ref{Attachment links}.  The following example
shows one use case for attachment inheritance:

@example
* Chapter A ...
  :PROPERTIES:
  :DIR: Chapter A/
  :END:
** Introduction
Some text

#+NAME: Image 1
[[Attachment:image 1.jpg]]
@end example

Without inheritance one would not be able to resolve the link to
image @samp{1.jpg}, since the link is inside a sub-heading to @samp{Chapter
  A}.

Inheritance works the same way for both @samp{ID} and @samp{DIR} property.  If
both properties are defined on the same headline then @samp{DIR} takes
precedance.  This is also true if inheritance is enabled.  If @samp{DIR}
is inherited from a parent node in the outline, that property still
takes precedence over an @samp{ID} property defined on the node itself.

@item @code{org-attach-method}
@vindex org-attach-method
When attaching files using the dispatcher @kbd{C-c C-a} it
defaults to copying files.  The behaviour can be changed by
customizing @code{org-attach-method}.  Options are Copy, Move/Rename,
Hard link or Symbolic link.

@item @code{org-attach-preferred-new-method}
@vindex org-attach-preferred-new-method
This customization lets you choose the default way to attach to
nodes without existing @samp{ID} and @samp{DIR} property.  It defaults to @code{id}
but can also be set to @code{dir}, @code{ask} or @code{nil}.

@item @code{org-attach-archive-delete}
@vindex org-attach-archive-delete
Configure this to determine if attachments should be deleted or not
when a subtree that has attachments is archived.

@item @code{org-attach-auto-tag}
@vindex org-attach-auto-tag
When attaching files to a heading it will be assigned a tag
according to what is set here.

@item @code{org-attach-id-to-path-function-list}
@vindex org-attach-id-to-path-function-list
When @samp{ID} is used for attachments, the ID is parsed into a part of a
directory-path.  See @code{org-attach-id-uuid-folder-format} for the
default function.  Define a new one and add it as first element in
@code{org-attach-id-to-path-function-list} if you want the folder
structure in any other way.  All functions in this list will be
tried when resolving existing ID's into paths, to maintain backward
compatibility with existing folders in your system.

@item @code{org-attach-expert}
@vindex org-attach-expert
Do not show the splash buffer with the attach dispatcher when
@code{org-attach-expert} is set to non-@code{nil}.
@end table

See customization group @samp{Org Attach} if you want to change the
default settings.

@node Attachment links
@subsection Attachment links

Attached files and folders can be referenced using attachment links.
This makes it easy to refer to the material added to an outline node.
Especially if it was attached using the unique ID of the entry!

@example
* TODO Some task
  :PROPERTIES:
  :ID:       95d50008-c12e-479f-a4f2-cc0238205319
  :END:
See attached document for more information: [[attachment:info.org]]
@end example

See @ref{External Links} for more information about these links.

@node Automatic version-control with Git
@subsection Automatic version-control with Git

If the directory attached to an outline node is a Git repository, Org
can be configured to automatically commit changes to that repository
when it sees them.

To make Org mode take care of versioning of attachments for you, add
the following to your Emacs config:

@lisp
(require 'org-attach-git)
@end lisp

@node Attach from Dired
@subsection Attach from Dired

@cindex attach from Dired
@findex org-attach-dired-to-subtree
It is possible to attach files to a subtree from a Dired buffer.  To
use this feature, have one window in Dired mode containing the file(s)
to be attached and another window with point in the subtree that shall
get the attachments.  In the Dired window, with point on a file,
@kbd{M-x org-attach-dired-to-subtree} attaches the file to the
subtree using the attachment method set by variable
@code{org-attach-method}.  When files are marked in the Dired window then
all marked files get attached.

Add the following lines to the Emacs init file to have @kbd{C-c C-x a} attach files in Dired buffers.

@lisp
(add-hook 'dired-mode-hook
          (lambda ()
            (define-key dired-mode-map
              (kbd "C-c C-x a")
              #'org-attach-dired-to-subtree)))
@end lisp

The following code shows how to bind the previous command with
a specific attachment method.

@lisp
(add-hook 'dired-mode-hook
          (lambda ()
            (define-key dired-mode-map (kbd "C-c C-x c")
              (lambda ()
                (interactive)
                (let ((org-attach-method 'cp))
                  (call-interactively #'org-attach-dired-to-subtree))))))
@end lisp

@node RSS Feeds
@section RSS Feeds

@cindex RSS feeds
@cindex Atom feeds

Org can add and change entries based on information found in RSS feeds
and Atom feeds.  You could use this to make a task out of each new
podcast in a podcast feed.  Or you could use a phone-based
note-creating service on the web to import tasks into Org.  To access
feeds, configure the variable @code{org-feed-alist}.  The docstring of this
variable has detailed information.  With the following

@lisp
(setq org-feed-alist
      '(("Slashdot"
         "http://rss.slashdot.org/Slashdot/slashdot"
         "~/txt/org/feeds.org" "Slashdot Entries")))
@end lisp

@noindent
new items from the feed provided by @samp{rss.slashdot.org} result in new
entries in the file @samp{~/org/feeds.org} under the heading @samp{Slashdot
Entries}, whenever the following command is used:

@table @asis
@item @kbd{C-c C-x g} (@code{org-feed-update-all})
@kindex C-c C-x g
Collect items from the feeds configured in @code{org-feed-alist} and act
upon them.

@item @kbd{C-c C-x G} (@code{org-feed-goto-inbox})
@kindex C-c C-x G
Prompt for a feed name and go to the inbox configured for this feed.
@end table

Under the same headline, Org creates a drawer @samp{FEEDSTATUS} in which it
stores information about the status of items in the feed, to avoid
adding the same item several times.

For more information, including how to read atom feeds, see
@samp{org-feed.el} and the docstring of @code{org-feed-alist}.

@node Agenda Views
@chapter Agenda Views

@cindex agenda views

Due to the way Org works, TODO items, time-stamped items, and tagged
headlines can be scattered throughout a file or even a number of
files.  To get an overview of open action items, or of events that are
important for a particular date, this information must be collected,
sorted and displayed in an organized way.

Org can select items based on various criteria and display them in
a separate buffer.  Six different view types are provided:

@itemize
@item
an @emph{agenda} that is like a calendar and shows information for
specific dates,

@item
a @emph{TODO list} that covers all unfinished action items,

@item
a @emph{match view}, showings headlines based on the tags, properties,
and TODO state associated with them,

@item
a @emph{text search view} that shows all entries from multiple files that
contain specified keywords,

@item
a @emph{stuck projects view} showing projects that currently do not move
along, and

@item
@emph{custom views} that are special searches and combinations of
different views.
@end itemize

The extracted information is displayed in a special @emph{agenda buffer}.
This buffer is read-only, but provides commands to visit the
corresponding locations in the original Org files, and even to edit
these files remotely.

@vindex org-agenda-skip-comment-trees
@vindex org-agenda-skip-archived-trees
@cindex commented entries, in agenda views
@cindex archived entries, in agenda views
By default, the report ignores commented (see @ref{Comment Lines}) and
archived (see @ref{Internal archiving}) entries.  You can override this by
setting @code{org-agenda-skip-comment-trees} and
@code{org-agenda-skip-archived-trees} to @code{nil}.

@vindex org-agenda-window-setup
@vindex org-agenda-restore-windows-after-quit
Two variables control how the agenda buffer is displayed and whether
the window configuration is restored when the agenda exits:
@code{org-agenda-window-setup} and @code{org-agenda-restore-windows-after-quit}.

@menu
* Agenda Files::                 Files being searched for agenda information.
* Agenda Dispatcher::            Keyboard access to agenda views.
* Built-in Agenda Views::        What is available out of the box?
* Presentation and Sorting::     How agenda items are prepared for display.
* Agenda Commands::              Remote editing of Org trees.
* Custom Agenda Views::          Defining special searches and views.
* Exporting Agenda Views::       Writing a view to a file.
* Agenda Column View::           Using column view for collected entries.
@end menu

@node Agenda Files
@section Agenda Files

@cindex agenda files
@cindex files for agenda

@vindex org-agenda-files
The information to be shown is normally collected from all @emph{agenda
files}, the files listed in the variable @code{org-agenda-files}@footnote{If the value of that variable is not a list, but a single file
name, then the list of agenda files in maintained in that external
file.}.
If a directory is part of this list, all files with the extension
@samp{.org} in this directory are part of the list.

Thus, even if you only work with a single Org file, that file should
be put into the list@footnote{When using the dispatcher, pressing @kbd{<} before
selecting a command actually limits the command to the current file,
and ignores @code{org-agenda-files} until the next dispatcher command.}.  You can customize @code{org-agenda-files},
but the easiest way to maintain it is through the following commands

@table @asis
@item @kbd{C-c [} (@code{org-agenda-file-to-front})
@kindex C-c [
@findex org-agenda-file-to-front
@cindex files, adding to agenda list
Add current file to the list of agenda files.  The file is added to
the front of the list.  If it was already in the list, it is moved
to the front.  With a prefix argument, file is added/moved to the
end.

@item @kbd{C-c ]} (@code{org-remove-file})
@kindex C-c ]
@findex org-remove-file
Remove current file from the list of agenda files.

@item @kbd{C-'}
@itemx @kbd{C-,} (@code{org-cycle-agenda-files})
@kindex C-'
@kindex C-,
@findex org-cycle-agenda-files
@cindex cycling, of agenda files
Cycle through agenda file list, visiting one file after the other.

@item @kbd{M-x org-switchb}
@findex org-switchb
Command to use an Iswitchb-like interface to switch to and between
Org buffers.
@end table

@noindent
The Org menu contains the current list of files and can be used to
visit any of them.

If you would like to focus the agenda temporarily on a file not in
this list, or on just one file in the list, or even on only a subtree
in a file, then this can be done in different ways.  For a single
agenda command, you may press @kbd{<} once or several times in
the dispatcher (see @ref{Agenda Dispatcher}).  To restrict the agenda
scope for an extended period, use the following commands:

@table @asis
@item @kbd{C-c C-x <} (@code{org-agenda-set-restriction-lock})
@kindex C-c C-x <
@findex org-agenda-set-restriction-lock
Restrict the agenda to the current subtree.  If there already is
a restriction at point, remove it.  When called with a universal
prefix argument or with point before the first headline in a file,
set the agenda scope to the entire file.  This restriction remains
in effect until removed with @kbd{C-c C-x >}, or by typing
either @kbd{<} or @kbd{>} in the agenda dispatcher.  If
there is a window displaying an agenda view, the new restriction
takes effect immediately.

@item @kbd{C-c C-x >} (@code{org-agenda-remove-restriction-lock})
@kindex C-c C-x >
@findex org-agenda-remove-restriction-lock
Remove the restriction created by @kbd{C-c C-x <}.
@end table

When working with Speedbar, you can use the following commands in the
Speedbar frame:

@table @asis
@item @kbd{<} (@code{org-speedbar-set-agenda-restriction})
@findex org-speedbar-set-agenda-restriction
Restrict the agenda to the item---either an Org file or a subtree in
such a file---at point in the Speedbar frame.  If agenda is already
restricted there, remove the restriction.  If there is a window
displaying an agenda view, the new restriction takes effect
immediately.

@item @kbd{>} (@code{org-agenda-remove-restriction-lock})
@findex org-agenda-remove-restriction-lock
Remove the restriction.
@end table

@node Agenda Dispatcher
@section The Agenda Dispatcher

@cindex agenda dispatcher
@cindex dispatching agenda commands

The views are created through a dispatcher, accessible with @kbd{M-x org-agenda}, or, better, bound to a global key (see @ref{Activation}).
It displays a menu from which an additional letter is required to
execute a command.  The dispatcher offers the following default
commands:

@table @asis
@item @kbd{a}
Create the calendar-like agenda (see @ref{Weekly/daily agenda}).

@item @kbd{t}
@itemx @kbd{T}
Create a list of all TODO items (see @ref{Global TODO list}).

@item @kbd{m}
@itemx @kbd{M}
Create a list of headlines matching a given expression (see
@ref{Matching tags and properties}).

@item @kbd{s}
@kindex s @r{(Agenda dispatcher)}
Create a list of entries selected by a boolean expression of
keywords and/or regular expressions that must or must not occur in
the entry.

@item @kbd{/}
@kindex / @r{(Agenda dispatcher)}
@vindex org-agenda-text-search-extra-files
Search for a regular expression in all agenda files and additionally
in the files listed in @code{org-agenda-text-search-extra-files}.  This
uses the Emacs command @code{multi-occur}.  A prefix argument can be used
to specify the number of context lines for each match, default is
@enumerate
@item
@end enumerate

@item @kbd{#}
@itemx @kbd{!}
Create a list of stuck projects (see @ref{Stuck projects}).

@item @kbd{<}
@kindex < @r{(Agenda dispatcher)}
Restrict an agenda command to the current buffer@footnote{For backward compatibility, you can also press @kbd{1} to
restrict to the current buffer.}.  If
narrowing is in effect restrict to the narrowed part of the buffer.
After pressing @kbd{<}, you still need to press the character
selecting the command.

@item @kbd{< <}
@kindex < < @r{(Agenda dispatcher)}
If there is an active region, restrict the following agenda command
to the region.  Otherwise, restrict it to the current
subtree@footnote{For backward compatibility, you can also press @kbd{0} to
restrict to the current region/subtree.}.  After pressing @kbd{< <}, you still need to
press the character selecting the command.

@item @kbd{*}
@kindex * @r{(Agenda dispatcher)}
@vindex org-agenda-sticky
@findex org-toggle-sticky-agenda
Toggle sticky agenda views.  By default, Org maintains only a single
agenda buffer and rebuilds it each time you change the view, to make
sure everything is always up to date.  If you switch between views
often and the build time bothers you, you can turn on sticky agenda
buffers (make this the default by customizing the variable
@code{org-agenda-sticky}).  With sticky agendas, the dispatcher only
switches to the selected view, you need to update it by hand with
@kbd{r} or @kbd{g}.  You can toggle sticky agenda view any
time with @code{org-toggle-sticky-agenda}.
@end table

You can also define custom commands that are accessible through the
dispatcher, just like the default commands.  This includes the
possibility to create extended agenda buffers that contain several
blocks together, for example the weekly agenda, the global TODO list
and a number of special tags matches.  See @ref{Custom Agenda Views}.

@node Built-in Agenda Views
@section The Built-in Agenda Views

In this section we describe the built-in views.

@menu
* Weekly/daily agenda::          The calendar page with current tasks.
* Global TODO list::             All unfinished action items.
* Matching tags and properties:: Structured information with fine-tuned search.
* Search view::                  Find entries by searching for text.
* Stuck projects::               Find projects you need to review.
@end menu

@node Weekly/daily agenda
@subsection Weekly/daily agenda

@cindex agenda
@cindex weekly agenda
@cindex daily agenda

The purpose of the weekly/daily @emph{agenda} is to act like a page of
a paper agenda, showing all the tasks for the current week or day.

@table @asis
@item @kbd{M-x org-agenda a} (@code{org-agenda-list})
@kindex a @r{(Agenda dispatcher)}
@findex org-agenda-list
@cindex org-agenda, command
Compile an agenda for the current week from a list of Org files.
The agenda shows the entries for each day.  With a numeric prefix
argument@footnote{For backward compatibility, the universal prefix argument
@kbd{C-u} causes all TODO entries to be listed before the agenda.
This feature is deprecated, use the dedicated TODO list, or a block
agenda instead (see @ref{Block agenda}).}---like @kbd{C-u 2 1 M-x org-agenda a}---you may
set the number of days to be displayed.
@end table

@vindex org-agenda-span
@vindex org-agenda-start-day
@vindex org-agenda-start-on-weekday
The default number of days displayed in the agenda is set by the
variable @code{org-agenda-span}.  This variable can be set to any number of
days you want to see by default in the agenda, or to a span name, such
a @code{day}, @code{week}, @code{month} or @code{year}.  For weekly agendas, the default
is to start on the previous Monday (see
@code{org-agenda-start-on-weekday}).  You can also set the start date using
a date shift: @samp{(setq org-agenda-start-day "+10d")} starts the agenda
ten days from today in the future.

Remote editing from the agenda buffer means, for example, that you can
change the dates of deadlines and appointments from the agenda buffer.
The commands available in the Agenda buffer are listed in @ref{Agenda Commands}.

@anchor{Calendar/Diary integration}
@subsubheading Calendar/Diary integration

@cindex calendar integration
@cindex diary integration

Emacs contains the calendar and diary by Edward@tie{}M@.@tie{}Reingold.  The
calendar displays a three-month calendar with holidays from different
countries and cultures.  The diary allows you to keep track of
anniversaries, lunar phases, sunrise/set, recurrent appointments
(weekly, monthly) and more.  In this way, it is quite complementary to
Org.  It can be very useful to combine output from Org with the diary.

In order to include entries from the Emacs diary into Org mode's
agenda, you only need to customize the variable

@lisp
(setq org-agenda-include-diary t)
@end lisp

@noindent
After that, everything happens automatically.  All diary entries
including holidays, anniversaries, etc., are included in the agenda
buffer created by Org mode.  @kbd{@key{SPC}}, @kbd{@key{TAB}}, and
@kbd{@key{RET}} can be used from the agenda buffer to jump to the diary
file in order to edit existing diary entries.  The @kbd{i}
command to insert new entries for the current date works in the agenda
buffer, as well as the commands @kbd{S}, @kbd{M}, and
@kbd{C} to display Sunrise/Sunset times, show lunar phases and to
convert to other calendars, respectively.  @kbd{c} can be used to
switch back and forth between calendar and agenda.

If you are using the diary only for expression entries and holidays,
it is faster to not use the above setting, but instead to copy or even
move the entries into an Org file.  Org mode evaluates diary-style
expression entries, and does it faster because there is no overhead
for first creating the diary display.  Note that the expression
entries must start at the left margin, no whitespace is allowed before
them, as seen in the following segment of an Org file:@footnote{The variable @code{org-anniversary} used in the example is just
like @code{diary-anniversary}, but the argument order is always according
to ISO and therefore independent of the value of
@code{calendar-date-style}.}

@example
* Holidays
  :PROPERTIES:
  :CATEGORY: Holiday
  :END:
%%(org-calendar-holiday)   ; special function for holiday names

* Birthdays
  :PROPERTIES:
  :CATEGORY: Ann
  :END:
%%(org-anniversary 1956  5 14) Arthur Dent is %d years old
%%(org-anniversary 1869 10  2) Mahatma Gandhi would be %d years old
@end example

@anchor{Anniversaries from BBDB}
@subsubheading Anniversaries from BBDB

@cindex BBDB, anniversaries
@cindex anniversaries, from BBDB

@findex org-bbdb-anniversaries
If you are using the Insidious Big Brother Database to store your
contacts, you very likely prefer to store anniversaries in BBDB rather
than in a separate Org or diary file.  Org supports this and can show
BBDB anniversaries as part of the agenda.  All you need to do is to
add the following to one of your agenda files:

@example
* Anniversaries
  :PROPERTIES:
  :CATEGORY: Anniv
  :END:
%%(org-bbdb-anniversaries)
@end example

You can then go ahead and define anniversaries for a BBDB record.
Basically, you need a field named @samp{anniversary} for the BBDB record
which contains the date in the format @samp{YYYY-MM-DD} or @samp{MM-DD},
followed by a space and the class of the anniversary (@samp{birthday},
@samp{wedding}, or a format string).  If you omit the class, it defaults to
@samp{birthday}.  Here are a few examples, the header for the file
@samp{ol-bbdb.el} contains more detailed information.

@example
1973-06-22
06-22
1955-08-02 wedding
2008-04-14 %s released version 6.01 of Org mode, %d years ago
@end example

After a change to BBDB, or for the first agenda display during an
Emacs session, the agenda display suffers a short delay as Org updates
its hash with anniversaries.  However, from then on things will be
very fast, much faster in fact than a long list of
@samp{%%(diary-anniversary)} entries in an Org or Diary file.

@findex org-bbdb-anniversaries-future
If you would like to see upcoming anniversaries with a bit of
forewarning, you can use the following instead:

@example
* Anniversaries
  :PROPERTIES:
  :CATEGORY: Anniv
  :END:
%%(org-bbdb-anniversaries-future 3)
@end example

That will give you three days' warning: on the anniversary date itself
and the two days prior.  The argument is optional: if omitted, it
defaults to 7.

@anchor{Appointment reminders}
@subsubheading Appointment reminders

@cindex @file{appt.el}
@cindex appointment reminders
@cindex appointment
@cindex reminders

@cindex APPT_WARNTIME, keyword
Org can interact with Emacs appointments notification facility.  To
add the appointments of your agenda files, use the command
@code{org-agenda-to-appt}.  This command lets you filter through the list
of your appointments and add only those belonging to a specific
category or matching a regular expression.  It also reads
a @samp{APPT_WARNTIME} property which overrides the value of
@code{appt-message-warning-time} for this appointment.  See the docstring
for details.

@node Global TODO list
@subsection The global TODO list

@cindex global TODO list
@cindex TODO list, global

The global TODO list contains all unfinished TODO items formatted and
collected into a single place.

@table @asis
@item @kbd{M-x org-agenda t} (@code{org-todo-list})
@kindex t @r{(Agenda dispatcher)}
@findex org-todo-list
Show the global TODO list.  This collects the TODO items from all
agenda files (see @ref{Agenda Views}) into a single buffer.  By default,
this lists items with a state the is not a DONE state.  The buffer
is in Agenda mode, so there are commands to examine and manipulate
the TODO entries directly from that buffer (see @ref{Agenda Commands}).

@item @kbd{M-x org-agenda T} (@code{org-todo-list})
@kindex T @r{(Agenda dispatcher)}
@findex org-todo-list
@cindex TODO keyword matching
@vindex org-todo-keywords
Like the above, but allows selection of a specific TODO keyword.
You can also do this by specifying a prefix argument to
@kbd{t}.  You are prompted for a keyword, and you may also
specify several keywords by separating them with @samp{|} as the boolean
OR operator.  With a numeric prefix, the Nth keyword in
@code{org-todo-keywords} is selected.

@kindex r
The @kbd{r} key in the agenda buffer regenerates it, and you
can give a prefix argument to this command to change the selected
TODO keyword, for example @kbd{3 r}.  If you often need
a search for a specific keyword, define a custom command for it (see
@ref{Agenda Dispatcher}).

Matching specific TODO keywords can also be done as part of a tags
search (see @ref{Tag Searches}).
@end table

Remote editing of TODO items means that you can change the state of
a TODO entry with a single key press.  The commands available in the
TODO list are described in @ref{Agenda Commands}.

@cindex sublevels, inclusion into TODO list
Normally the global TODO list simply shows all headlines with TODO
keywords.  This list can become very long.  There are two ways to keep
it more compact:

@itemize
@item
@vindex org-agenda-todo-ignore-scheduled
@vindex org-agenda-todo-ignore-deadlines
@vindex org-agenda-todo-ignore-timestamp
@vindex org-agenda-todo-ignore-with-date
Some people view a TODO item that has been @emph{scheduled} for execution
or have a @emph{deadline} (see @ref{Timestamps}) as no longer @emph{open}.
Configure the variables @code{org-agenda-todo-ignore-scheduled} to
exclude some or all scheduled items from the global TODO list,
@code{org-agenda-todo-ignore-deadlines} to exclude some or all items with
a deadline set, @code{org-agenda-todo-ignore-timestamp} to exclude some
or all items with an active timestamp other than a DEADLINE or
a SCHEDULED timestamp and/or @code{org-agenda-todo-ignore-with-date} to
exclude items with at least one active timestamp.

@item
@vindex org-agenda-todo-list-sublevels
TODO items may have sublevels to break up the task into subtasks.
In such cases it may be enough to list only the highest level TODO
headline and omit the sublevels from the global list.  Configure the
variable @code{org-agenda-todo-list-sublevels} to get this behavior.
@end itemize

@node Matching tags and properties
@subsection Matching tags and properties

@cindex matching, of tags
@cindex matching, of properties
@cindex tags view
@cindex match view

If headlines in the agenda files are marked with @emph{tags} (see @ref{Tags}),
or have properties (see @ref{Properties and Columns}), you can select
headlines based on this metadata and collect them into an agenda
buffer.  The match syntax described here also applies when creating
sparse trees with @kbd{C-c / m}.

@table @asis
@item @kbd{M-x org-agenda m} (@code{org-tags-view})
@kindex m @r{(Agenda dispatcher)}
@findex org-tags-view
Produce a list of all headlines that match a given set of tags.  The
command prompts for a selection criterion, which is a boolean logic
expression with tags, like @samp{+work+urgent-withboss} or @samp{work|home}
(see @ref{Tags}).  If you often need a specific search, define a custom
command for it (see @ref{Agenda Dispatcher}).

@item @kbd{M-x org-agenda M} (@code{org-tags-view})
@kindex M @r{(Agenda dispatcher)}
@findex org-tags-view
@vindex org-tags-match-list-sublevels
@vindex org-agenda-tags-todo-honor-ignore-options
Like @kbd{m}, but only select headlines that are also TODO
items and force checking subitems (see the variable
@code{org-tags-match-list-sublevels}).  To exclude scheduled/deadline
items, see the variable @code{org-agenda-tags-todo-honor-ignore-options}.
Matching specific TODO keywords together with a tags match is also
possible, see @ref{Tag Searches}.
@end table

The commands available in the tags list are described in @ref{Agenda Commands}.

@cindex boolean logic, for agenda searches
A search string can use Boolean operators @samp{&} for AND and @samp{|} for OR@.
@samp{&} binds more strongly than @samp{|}.  Parentheses are currently not
implemented.  Each element in the search is either a tag, a regular
expression matching tags, or an expression like @samp{PROPERTY OPERATOR
VALUE} with a comparison operator, accessing a property value.  Each
element may be preceded by @samp{-} to select against it, and @samp{+} is
syntactic sugar for positive selection.  The AND operator @samp{&} is
optional when @samp{+} or @samp{-} is present.  Here are some examples, using
only tags.

@table @asis
@item @samp{+work-boss}
Select headlines tagged @samp{work}, but discard those also tagged
@samp{boss}.

@item @samp{work|laptop}
Selects lines tagged @samp{work} or @samp{laptop}.

@item @samp{work|laptop+night}
Like before, but require the @samp{laptop} lines to be tagged also
@samp{night}.
@end table

@cindex regular expressions, with tags search
Instead of a tag, you may also specify a regular expression enclosed
in curly braces.  For example, @samp{work+@{^boss.*@}} matches headlines that
contain the tag @samp{:work:} and any tag @emph{starting} with @samp{boss}.

@cindex group tags, as regular expressions
Group tags (see @ref{Tag Hierarchy}) are expanded as regular expressions.
E.g., if @samp{work} is a group tag for the group @samp{:work:lab:conf:}, then
searching for @samp{work} also searches for @samp{@{\(?:work\|lab\|conf\)@}} and
searching for @samp{-work} searches for all headlines but those with one of
the tags in the group (i.e., @samp{-@{\(?:work\|lab\|conf\)@}}).

@cindex TODO keyword matching, with tags search
@cindex level, for tags/property match
@cindex category, for tags/property match
@vindex org-odd-levels-only
You may also test for properties (see @ref{Properties and Columns}) at the
same time as matching tags.  The properties may be real properties, or
special properties that represent other metadata (see @ref{Special Properties}).  For example, the property @samp{TODO} represents the TODO
keyword of the entry.  Or, the property @samp{LEVEL} represents the level
of an entry.  So searching @samp{+LEVEL=3+boss-TODO​="DONE"} lists all level
three headlines that have the tag @samp{boss} and are @emph{not} marked with the
TODO keyword @samp{DONE}.  In buffers with @code{org-odd-levels-only} set,
@samp{LEVEL} does not count the number of stars, but @samp{LEVEL=2} corresponds
to 3 stars etc.

Here are more examples:

@table @asis
@item @samp{work+TODO​="WAITING"}
Select @samp{work}-tagged TODO lines with the specific TODO keyword
@samp{WAITING}.

@item @samp{work+TODO​="WAITING"|home+TODO​="WAITING"}
Waiting tasks both at work and at home.
@end table

When matching properties, a number of different operators can be used
to test the value of a property.  Here is a complex example:

@example
+work-boss+PRIORITY="A"+Coffee="unlimited"+Effort<2
         +With=@{Sarah|Denny@}+SCHEDULED>="<2008-10-11>"
@end example

@noindent
The type of comparison depends on how the comparison value is written:

@itemize
@item
If the comparison value is a plain number, a numerical comparison is
done, and the allowed operators are @samp{<}, @samp{=}, @samp{>}, @samp{<=}, @samp{>=}, and
@samp{<>}.

@item
If the comparison value is enclosed in double-quotes, a string
comparison is done, and the same operators are allowed.

@item
If the comparison value is enclosed in double-quotes @emph{and} angular
brackets (like @samp{DEADLINE<​="<2008-12-24 18:30>"}), both values are
assumed to be date/time specifications in the standard Org way, and
the comparison is done accordingly.  Valid values also include
@samp{"<now>"} for now (including time), @samp{"<today>"}, and @samp{"<tomorrow>"}
for these days at 0:00 hours, i.e., without a time specification.
You can also use strings like @samp{"<+5d>"} or @samp{"<-2m>"} with units @samp{d},
@samp{w}, @samp{m}, and @samp{y} for day, week, month, and year, respectively.

@item
If the comparison value is enclosed in curly braces, a regexp match
is performed, with @samp{=} meaning that the regexp matches the property
value, and @samp{<>} meaning that it does not match.
@end itemize

So the search string in the example finds entries tagged @samp{work} but
not @samp{boss}, which also have a priority value @samp{A}, a @samp{Coffee} property
with the value @samp{unlimited}, an @samp{EFFORT} property that is numerically
smaller than 2, a @samp{With} property that is matched by the regular
expression @samp{Sarah|Denny}, and that are scheduled on or after October
11, 2008.

You can configure Org mode to use property inheritance during
a search, but beware that this can slow down searches considerably.
See @ref{Property Inheritance}, for details.

For backward compatibility, and also for typing speed, there is also
a different way to test TODO states in a search.  For this, terminate
the tags/property part of the search string (which may include several
terms connected with @samp{|}) with a @samp{/} and then specify a Boolean
expression just for TODO keywords.  The syntax is then similar to that
for tags, but should be applied with care: for example, a positive
selection on several TODO keywords cannot meaningfully be combined
with boolean AND@.  However, @emph{negative selection} combined with AND can
be meaningful.  To make sure that only lines are checked that actually
have any TODO keyword (resulting in a speed-up), use @kbd{M-x org-agenda M}, or equivalently start the TODO part after the slash
with @samp{!}.  Using @kbd{M-x org-agenda M} or @samp{/!} does not match
TODO keywords in a DONE state.  Examples:

@table @asis
@item @samp{work/WAITING}
Same as @samp{work+TODO​="WAITING"}.

@item @samp{work/!-WAITING-NEXT}
Select @samp{work}-tagged TODO lines that are neither @samp{WAITING} nor
@samp{NEXT}.

@item @samp{work/!+WAITING|+NEXT}
Select @samp{work}-tagged TODO lines that are either @samp{WAITING} or @samp{NEXT}.
@end table

@node Search view
@subsection Search view

@cindex search view
@cindex text search
@cindex searching, for text

This agenda view is a general text search facility for Org mode
entries.  It is particularly useful to find notes.

@table @asis
@item @kbd{M-x org-agenda s} (@code{org-search-view})
@kindex s @r{(Agenda dispatcher)}
@findex org-search-view
This is a special search that lets you select entries by matching
a substring or specific words using a boolean logic.
@end table

For example, the search string @samp{computer equipment} matches entries
that contain @samp{computer equipment} as a substring, even if the two
words are separated by more space or a line break.

Search view can also search for specific keywords in the entry, using
Boolean logic.  The search string @samp{+computer
+wifi -ethernet -@{8\.11[bg]@}} matches note entries that contain the
keywords @samp{computer} and @samp{wifi}, but not the keyword @samp{ethernet}, and
which are also not matched by the regular expression @samp{8\.11[bg]},
meaning to exclude both @samp{8.11b} and @samp{8.11g}.  The first @samp{+} is
necessary to turn on boolean search, other @samp{+} characters are
optional.  For more details, see the docstring of the command
@code{org-search-view}.

You can incrementally and conveniently adjust a boolean search from
the agenda search view with the following keys

@multitable @columnfractions 0.1 0.6
@item @kbd{[}
@tab Add a positive search word
@item @kbd{]}
@tab Add a negative search word
@item @kbd{@{}
@tab Add a positive regular expression
@item @kbd{@}}
@tab Add a negative regular expression
@end multitable

@vindex org-agenda-text-search-extra-files
Note that in addition to the agenda files, this command also searches
the files listed in @code{org-agenda-text-search-extra-files}.

@node Stuck projects
@subsection Stuck projects

@pindex GTD, Getting Things Done

If you are following a system like David Allen's GTD to organize your
work, one of the ``duties'' you have is a regular review to make sure
that all projects move along.  A @emph{stuck} project is a project that has
no defined next actions, so it never shows up in the TODO lists Org
mode produces.  During the review, you need to identify such projects
and define next actions for them.

@table @asis
@item @kbd{M-x org-agenda #} (@code{org-agenda-list-stuck-projects})
@kindex # @r{(Agenda dispatcher)}
@findex org-agenda-list-stuck-projects
List projects that are stuck.

@item @kbd{M-x org-agenda !}
@kindex ! @r{(Agenda dispatcher)}
@vindex org-stuck-projects
Customize the variable @code{org-stuck-projects} to define what a stuck
project is and how to find it.
@end table

You almost certainly need to configure this view before it works for
you.  The built-in default assumes that all your projects are level-2
headlines, and that a project is not stuck if it has at least one
entry marked with a TODO keyword @samp{TODO} or @samp{NEXT} or @samp{NEXTACTION}.

Let's assume that you, in your own way of using Org mode, identify
projects with a tag @samp{:PROJECT:}, and that you use a TODO keyword
@samp{MAYBE} to indicate a project that should not be considered yet.
Let's further assume that the TODO keyword @samp{DONE} marks finished
projects, and that @samp{NEXT} and @samp{TODO} indicate next actions.  The tag
@samp{:@@shop:} indicates shopping and is a next action even without the
NEXT tag.  Finally, if the project contains the special word @samp{IGNORE}
anywhere, it should not be listed either.  In this case you would
start by identifying eligible projects with a tags/TODO match (see
@ref{Tag Searches}) @samp{+PROJECT/-MAYBE-DONE}, and then check for @samp{TODO},
@samp{NEXT}, @samp{@@shop}, and @samp{IGNORE} in the subtree to identify projects that
are not stuck.  The correct customization for this is:

@lisp
(setq org-stuck-projects
      '("+PROJECT/-MAYBE-DONE" ("NEXT" "TODO") ("@@shop")
        "\\<IGNORE\\>"))
@end lisp

Note that if a project is identified as non-stuck, the subtree of this
entry is searched for stuck projects.

@node Presentation and Sorting
@section Presentation and Sorting

@cindex presentation, of agenda items

@vindex org-agenda-prefix-format
@vindex org-agenda-tags-column
Before displaying items in an agenda view, Org mode visually prepares
the items and sorts them.  Each item occupies a single line.  The line
starts with a @emph{prefix} that contains the @emph{category} (see @ref{Categories})
of the item and other important information.  You can customize in
which column tags are displayed through @code{org-agenda-tags-column}.  You
can also customize the prefix using the option
@code{org-agenda-prefix-format}.  This prefix is followed by a cleaned-up
version of the outline headline associated with the item.

@menu
* Categories::                   Not all tasks are equal.
* Time-of-day specifications::   How the agenda knows the time.
* Sorting of agenda items::      The order of things.
* Filtering/limiting agenda items:: Dynamically narrow the agenda.
@end menu

@node Categories
@subsection Categories

@cindex category
@cindex @samp{CATEGORY}, keyword

The category is a broad label assigned to each agenda item.  By
default, the category is simply derived from the file name, but you
can also specify it with a special line in the buffer, like
this:

@example
#+CATEGORY: Thesis
@end example


@cindex @samp{CATEGORY}, property
If you would like to have a special category for a single entry or
a (sub)tree, give the entry a @samp{CATEGORY} property with the special
category you want to apply as the value.

@vindex org-agenda-category-icon-alist
The display in the agenda buffer looks best if the category is not
longer than 10 characters.  You can set up icons for category by
customizing the @code{org-agenda-category-icon-alist} variable.

@node Time-of-day specifications
@subsection Time-of-day specifications

@cindex time-of-day specification

Org mode checks each agenda item for a time-of-day specification.  The
time can be part of the timestamp that triggered inclusion into the
agenda, for example

@example
<2005-05-10 Tue 19:00>
@end example


@noindent
Time ranges can be specified with two timestamps:

@example
<2005-05-10 Tue 20:30>--<2005-05-10 Tue 22:15>
@end example


@vindex org-agenda-search-headline-for-time
In the headline of the entry itself, a time(range)---like @samp{12:45} or
a @samp{8:30-1pm}---may also appear as plain text@footnote{You can, however, disable this by setting
@code{org-agenda-search-headline-for-time} variable to a @code{nil} value.}.

If the agenda integrates the Emacs diary (see @ref{Weekly/daily agenda}),
time specifications in diary entries are recognized as well.

For agenda display, Org mode extracts the time and displays it in
a standard 24 hour format as part of the prefix.  The example times in
the previous paragraphs would end up in the agenda like this:

@example
 8:30-13:00 Arthur Dent lies in front of the bulldozer
12:45...... Ford Prefect arrives and takes Arthur to the pub
19:00...... The Vogon reads his poem
20:30-22:15 Marvin escorts the Hitchhikers to the bridge
@end example

@cindex time grid
If the agenda is in single-day mode, or for the display of today, the
timed entries are embedded in a time grid, like

@example
 8:00...... ------------------
 8:30-13:00 Arthur Dent lies in front of the bulldozer
10:00...... ------------------
12:00...... ------------------
12:45...... Ford Prefect arrives and takes Arthur to the pub
14:00...... ------------------
16:00...... ------------------
18:00...... ------------------
19:00...... The Vogon reads his poem
20:00...... ------------------
20:30-22:15 Marvin escorts the Hitchhikers to the bridge
@end example

@vindex org-agenda-use-time-grid
@vindex org-agenda-time-grid
The time grid can be turned on and off with the variable
@code{org-agenda-use-time-grid}, and can be configured with
@code{org-agenda-time-grid}.

@node Sorting of agenda items
@subsection Sorting of agenda items

@cindex sorting, of agenda items
@cindex priorities, of agenda items

Before being inserted into a view, the items are sorted.  How this is
done depends on the type of view.

@itemize
@item
@vindex org-agenda-files
For the daily/weekly agenda, the items for each day are sorted.  The
default order is to first collect all items containing an explicit
time-of-day specification.  These entries are shown at the beginning
of the list, as a @emph{schedule} for the day.  After that, items remain
grouped in categories, in the sequence given by @code{org-agenda-files}.
Within each category, items are sorted by priority (see
@ref{Priorities}), which is composed of the base priority (2000 for
priority @samp{A}, 1000 for @samp{B}, and 0 for @samp{C}), plus additional
increments for overdue scheduled or deadline items.

@item
For the TODO list, items remain in the order of categories, but
within each category, sorting takes place according to priority (see
@ref{Priorities}).  The priority used for sorting derives from the
priority cookie, with additions depending on how close an item is to
its due or scheduled date.

@item
For tags matches, items are not sorted at all, but just appear in
the sequence in which they are found in the agenda files.
@end itemize

@vindex org-agenda-sorting-strategy
Sorting can be customized using the variable
@code{org-agenda-sorting-strategy}, and may also include criteria based on
the estimated effort of an entry (see @ref{Effort Estimates}).

@node Filtering/limiting agenda items
@subsection Filtering/limiting agenda items

@vindex org-agenda-category-filter-preset
@vindex org-agenda-tag-filter-preset
@vindex org-agenda-effort-filter-preset
@vindex org-agenda-regexp-filter-preset
Agenda built-in or custom commands are statically defined.  Agenda
filters and limits allow to flexibly narrow down the list of agenda
entries.

@emph{Filters} only change the visibility of items, are very fast and are
mostly used interactively@footnote{Custom agenda commands can preset a filter by binding one of
the variables @code{org-agenda-tag-filter-preset},
@code{org-agenda-category-filter-preset}, @code{org-agenda-effort-filter-preset}
or @code{org-agenda-regexp-filter-preset} as an option.  This filter is
then applied to the view and persists as a basic filter through
refreshes and more secondary filtering.  The filter is a global
property of the entire agenda view---in a block agenda, you should
only set this in the global options section, not in the section of an
individual block.}. You can switch quickly between
different filters without having to recreate the agenda.  @emph{Limits} on
the other hand take effect before the agenda buffer is populated, so
they are mostly useful when defined as local variables within custom
agenda commands.

@anchor{Filtering in the agenda}
@subsubheading Filtering in the agenda

@cindex agenda filtering
@cindex filtering entries, in agenda
@cindex tag filtering, in agenda
@cindex category filtering, in agenda
@cindex top headline filtering, in agenda
@cindex effort filtering, in agenda
@cindex query editing, in agenda

The general filtering command is @code{org-agenda-filter}, bound to
@kbd{/}.  Before we introduce it, we describe commands for
individual filter types.  All filtering commands handle prefix
arguments in the same way:  A single @kbd{C-u} prefix negates the
filter, so it removes lines selected by the filter.  A double prefix
adds the new filter condition to the one(s) already in place, so
filter elements are accumulated.

@table @asis
@item @kbd{\} (@code{org-agenda-filter-by-tag})
@findex org-agenda-filter-by-tag
Filter the agenda view with respect to a tag.  You are prompted for
a tag selection letter; @kbd{@key{SPC}} means any tag at all.
Pressing @kbd{@key{TAB}} at that prompt offers completion to select a
tag, including any tags that do not have a selection character.  The
command then hides all entries that do not contain or inherit this
tag.  Pressing @kbd{+} or @kbd{-} at the prompt switches
between filtering for and against the next tag.  To clear the
filter, press @kbd{\} twice (once to call the command again,
and once at the prompt).

@item @kbd{<} (@code{org-agenda-filter-by-category})
@findex org-agenda-filter-by-category
Filter by category of the line at point, and show only entries with
this category.  When called with a prefix argument, hide all entries
with the category at point.  To clear the filter, call this command
again by pressing @kbd{<}.

@item @kbd{=} (@code{org-agenda-filter-by-regexp})
@findex org-agenda-filter-by-regexp
Filter the agenda view by a regular expression: only show agenda
entries matching the regular expression the user entered. To clear
the filter, call the command again by pressing @kbd{=}.

@item @kbd{_} (@code{org-agenda-filter-by-effort})
@findex org-agenda-filter-by-effort
Filter the agenda view with respect to effort estimates, so select
tasks that take the right amount of time.  You first need to set up
a list of efforts globally, for example

@lisp
(setq org-global-properties
      '(("Effort_ALL". "0 0:10 0:30 1:00 2:00 3:00 4:00")))
@end lisp

@vindex org-sort-agenda-noeffort-is-high
You can then filter for an effort by first typing an operator, one
of @kbd{<}, @kbd{>} and @kbd{=}, and then the
one-digit index of an effort estimate in your array of allowed
values, where @kbd{0} means the 10th value.  The filter then
restricts to entries with effort smaller-or-equal, equal, or
larger-or-equal than the selected value.  For application of the
operator, entries without a defined effort are treated according to
the value of @code{org-sort-agenda-noeffort-is-high}.  To clear the
filter, press @kbd{_} twice (once to call the command again,
and once at the first prompt).

@item @kbd{^} (@code{org-agenda-filter-by-top-headline})
@findex org-agenda-filter-by-top-headline
Filter the current agenda view and only display items that fall
under the same top-level headline as the current entry.  To clear
the filter, call this command again by pressing @kbd{^}.

@item @kbd{/} (@code{org-agenda-filter})
@findex org-agenda-filter
This is the unified interface to four of the five filter methods
described above.  At the prompt, specify different filter elements
in a single string, with full completion support.  For example,

@example
+work-John+<0:10-/plot/
@end example

selects entries with category `work' and effort estimates below 10
minutes, and deselects entries with tag `John' or matching the
regexp `plot'.  `+' can be left out if that does not lead to
ambiguities.  The sequence of elements is arbitrary.  The filter
syntax assumes that there is no overlap between categories and tags
(tags will take priority).  If you reply to the prompt with the
empty string, all filtering is removed.  If a filter is specified,
it replaces all current filters.  But if you call the command with a
double prefix argument, or if you add an additional `+'
(e.g. `++work') to the front of the string, the new filter elements
are added to the active ones.  A single prefix argument applies the
entire filter in a negative sense.

@item @kbd{|} (@code{org-agenda-filter-remove-all})
Remove all filters in the current agenda view.
@end table

@anchor{Computed tag filtering}
@subsubheading Computed tag filtering

@vindex org-agenda-auto-exclude-function
If the variable @code{org-agenda-auto-exclude-function} is set to a
user-defined function, that function can select tags that should be
used as a tag filter when requested.  The function will be called with
lower-case versions of all tags represented in the current view. The
function should the return @samp{"-tag"} if the filter should remove
entries with that tag, @samp{"+tag"} if only entries with this tag should
be kept, or @samp{nil} if that tag is irrelevant. For example, let's say
you use a @samp{Net} tag to identify tasks which need network access, an
@samp{Errand} tag for errands in town, and a @samp{Call} tag for making phone
calls.  You could auto-exclude these tags based on the availability of
the Internet, and outside of business hours, with something like this:

@lisp
(defun org-my-auto-exclude-fn (tag)
  (if (cond
       ((string= tag "net")
        (/= 0 (call-process "/sbin/ping" nil nil nil
                            "-c1" "-q" "-t1" "mail.gnu.org")))
       ((member tag '("errand" "call"))
        (let ((hr (nth 2 (decode-time))))
          (or (< hr 8) (> hr 21)))))
      (concat "-" tag)))

(setq org-agenda-auto-exclude-function 'org-my-auto-exclude-fn)
@end lisp

You can apply this self-adapting filter by using a double prefix
argument to @code{org-agenda-filter}, i.e. press @kbd{C-u C-u /}, or
by pressing @kbd{@key{RET}} in @code{org-agenda-filter-by-tag}.

@anchor{Setting limits for the agenda}
@subsubheading Setting limits for the agenda

@cindex limits, in agenda

Here is a list of options that you can set, either globally, or
locally in your custom agenda views (see @ref{Custom Agenda Views}).

@table @asis
@item @code{org-agenda-max-entries}
@vindex org-agenda-max-entries
Limit the number of entries.

@item @code{org-agenda-max-effort}
@vindex org-agenda-max-effort
Limit the duration of accumulated efforts (as minutes).

@item @code{org-agenda-max-todos}
@vindex org-agenda-max-todos
Limit the number of entries with TODO keywords.

@item @code{org-agenda-max-tags}
@vindex org-agenda-max-tags
Limit the number of tagged entries.
@end table

When set to a positive integer, each option excludes entries from
other categories: for example, @samp{(setq org-agenda-max-effort 100)}
limits the agenda to 100 minutes of effort and exclude any entry that
has no effort property.  If you want to include entries with no effort
property, use a negative value for @code{org-agenda-max-effort}.  One
useful setup is to use @code{org-agenda-max-entries} locally in a custom
command.  For example, this custom command displays the next five
entries with a @samp{NEXT} TODO keyword.

@lisp
(setq org-agenda-custom-commands
      '(("n" todo "NEXT"
         ((org-agenda-max-entries 5)))))
@end lisp

Once you mark one of these five entry as DONE, rebuilding the agenda
will again the next five entries again, including the first entry that
was excluded so far.

You can also dynamically set temporary limits, which are lost when
rebuilding the agenda:

@table @asis
@item @kbd{~} (@code{org-agenda-limit-interactively})
@findex org-agenda-limit-interactively
This prompts for the type of limit to apply and its value.
@end table

@node Agenda Commands
@section Commands in the Agenda Buffer

@cindex commands, in agenda buffer

Entries in the agenda buffer are linked back to the Org file or diary
file where they originate.  You are not allowed to edit the agenda
buffer itself, but commands are provided to show and jump to the
original entry location, and to edit the Org files ``remotely'' from the
agenda buffer.  In this way, all information is stored only once,
removing the risk that your agenda and note files may diverge.

Some commands can be executed with mouse clicks on agenda lines.  For
the other commands, point needs to be in the desired line.

@anchor{Motion (1)}
@subheading Motion

@cindex motion commands in agenda

@table @asis
@item @kbd{n} (@code{org-agenda-next-line})
@kindex n
@findex org-agenda-next-line
Next line (same as @kbd{@key{DOWN}} and @kbd{C-n}).

@item @kbd{p} (@code{org-agenda-previous-line})
@kindex p
@findex org-agenda-previous-line
Previous line (same as @kbd{@key{UP}} and @kbd{C-p}).
@end table

@anchor{View/Go to Org file}
@subheading View/Go to Org file

@cindex view file commands in agenda

@table @asis
@item @kbd{@key{SPC}} or @kbd{mouse-3} (@code{org-agenda-show-and-scroll-up})
@kindex SPC
@kindex mouse-3
@findex org-agenda-show-and-scroll-up
Display the original location of the item in another window.
With a prefix argument, make sure that drawers stay folded.

@item @kbd{L} (@code{org-agenda-recenter})
@findex org-agenda-recenter
Display original location and recenter that window.

@item @kbd{@key{TAB}} or @kbd{mouse-2} (@code{org-agenda-goto})
@kindex TAB
@kindex mouse-2
@findex org-agenda-goto
Go to the original location of the item in another window.

@item @kbd{@key{RET}} (@code{org-agenda-switch-to})
@kindex RET
@findex org-agenda-switch-to
Go to the original location of the item and delete other windows.

@item @kbd{F} (@code{org-agenda-follow-mode})
@kindex F
@findex org-agenda-follow-mode
@vindex org-agenda-start-with-follow-mode
Toggle Follow mode.  In Follow mode, as you move point through the
agenda buffer, the other window always shows the corresponding
location in the Org file.  The initial setting for this mode in new
agenda buffers can be set with the variable
@code{org-agenda-start-with-follow-mode}.

@item @kbd{C-c C-x b} (@code{org-agenda-tree-to-indirect-buffer})
@kindex C-c C-x b
@findex org-agenda-tree-to-indirect-buffer
Display the entire subtree of the current item in an indirect
buffer.  With a numeric prefix argument N, go up to level N and then
take that tree.  If N is negative, go up that many levels.  With
a @kbd{C-u} prefix, do not remove the previously used indirect
buffer.

@item @kbd{C-c C-o} (@code{org-agenda-open-link})
@kindex C-c C-o
@findex org-agenda-open-link
Follow a link in the entry.  This offers a selection of any links in
the text belonging to the referenced Org node.  If there is only one
link, follow it without a selection prompt.
@end table

@anchor{Change display}
@subheading Change display

@cindex change agenda display
@cindex display changing, in agenda

@table @asis
@item @kbd{A}
@kindex A
Interactively select another agenda view and append it to the
current view.

@item @kbd{o}
@kindex o
Delete other windows.

@item @kbd{v d} or short @kbd{d} (@code{org-agenda-day-view})
@kindex v d
@kindex d
@findex org-agenda-day-view
Switch to day view.  When switching to day view, this setting
becomes the default for subsequent agenda refreshes.  A numeric
prefix argument may be used to jump directly to a specific day of
the year.  For example, @kbd{32 d} jumps to February 1st.  When
setting day view, a year may be encoded in the prefix argument as
well.  For example, @kbd{200712 d} jumps to January 12, 2007.
If such a year specification has only one or two digits, it is
expanded into one of the 30 next years or the last 69 years.

@item @kbd{v w} or short @kbd{w} (@code{org-agenda-week-view})
@kindex v w
@kindex w
@findex org-agenda-week-view
Switch to week view.  When switching week view, this setting becomes
the default for subsequent agenda refreshes.  A numeric prefix
argument may be used to jump directly to a specific day of the ISO
week.  For example @kbd{9 w} to ISO week number 9.  When
setting week view, a year may be encoded in the prefix argument as
well.  For example, @kbd{200712 w} jumps to week 12 in 2007.
If such a year specification has only one or two digits, it is
expanded into one of the 30 next years or the last 69 years.

@item @kbd{v m} (@code{org-agenda-month-view})
@kindex v m
@findex org-agenda-month-view
Switch to month view.  Because month views are slow to create, they
do not become the default for subsequent agenda refreshes.
A numeric prefix argument may be used to jump directly to a specific
day of the month.  When setting month view, a year may be encoded in
the prefix argument as well.  For example, @kbd{200712 m} jumps
to December, 2007.  If such a year specification has only one or two
digits, it is expanded into one of the 30 next years or the last 69
years.

@item @kbd{v y} (@code{org-agenda-year-view})
@kindex v y
@findex org-agenda-year-view
Switch to year view.  Because year views are slow to create, they do
not become the default for subsequent agenda refreshes.  A numeric
prefix argument may be used to jump directly to a specific day of
the year.

@item @kbd{v @key{SPC}} (@code{org-agenda-reset-view})
@kindex v SPC
@findex org-agenda-reset-view
@vindex org-agenda-span
Reset the current view to @code{org-agenda-span}.

@item @kbd{f} (@code{org-agenda-later})
@kindex f
@findex org-agenda-later
Go forward in time to display the span following the current one.
For example, if the display covers a week, switch to the following
week.  With a prefix argument, repeat that many times.

@item @kbd{b} (@code{org-agenda-earlier})
@kindex b
@findex org-agenda-earlier
Go backward in time to display earlier dates.

@item @kbd{.} (@code{org-agenda-goto-today})
@kindex .
@findex org-agenda-goto-today
Go to today.

@item @kbd{j} (@code{org-agenda-goto-date})
@kindex j
@findex org-agenda-goto-date
Prompt for a date and go there.

@item @kbd{J} (@code{org-agenda-clock-goto})
@kindex J
@findex org-agenda-clock-goto
Go to the currently clocked-in task @emph{in the agenda buffer}.

@item @kbd{D} (@code{org-agenda-toggle-diary})
@kindex D
@findex org-agenda-toggle-diary
Toggle the inclusion of diary entries.  See @ref{Weekly/daily agenda}.

@item @kbd{v l} or @kbd{v L} or short @kbd{l} (@code{org-agenda-log-mode})
@kindex v l
@kindex l
@kindex v L
@findex org-agenda-log-mode
@vindex org-log-done
@vindex org-agenda-log-mode-items
Toggle Logbook mode.  In Logbook mode, entries that were marked as
done while logging was on (see the variable @code{org-log-done}) are
shown in the agenda, as are entries that have been clocked on that
day.  You can configure the entry types that should be included in
log mode using the variable @code{org-agenda-log-mode-items}.  When
called with a @kbd{C-u} prefix argument, show all possible
logbook entries, including state changes.  When called with two
prefix arguments @kbd{C-u C-u}, show only logging information,
nothing else.  @kbd{v L} is equivalent to @kbd{C-u v l}.

@item @kbd{v [} or short @kbd{[} (@code{org-agenda-manipulate-query-add})
@kindex v [
@kindex [
@findex org-agenda-manipulate-query-add
Include inactive timestamps into the current view.  Only for
weekly/daily agenda.

@item @kbd{v a} (@code{org-agenda-archives-mode})
@kindex v a
@findex org-agenda-archives-mode
Toggle Archives mode.  In Archives mode, trees that are archived
(see @ref{Internal archiving}) are also scanned when producing the
agenda.  To exit archives mode, press @kbd{v a} again.

@item @kbd{v A}
@kindex v A
Toggle Archives mode.  Include all archive files as well.

@item @kbd{v R} or short @kbd{R} (@code{org-agenda-clockreport-mode})
@kindex v R
@kindex R
@findex org-agenda-clockreport-mode
@vindex org-agenda-start-with-clockreport-mode
@vindex org-clock-report-include-clocking-task
Toggle Clockreport mode.  In Clockreport mode, the daily/weekly
agenda always shows a table with the clocked times for the time span
and file scope covered by the current agenda view.  The initial
setting for this mode in new agenda buffers can be set with the
variable @code{org-agenda-start-with-clockreport-mode}.  By using
a prefix argument when toggling this mode (i.e., @kbd{C-u R}),
the clock table does not show contributions from entries that are
hidden by agenda filtering@footnote{Only tags filtering is respected here, effort filtering is
ignored.}.  See also the variable
@code{org-clock-report-include-clocking-task}.

@item @kbd{v c}
@kindex v c
@vindex org-agenda-clock-consistency-checks
Show overlapping clock entries, clocking gaps, and other clocking
problems in the current agenda range.  You can then visit clocking
lines and fix them manually.  See the variable
@code{org-agenda-clock-consistency-checks} for information on how to
customize the definition of what constituted a clocking problem.  To
return to normal agenda display, press @kbd{l} to exit Logbook
mode.

@item @kbd{v E} or short @kbd{E} (@code{org-agenda-entry-text-mode})
@kindex v E
@kindex E
@findex org-agenda-entry-text-mode
@vindex org-agenda-start-with-entry-text-mode
@vindex org-agenda-entry-text-maxlines
Toggle entry text mode.  In entry text mode, a number of lines from
the Org outline node referenced by an agenda line are displayed
below the line.  The maximum number of lines is given by the
variable @code{org-agenda-entry-text-maxlines}.  Calling this command
with a numeric prefix argument temporarily modifies that number to
the prefix value.

@item @kbd{G} (@code{org-agenda-toggle-time-grid})
@kindex G
@vindex org-agenda-use-time-grid
@vindex org-agenda-time-grid
Toggle the time grid on and off.  See also the variables
@code{org-agenda-use-time-grid} and @code{org-agenda-time-grid}.

@item @kbd{r} (@code{org-agenda-redo})
@itemx @kbd{g}
@kindex r
@kindex g
@findex org-agenda-redo
Recreate the agenda buffer, for example to reflect the changes after
modification of the timestamps of items with @kbd{S-@key{LEFT}} and
@kbd{S-@key{RIGHT}}.  When the buffer is the global TODO list,
a prefix argument is interpreted to create a selective list for
a specific TODO keyword.

@item @kbd{C-x C-s} or short @kbd{s} (@code{org-save-all-org-buffers})
@kindex C-x C-s
@findex org-save-all-org-buffers
@kindex s
Save all Org buffers in the current Emacs session, and also the
locations of IDs.

@item @kbd{C-c C-x C-c} (@code{org-agenda-columns})
@kindex C-c C-x C-c
@findex org-agenda-columns
@vindex org-columns-default-format
Invoke column view (see @ref{Column View}) in the agenda buffer.  The
column view format is taken from the entry at point, or, if there is
no entry at point, from the first entry in the agenda view.  So
whatever the format for that entry would be in the original buffer
(taken from a property, from a @samp{COLUMNS} keyword, or from the
default variable @code{org-columns-default-format}) is used in the
agenda.

@item @kbd{C-c C-x >} (@code{org-agenda-remove-restriction-lock})
@kindex C-c C-x >
@findex org-agenda-remove-restriction-lock
Remove the restriction lock on the agenda, if it is currently
restricted to a file or subtree (see @ref{Agenda Files}).

@item @kbd{M-@key{UP}} (@code{org-agenda-drag-line-backward})
@kindex M-UP
@findex org-agenda-drag-line-backward
Drag the line at point backward one line.  With a numeric prefix
argument, drag backward by that many lines.

Moving agenda lines does not persist after an agenda refresh and
does not modify the contributing Org files.

@item @kbd{M-@key{DOWN}} (@code{org-agenda-drag-line-forward})
@kindex M-DOWN
@findex org-agenda-drag-line-forward
Drag the line at point forward one line.  With a numeric prefix
argument, drag forward by that many lines.
@end table

@anchor{Remote editing}
@subheading Remote editing

@cindex remote editing, from agenda

@table @asis
@item @kbd{0--9}
Digit argument.

@item @kbd{C-_} (@code{org-agenda-undo})
@kindex C-_
@findex org-agenda-undo
@cindex undoing remote-editing events
@cindex remote editing, undo
Undo a change due to a remote editing command.  The change is undone
both in the agenda buffer and in the remote buffer.

@item @kbd{t} (@code{org-agenda-todo})
@kindex t
@findex org-agenda-todo
Change the TODO state of the item, both in the agenda and in the
original Org file. A prefix arg is passed through to the @code{org-todo}
command, so for example a @kbd{C-u} prefix are will trigger
taking a note to document the state change.

@item @kbd{C-S-@key{RIGHT}} (@code{org-agenda-todo-nextset})
@kindex C-S-RIGHT
@findex org-agenda-todo-nextset
Switch to the next set of TODO keywords.

@item @kbd{C-S-@key{LEFT}}, @code{org-agenda-todo-previousset}
@kindex C-S-LEFT
Switch to the previous set of TODO keywords.

@item @kbd{C-k} (@code{org-agenda-kill})
@kindex C-k
@findex org-agenda-kill
@vindex org-agenda-confirm-kill
Delete the current agenda item along with the entire subtree
belonging to it in the original Org file.  If the text to be deleted
remotely is longer than one line, the kill needs to be confirmed by
the user.  See variable @code{org-agenda-confirm-kill}.

@item @kbd{C-c C-w} (@code{org-agenda-refile})
@kindex C-c C-w
@findex org-agenda-refile
Refile the entry at point.

@item @kbd{C-c C-x C-a} or short @kbd{a} (@code{org-agenda-archive-default-with-confirmation})
@kindex C-c C-x C-a
@kindex a
@findex org-agenda-archive-default-with-confirmation
@vindex org-archive-default-command
Archive the subtree corresponding to the entry at point using the
default archiving command set in @code{org-archive-default-command}.
When using the @kbd{a} key, confirmation is required.

@item @kbd{C-c C-x a} (@code{org-agenda-toggle-archive-tag})
@kindex C-c C-x a
@findex org-agenda-toggle-archive-tag
Toggle the archive tag (see @ref{Internal archiving}) for the current
headline.

@item @kbd{C-c C-x A} (@code{org-agenda-archive-to-archive-sibling})
@kindex C-c C-x A
@findex org-agenda-archive-to-archive-sibling
Move the subtree corresponding to the current entry to its @emph{archive
sibling}.

@item @kbd{C-c C-x C-s} or short @kbd{$} (@code{org-agenda-archive})
@kindex C-c C-x C-s
@kindex $
@findex org-agenda-archive
Archive the subtree corresponding to the current headline.  This
means the entry is moved to the configured archive location, most
likely a different file.

@item @kbd{T} (@code{org-agenda-show-tags})
@kindex T
@findex org-agenda-show-tags
@vindex org-agenda-show-inherited-tags
Show all tags associated with the current item.  This is useful if
you have turned off @code{org-agenda-show-inherited-tags}, but still want
to see all tags of a headline occasionally.

@item @kbd{:} (@code{org-agenda-set-tags})
@kindex :
@findex org-agenda-set-tags
Set tags for the current headline.  If there is an active region in
the agenda, change a tag for all headings in the region.

@item @kbd{,} (@code{org-agenda-priority})
@kindex ,
@findex org-agenda-priority
Set the priority for the current item.  Org mode prompts for the
priority character.  If you reply with @kbd{@key{SPC}}, the priority
cookie is removed from the entry.

@item @kbd{P} (@code{org-agenda-show-priority})
@kindex P
@findex org-agenda-show-priority
Display weighted priority of current item.

@item @kbd{+} or @kbd{S-@key{UP}} (@code{org-agenda-priority-up})
@kindex +
@kindex S-UP
@findex org-agenda-priority-up
Increase the priority of the current item.  The priority is changed
in the original buffer, but the agenda is not resorted.  Use the
@kbd{r} key for this.

@item @kbd{-} or @kbd{S-@key{DOWN}} (@code{org-agenda-priority-down})
@kindex -
@kindex S-DOWN
@findex org-agenda-priority-down
Decrease the priority of the current item.

@item @kbd{C-c C-z} or short @kbd{z} (@code{org-agenda-add-note})
@kindex z
@kindex C-c C-z
@findex org-agenda-add-note
@vindex org-log-into-drawer
Add a note to the entry.  This note is recorded, and then filed to
the same location where state change notes are put.  Depending on
@code{org-log-into-drawer}, this may be inside a drawer.

@item @kbd{C-c C-a} (@code{org-attach})
@kindex C-c C-a
@findex org-attach
Dispatcher for all command related to attachments.

@item @kbd{C-c C-s} (@code{org-agenda-schedule})
@kindex C-c C-s
@findex org-agenda-schedule
Schedule this item.  With a prefix argument, remove the
scheduling timestamp

@item @kbd{C-c C-d} (@code{org-agenda-deadline})
@kindex C-c C-d
@findex org-agenda-deadline
Set a deadline for this item.  With a prefix argument, remove the
deadline.

@item @kbd{S-@key{RIGHT}} (@code{org-agenda-do-date-later})
@kindex S-RIGHT
@findex org-agenda-do-date-later
Change the timestamp associated with the current line by one day
into the future.  If the date is in the past, the first call to this
command moves it to today.  With a numeric prefix argument, change
it by that many days.  For example, @kbd{3 6 5 S-@key{RIGHT}} changes
it by a year.  With a @kbd{C-u} prefix, change the time by one
hour.  If you immediately repeat the command, it will continue to
change hours even without the prefix argument.  With a double
@kbd{C-u C-u} prefix, do the same for changing minutes.  The
stamp is changed in the original Org file, but the change is not
directly reflected in the agenda buffer.  Use @kbd{r} or
@kbd{g} to update the buffer.

@item @kbd{S-@key{LEFT}} (@code{org-agenda-do-date-earlier})
@kindex S-LEFT
@findex org-agenda-do-date-earlier
Change the timestamp associated with the current line by one day
into the past.

@item @kbd{>} (@code{org-agenda-date-prompt})
@kindex >
@findex org-agenda-date-prompt
Change the timestamp associated with the current line.  The key
@kbd{>} has been chosen, because it is the same as
@kbd{S-.}  on my keyboard.

@item @kbd{I} (@code{org-agenda-clock-in})
@kindex I
@findex org-agenda-clock-in
Start the clock on the current item.  If a clock is running already,
it is stopped first.

@item @kbd{O} (@code{org-agenda-clock-out})
@kindex O
@findex org-agenda-clock-out
Stop the previously started clock.

@item @kbd{X} (@code{org-agenda-clock-cancel})
@kindex X
@findex org-agenda-clock-cancel
Cancel the currently running clock.

@item @kbd{J} (@code{org-agenda-clock-goto})
@kindex J
@findex org-agenda-clock-goto
Jump to the running clock in another window.

@item @kbd{k} (@code{org-agenda-capture})
@kindex k
@findex org-agenda-capture
@cindex capturing, from agenda
@vindex org-capture-use-agenda-date
Like @code{org-capture}, but use the date at point as the default date
for the capture template.  See @code{org-capture-use-agenda-date} to make
this the default behavior of @code{org-capture}.
@end table

@anchor{Bulk remote editing selected entries}
@subheading Bulk remote editing selected entries

@cindex remote editing, bulk, from agenda
@vindex org-agenda-bulk-custom-functions

@table @asis
@item @kbd{m} (@code{org-agenda-bulk-mark})
@kindex m
@findex org-agenda-bulk-mark

Mark the entry at point for bulk action.  If there is an active
region in the agenda, mark the entries in the region.  With numeric
prefix argument, mark that many successive entries.

@item @kbd{*} (@code{org-agenda-bulk-mark-all})
@kindex *
@findex org-agenda-bulk-mark-all

Mark all visible agenda entries for bulk action.

@item @kbd{u} (@code{org-agenda-bulk-unmark})
@kindex u
@findex org-agenda-bulk-unmark

Unmark entry for bulk action.

@item @kbd{U} (@code{org-agenda-bulk-remove-all-marks})
@kindex U
@findex org-agenda-bulk-remove-all-marks

Unmark all marked entries for bulk action.

@item @kbd{M-m} (@code{org-agenda-bulk-toggle})
@kindex M-m
@findex org-agenda-bulk-toggle

Toggle mark of the entry at point for bulk action.

@item @kbd{M-*} (@code{org-agenda-bulk-toggle-all})
@kindex M-*
@findex org-agenda-bulk-toggle-all

Toggle mark of every entry for bulk action.

@item @kbd{%} (@code{org-agenda-bulk-mark-regexp})
@kindex %
@findex org-agenda-bulk-mark-regexp

Mark entries matching a regular expression for bulk action.

@item @kbd{B} (@code{org-agenda-bulk-action})
@kindex B
@findex org-agenda-bulk-action
@vindex org-agenda-bulk-persistent-marks

Bulk action: act on all marked entries in the agenda.  This prompts
for another key to select the action to be applied.  The prefix
argument to @kbd{B} is passed through to the @kbd{s} and
@kbd{d} commands, to bulk-remove these special timestamps.  By
default, marks are removed after the bulk.  If you want them to
persist, set @code{org-agenda-bulk-persistent-marks} to @code{t} or hit
@kbd{p} at the prompt.

@table @asis
@item @kbd{p}
Toggle persistent marks.

@item @kbd{$}
Archive all selected entries.

@item @kbd{A}
Archive entries by moving them to their respective archive
siblings.

@item @kbd{t}
Change TODO state.  This prompts for a single TODO keyword and
changes the state of all selected entries, bypassing blocking and
suppressing logging notes---but not timestamps.

@item @kbd{+}
Add a tag to all selected entries.

@item @kbd{-}
Remove a tag from all selected entries.

@item @kbd{s}
Schedule all items to a new date.  To shift existing schedule
dates by a fixed number of days, use something starting with
double plus at the prompt, for example @samp{++8d} or @samp{++2w}.

@item @kbd{d}
Set deadline to a specific date.

@item @kbd{r}
Prompt for a single refile target and move all entries.  The
entries are no longer in the agenda; refresh (@kbd{g}) to
bring them back.

@item @kbd{S}
Reschedule randomly into the coming N days.  N is prompted for.
With a prefix argument (@kbd{C-u B S}), scatter only across
weekdays.

@item @kbd{f}
@vindex org-agenda-bulk-custom-functions
Apply a function@footnote{You can also create persistent custom functions through
@code{org-agenda-bulk-custom-functions}.} to marked entries.  For example, the
function below sets the @samp{CATEGORY} property of the entries to
@samp{web}.

@lisp
(defun set-category ()
  (interactive "P")
  (let ((marker (or (org-get-at-bol 'org-hd-marker)
                    (org-agenda-error))))
    (org-with-point-at marker
      (org-back-to-heading t)
      (org-set-property "CATEGORY" "web"))))
@end lisp
@end table
@end table

@anchor{Calendar commands}
@subheading Calendar commands

@cindex calendar commands, from agenda

@table @asis
@item @kbd{c} (@code{org-agenda-goto-calendar})
@kindex c
@findex org-agenda-goto-calendar
Open the Emacs calendar and go to the date at point in the agenda.

@item @kbd{c} (@code{org-calendar-goto-agenda})
@kindex c
@findex org-calendar-goto-agenda
When in the calendar, compute and show the Org agenda for the date
at point.

@item @kbd{i} (@code{org-agenda-diary-entry})
@kindex i
@findex org-agenda-diary-entry

@cindex diary entries, creating from agenda
Insert a new entry into the diary, using the date at point and (for
block entries) the date at the mark.  This adds to the Emacs diary
file@footnote{This file is parsed for the agenda when
@code{org-agenda-include-diary} is set.}, in a way similar to the @kbd{i} command in the
calendar.  The diary file pops up in another window, where you can
add the entry.

@vindex org-agenda-diary-file
If you configure @code{org-agenda-diary-file} to point to an Org file,
Org creates entries in that file instead.  Most entries are stored
in a date-based outline tree that will later make it easy to archive
appointments from previous months/years.  The tree is built under an
entry with a @samp{DATE_TREE} property, or else with years as top-level
entries.  Emacs prompts you for the entry text---if you specify it,
the entry is created in @code{org-agenda-diary-file} without further
interaction.  If you directly press @kbd{@key{RET}} at the prompt
without typing text, the target file is shown in another window for
you to finish the entry there.  See also the @kbd{k r} command.

@item @kbd{M} (@code{org-agenda-phases-of-moon})
@kindex M
@findex org-agenda-phases-of-moon
Show the phases of the moon for the three months around current
date.

@item @kbd{S} (@code{org-agenda-sunrise-sunset})
@kindex S
@findex org-agenda-sunrise-sunset
Show sunrise and sunset times.  The geographical location must be
set with calendar variables, see the documentation for the Emacs
calendar.

@item @kbd{C} (@code{org-agenda-convert-date})
@kindex C
@findex org-agenda-convert-date
Convert the date at point into many other cultural and historic
calendars.

@item @kbd{H} (@code{org-agenda-holidays})
@kindex H
@findex org-agenda-holidays
Show holidays for three months around point date.
@end table

@anchor{Quit and exit}
@subheading Quit and exit

@table @asis
@item @kbd{q} (@code{org-agenda-quit})
@kindex q
@findex org-agenda-quit

Quit agenda, remove the agenda buffer.

@item @kbd{x} (@code{org-agenda-exit})
@kindex x
@findex org-agenda-exit

@cindex agenda files, removing buffers
Exit agenda, remove the agenda buffer and all buffers loaded by
Emacs for the compilation of the agenda.  Buffers created by the
user to visit Org files are not removed.
@end table

@node Custom Agenda Views
@section Custom Agenda Views

@cindex custom agenda views
@cindex agenda views, custom

Custom agenda commands serve two purposes: to store and quickly access
frequently used TODO and tags searches, and to create special
composite agenda buffers.  Custom agenda commands are accessible
through the dispatcher (see @ref{Agenda Dispatcher}), just like the
default commands.

@menu
* Storing searches::             Type once, use often.
* Block agenda::                 All the stuff you need in a single buffer.
* Setting options::              Changing the rules.
@end menu

@node Storing searches
@subsection Storing searches

The first application of custom searches is the definition of keyboard
shortcuts for frequently used searches, either creating an agenda
buffer, or a sparse tree (the latter covering of course only the
current buffer).

@kindex C @r{(Agenda dispatcher)}
@vindex org-agenda-custom-commands
@cindex agenda views, main example
@cindex agenda, as an agenda views
@cindex agenda*, as an agenda views
@cindex tags, as an agenda view
@cindex todo, as an agenda view
@cindex tags-todo
@cindex todo-tree
@cindex occur-tree
@cindex tags-tree
Custom commands are configured in the variable
@code{org-agenda-custom-commands}.  You can customize this variable, for
example by pressing @kbd{C} from the agenda dispatcher (see @ref{Agenda Dispatcher}).  You can also directly set it with Emacs Lisp in
the Emacs init file.  The following example contains all valid agenda
views:

@lisp
(setq org-agenda-custom-commands
      '(("x" agenda)
        ("y" agenda*)
        ("w" todo "WAITING")
        ("W" todo-tree "WAITING")
        ("u" tags "+boss-urgent")
        ("v" tags-todo "+boss-urgent")
        ("U" tags-tree "+boss-urgent")
        ("f" occur-tree "\\<FIXME\\>")
        ("h" . "HOME+Name tags searches") ;description for "h" prefix
        ("hl" tags "+home+Lisa")
        ("hp" tags "+home+Peter")
        ("hk" tags "+home+Kim")))
@end lisp

The initial string in each entry defines the keys you have to press
after the dispatcher command in order to access the command.  Usually
this is just a single character, but if you have many similar
commands, you can also define two-letter combinations where the first
character is the same in several combinations and serves as a prefix
key@footnote{You can provide a description for a prefix key by inserting
a cons cell with the prefix and the description.}.  The second parameter is the search type, followed by the
string or regular expression to be used for the matching.  The example
above will therefore define:

@table @asis
@item @kbd{x}
as a global search for agenda entries planned@footnote{@emph{Planned} means here that these entries have some planning
information attached to them, like a time-stamp, a scheduled or
a deadline string.  See @code{org-agenda-entry-types} on how to set what
planning information is taken into account.} this week/day.

@item @kbd{y}
as the same search, but only for entries with an hour specification
like @samp{[h]h:mm}---think of them as appointments.

@item @kbd{w}
as a global search for TODO entries with @samp{WAITING} as the TODO
keyword.

@item @kbd{W}
as the same search, but only in the current buffer and displaying
the results as a sparse tree.

@item @kbd{u}
as a global tags search for headlines tagged @samp{boss} but not
@samp{urgent}.

@item @kbd{v}
The same search, but limiting it to headlines that are also TODO
items.

@item @kbd{U}
as the same search, but only in the current buffer and displaying
the result as a sparse tree.

@item @kbd{f}
to create a sparse tree (again, current buffer only) with all
entries containing the word @samp{FIXME}.

@item @kbd{h}
as a prefix command for a @samp{HOME} tags search where you have to press
an additional key (@kbd{l}, @kbd{p} or @kbd{k}) to
select a name (Lisa, Peter, or Kim) as additional tag to match.
@end table

Note that @code{*-tree} agenda views need to be called from an Org buffer
as they operate on the current buffer only.

@node Block agenda
@subsection Block agenda

@cindex block agenda
@cindex agenda, with block views

Another possibility is the construction of agenda views that comprise
the results of @emph{several} commands, each of which creates a block in
the agenda buffer.  The available commands include @code{agenda} for the
daily or weekly agenda (as created with @kbd{a}) , @code{alltodo} for
the global TODO list (as constructed with @kbd{t}), and the
matching commands discussed above: @code{todo}, @code{tags}, and @code{tags-todo}.
Here are two examples:

@lisp
(setq org-agenda-custom-commands
      '(("h" "Agenda and Home-related tasks"
         ((agenda "")
          (tags-todo "home")
          (tags "garden")))
        ("o" "Agenda and Office-related tasks"
         ((agenda "")
          (tags-todo "work")
          (tags "office")))))
@end lisp

@noindent
This defines @kbd{h} to create a multi-block view for stuff you
need to attend to at home.  The resulting agenda buffer contains your
agenda for the current week, all TODO items that carry the tag @samp{home},
and also all lines tagged with @samp{garden}.  Finally the command
@kbd{o} provides a similar view for office tasks.

@node Setting options
@subsection Setting options for custom commands

@cindex options, for custom agenda views

@vindex org-agenda-custom-commands
Org mode contains a number of variables regulating agenda construction
and display.  The global variables define the behavior for all agenda
commands, including the custom commands.  However, if you want to
change some settings just for a single custom view, you can do so.
Setting options requires inserting a list of variable names and values
at the right spot in @code{org-agenda-custom-commands}.  For example:

@lisp
(setq org-agenda-custom-commands
      '(("w" todo "WAITING"
         ((org-agenda-sorting-strategy '(priority-down))
          (org-agenda-prefix-format "  Mixed: ")))
        ("U" tags-tree "+boss-urgent"
         ((org-show-context-detail 'minimal)))
        ("N" search ""
         ((org-agenda-files '("~org/notes.org"))
          (org-agenda-text-search-extra-files nil)))))
@end lisp

@noindent
Now the @kbd{w} command sorts the collected entries only by
priority, and the prefix format is modified to just say @samp{Mixed:}
instead of giving the category of the entry.  The sparse tags tree of
@kbd{U} now turns out ultra-compact, because neither the headline
hierarchy above the match, nor the headline following the match are
shown.  The command @kbd{N} does a text search limited to only
a single file.

For command sets creating a block agenda, @code{org-agenda-custom-commands}
has two separate spots for setting options.  You can add options that
should be valid for just a single command in the set, and options that
should be valid for all commands in the set.  The former are just
added to the command entry; the latter must come after the list of
command entries.  Going back to the block agenda example (see @ref{Block agenda}), let's change the sorting strategy for the @kbd{h}
commands to @code{priority-down}, but let's sort the results for @samp{garden}
tags query in the opposite order, @code{priority-up}.  This would look like
this:

@lisp
(setq org-agenda-custom-commands
      '(("h" "Agenda and Home-related tasks"
         ((agenda)
          (tags-todo "home")
          (tags "garden"
                ((org-agenda-sorting-strategy '(priority-up)))))
         ((org-agenda-sorting-strategy '(priority-down))))
        ("o" "Agenda and Office-related tasks"
         ((agenda)
          (tags-todo "work")
          (tags "office")))))
@end lisp

As you see, the values and parentheses setting is a little complex.
When in doubt, use the customize interface to set this variable---it
fully supports its structure.  Just one caveat: when setting options
in this interface, the @emph{values} are just Lisp expressions.  So if the
value is a string, you need to add the double-quotes around the value
yourself.

@vindex org-agenda-custom-commands-contexts
To control whether an agenda command should be accessible from
a specific context, you can customize
@code{org-agenda-custom-commands-contexts}.  Let's say for example that you
have an agenda command @kbd{o} displaying a view that you only
need when reading emails.  Then you would configure this option like
this:

@lisp
(setq org-agenda-custom-commands-contexts
      '(("o" (in-mode . "message-mode"))))
@end lisp

You can also tell that the command key @kbd{o} should refer to
another command key @kbd{r}.  In that case, add this command key
like this:

@lisp
(setq org-agenda-custom-commands-contexts
      '(("o" "r" (in-mode . "message-mode"))))
@end lisp

See the docstring of the variable for more information.

@node Exporting Agenda Views
@section Exporting Agenda Views

@cindex agenda views, exporting

If you are away from your computer, it can be very useful to have
a printed version of some agenda views to carry around.  Org mode can
export custom agenda views as plain text, HTML@footnote{For HTML you need to install Hrvoje Nikšić's @samp{htmlize.el}
as an Emacs package from MELPA or from @uref{https://github.com/hniksic/emacs-htmlize, Hrvoje Nikšić's repository}.}, Postscript,
PDF@footnote{To create PDF output, the Ghostscript ps2pdf utility must be
installed on the system.  Selecting a PDF file also creates the
postscript file.}, and iCalendar files.  If you want to do this only
occasionally, use the following command:

@table @asis
@item @kbd{C-x C-w} (@code{org-agenda-write})
@kindex C-x C-w
@findex org-agenda-write
@cindex exporting agenda views
@cindex agenda views, exporting

@vindex org-agenda-exporter-settings
Write the agenda view to a file.
@end table

If you need to export certain agenda views frequently, you can
associate any custom agenda command with a list of output file
names@footnote{If you want to store standard views like the weekly agenda or
the global TODO list as well, you need to define custom commands for
them in order to be able to specify file names.}.  Here is an example that first defines custom commands
for the agenda and the global TODO list, together with a number of
files to which to export them.  Then we define two block agenda
commands and specify file names for them as well.  File names can be
relative to the current working directory, or absolute.

@lisp
(setq org-agenda-custom-commands
      '(("X" agenda "" nil ("agenda.html" "agenda.ps"))
        ("Y" alltodo "" nil ("todo.html" "todo.txt" "todo.ps"))
        ("h" "Agenda and Home-related tasks"
         ((agenda "")
          (tags-todo "home")
          (tags "garden"))
         nil
         ("~/views/home.html"))
        ("o" "Agenda and Office-related tasks"
         ((agenda)
          (tags-todo "work")
          (tags "office"))
         nil
         ("~/views/office.ps" "~/calendars/office.ics"))))
@end lisp

The extension of the file name determines the type of export.  If it
is @samp{.html}, Org mode uses the htmlize package to convert the buffer to
HTML and save it to this file name.  If the extension is @samp{.ps},
@code{ps-print-buffer-with-faces} is used to produce Postscript output.  If
the extension is @samp{.ics}, iCalendar export is run export over all files
that were used to construct the agenda, and limit the export to
entries listed in the agenda.  Any other extension produces a plain
ASCII file.

The export files are @emph{not} created when you use one of those
commands interactively because this might use too much overhead.
Instead, there is a special command to produce @emph{all} specified
files in one step:

@table @asis
@item @kbd{e} (@code{org-store-agenda-views})
@kindex e @r{(Agenda dispatcher)}
@findex org-store-agenda-views
Export all agenda views that have export file names associated with
them.
@end table

You can use the options section of the custom agenda commands to also
set options for the export commands.  For example:

@lisp
(setq org-agenda-custom-commands
      '(("X" agenda ""
         ((ps-number-of-columns 2)
          (ps-landscape-mode t)
          (org-agenda-prefix-format " [ ] ")
          (org-agenda-with-colors nil)
          (org-agenda-remove-tags t))
         ("theagenda.ps"))))
@end lisp

@noindent
@vindex org-agenda-exporter-settings
This command sets two options for the Postscript exporter, to make it
print in two columns in landscape format---the resulting page can be
cut in two and then used in a paper agenda.  The remaining settings
modify the agenda prefix to omit category and scheduling information,
and instead include a checkbox to check off items.  We also remove the
tags to make the lines compact, and we do not want to use colors for
the black-and-white printer.  Settings specified in
@code{org-agenda-exporter-settings} also apply, e.g.,

@lisp
(setq org-agenda-exporter-settings
      '((ps-number-of-columns 2)
        (ps-landscape-mode t)
        (org-agenda-add-entry-text-maxlines 5)
        (htmlize-output-type 'css)))
@end lisp

@noindent
but the settings in @code{org-agenda-custom-commands} take precedence.

From the command line you may also use:

@example
emacs -eval (org-batch-store-agenda-views) -kill
@end example

@noindent
or, if you need to modify some parameters@footnote{Quoting depends on the system you use, please check the FAQ
for examples.}

@example
emacs -eval '(org-batch-store-agenda-views                      \
              org-agenda-span (quote month)                     \
              org-agenda-start-day "2007-11-01"                 \
              org-agenda-include-diary nil                      \
              org-agenda-files (quote ("~/org/project.org")))'  \
      -kill
@end example

@noindent
which creates the agenda views restricted to the file
@samp{~/org/project.org}, without diary entries and with a 30-day extent.

You can also extract agenda information in a way that allows further
processing by other programs.  See @ref{Extracting Agenda Information}, for
more information.

@node Agenda Column View
@section Using Column View in the Agenda

@cindex column view, in agenda
@cindex agenda, column view

Column view (see @ref{Column View}) is normally used to view and edit
properties embedded in the hierarchical structure of an Org file.  It
can be quite useful to use column view also from the agenda, where
entries are collected by certain criteria.

@table @asis
@item @kbd{C-c C-x C-c} (@code{org-agenda-columns})
@kindex C-c C-x C-c
@findex org-agenda-columns

Turn on column view in the agenda.
@end table

To understand how to use this properly, it is important to realize
that the entries in the agenda are no longer in their proper outline
environment.  This causes the following issues:

@enumerate
@item
@vindex org-columns-default-format-for-agenda
@vindex org-columns-default-format
Org needs to make a decision which columns format to use.  Since
the entries in the agenda are collected from different files, and
different files may have different columns formats, this is a
non-trivial problem.  Org first checks if
@code{org-overriding-columns-format} is currently set, and if so, takes
the format from there.  You should set this variable only in the
@emph{local settings section} of a custom agenda command (see @ref{Custom Agenda Views}) to make it valid for that specific agenda view.  If
no such binding exists, it checks, in sequence,
@code{org-columns-default-format-for-agenda}, the format associated with
the first item in the agenda (through a property or a @samp{#+COLUMNS}
setting in that buffer) and finally @code{org-columns-default-format}.

@item
@cindex @samp{CLOCKSUM}, special property
If any of the columns has a summary type defined (see @ref{Column attributes}), turning on column view in the agenda visits all
relevant agenda files and make sure that the computations of this
property are up to date.  This is also true for the special
@samp{CLOCKSUM} property.  Org then sums the values displayed in the
agenda.  In the daily/weekly agenda, the sums cover a single day;
in all other views they cover the entire block.

It is important to realize that the agenda may show the same entry
@emph{twice}---for example as scheduled and as a deadline---and it may
show two entries from the same hierarchy (for example a @emph{parent}
and its @emph{child}).  In these cases, the summation in the agenda
leads to incorrect results because some values count double.

@item
When the column view in the agenda shows the @samp{CLOCKSUM} property,
that is always the entire clocked time for this item.  So even in
the daily/weekly agenda, the clocksum listed in column view may
originate from times outside the current view.  This has the
advantage that you can compare these values with a column listing
the planned total effort for a task---one of the major
applications for column view in the agenda.  If you want
information about clocked time in the displayed period use clock
table mode (press @kbd{R} in the agenda).

@item
@cindex @samp{CLOCKSUM_T}, special property
When the column view in the agenda shows the @samp{CLOCKSUM_T} property,
that is always today's clocked time for this item.  So even in the
weekly agenda, the clocksum listed in column view only originates
from today.  This lets you compare the time you spent on a task for
today, with the time already spent---via @samp{CLOCKSUM}---and with
the planned total effort for it.
@end enumerate

@node Markup for Rich Contents
@chapter Markup for Rich Contents

Org is primarily about organizing and searching through your
plain-text notes.  However, it also provides a lightweight yet robust
markup language for rich text formatting and more.  For instance, you
may want to center or emphasize text.  Or you may need to insert
a formula or image in your writing.  Org offers syntax for all of this
and more.  Used in conjunction with the export framework (see
@ref{Exporting}), you can author beautiful documents in Org---like the fine
manual you are currently reading.

@menu
* Paragraphs::                   The basic unit of text.
* Emphasis and Monospace::       Bold, italic, etc.
* Subscripts and Superscripts::  Simple syntax for raising/lowering text.
* Special Symbols::              Greek letters and other symbols.
* Embedded @LaTeX{}::            LaTeX can be freely used inside Org documents.
* Literal Examples::             Source code examples with special formatting.
* Images::                       Display an image.
* Captions::                     Describe tables, images...
* Horizontal Rules::             Make a line.
* Creating Footnotes::           Edit and read footnotes.
@end menu

@node Paragraphs
@section Paragraphs

@cindex paragraphs, markup rules
Paragraphs are separated by at least one empty line.  If you need to
enforce a line break within a paragraph, use @samp{\\} at the end of
a line.

@cindex line breaks, markup rules
To preserve the line breaks, indentation and blank lines in a region,
but otherwise use normal formatting, you can use this construct, which
can also be used to format poetry.

@cindex @samp{BEGIN_VERSE}
@cindex verse blocks
@example
#+BEGIN_VERSE
 Great clouds overhead
 Tiny black birds rise and fall
 Snow covers Emacs

    ---AlexSchroeder
#+END_VERSE
@end example

When quoting a passage from another document, it is customary to
format this as a paragraph that is indented on both the left and the
right margin.  You can include quotations in Org documents like this:

@cindex @samp{BEGIN_QUOTE}
@cindex quote blocks
@example
#+BEGIN_QUOTE
Everything should be made as simple as possible,
but not any simpler ---Albert Einstein
#+END_QUOTE
@end example

If you would like to center some text, do it like this:

@cindex @samp{BEGIN_CENTER}
@cindex center blocks
@example
#+BEGIN_CENTER
Everything should be made as simple as possible, \\
but not any simpler
#+END_CENTER
@end example

@node Emphasis and Monospace
@section Emphasis and Monospace

@cindex underlined text, markup rules
@cindex bold text, markup rules
@cindex italic text, markup rules
@cindex verbatim text, markup rules
@cindex code text, markup rules
@cindex strike-through text, markup rules

You can make words @samp{*bold*}, @samp{/italic/}, @samp{_underlined_}, @samp{=verbatim=}
and @samp{~code~}, and, if you must, @samp{+strike-through+}.  Text in the code
and verbatim string is not processed for Org specific syntax; it is
exported verbatim.

@vindex org-fontify-emphasized-text
To turn off fontification for marked up text, you can set
@code{org-fontify-emphasized-text} to @code{nil}.  To narrow down the list of
available markup syntax, you can customize @code{org-emphasis-alist}.

@node Subscripts and Superscripts
@section Subscripts and Superscripts

@cindex subscript
@cindex superscript

@samp{^} and @samp{_} are used to indicate super- and subscripts.  To increase
the readability of ASCII text, it is not necessary, but OK, to
surround multi-character sub- and superscripts with curly braces.  For
example

@example
The radius of the sun is R_sun = 6.96 x 10^8 m.  On the other hand,
the radius of Alpha Centauri is R_@{Alpha Centauri@} = 1.28 x R_@{sun@}.
@end example

@vindex org-use-sub-superscripts
If you write a text where the underscore is often used in a different
context, Org's convention to always interpret these as subscripts can
get in your way.  Configure the variable @code{org-use-sub-superscripts} to
change this convention.  For example, when setting this variable to
@code{@{@}}, @samp{a_b} is not interpreted as a subscript, but @samp{a_@{b@}} is.

@table @asis
@item @kbd{C-c C-x \} (@code{org-toggle-pretty-entities})
@kindex C-c C-x \
@findex org-toggle-pretty-entities
This command formats sub- and superscripts in a WYSIWYM way.
@end table

@node Special Symbols
@section Special Symbols

@cindex math symbols
@cindex special symbols
@cindex entities

You can use @LaTeX{}-like syntax to insert special symbols---named
entities---like @samp{\alpha} to indicate the Greek letter, or @samp{\to} to indicate
an arrow.  Completion for these symbols is available, just type @samp{\}
and maybe a few letters, and press @kbd{M-@key{TAB}} to see possible
completions.  If you need such a symbol inside a word, terminate it
with a pair of curly brackets.  For example

@example
Pro tip: Given a circle \Gamma of diameter d, the length of its
circumference is \pi@{@}d.
@end example

@findex org-entities-help
@vindex org-entities-user
A large number of entities is provided, with names taken from both
HTML and @LaTeX{}; you can comfortably browse the complete list from
a dedicated buffer using the command @code{org-entities-help}.  It is also
possible to provide your own special symbols in the variable
@code{org-entities-user}.

During export, these symbols are transformed into the native format of
the exporter back-end.  Strings like @samp{\alpha} are exported as @samp{&alpha;} in
the HTML output, and as @samp{\(\alpha\)} in the @LaTeX{} output.  Similarly, @samp{\nbsp}
becomes @samp{&nbsp;} in HTML and @samp{~} in @LaTeX{}.

@cindex special symbols, in-buffer display
If you would like to see entities displayed as UTF-8 characters, use
the following command@footnote{You can turn this on by default by setting the variable
@code{org-pretty-entities}, or on a per-file base with the @samp{STARTUP} option
@samp{entitiespretty}.}:

@table @asis
@item @kbd{C-c C-x \} (@code{org-toggle-pretty-entities})
@kindex C-c C-x \
@findex org-toggle-pretty-entities

Toggle display of entities as UTF-8 characters.  This does not
change the buffer content which remains plain ASCII, but it overlays
the UTF-8 character for display purposes only.
@end table

@cindex shy hyphen, special symbol
@cindex dash, special symbol
@cindex ellipsis, special symbol
In addition to regular entities defined above, Org exports in
a special way@footnote{This behavior can be disabled with @samp{-} export setting (see
@ref{Export Settings}).} the following commonly used character
combinations: @samp{\-} is treated as a shy hyphen, @samp{--} and @samp{---} are
converted into dashes, and @samp{...} becomes a compact set of dots.

@node Embedded @LaTeX{}
@section Embedded @LaTeX{}

@cindex @TeX{} interpretation
@cindex @LaTeX{} interpretation

Plain ASCII is normally sufficient for almost all note taking.
Exceptions include scientific notes, which often require mathematical
symbols and the occasional formula.  @LaTeX{}@footnote{@LaTeX{} is a macro system based on Donald@tie{}E@.@tie{}Knuth's @TeX{}
system.  Many of the features described here as ``@LaTeX{}'' are really
from @TeX{}, but for simplicity I am blurring this distinction.} is widely used to
typeset scientific documents.  Org mode supports embedding @LaTeX{} code
into its files, because many academics are used to writing and reading
@LaTeX{} source code, and because it can be readily processed to produce
pretty output for a number of export back-ends.

@menu
* @LaTeX{} fragments::           Complex formulas made easy.
* Previewing @LaTeX{} fragments:: What will this snippet look like?
* CD@LaTeX{} mode::              Speed up entering of formulas.
@end menu

@node @LaTeX{} fragments
@subsection @LaTeX{} fragments

@cindex @LaTeX{} fragments

@vindex org-format-latex-header
Org mode can contain @LaTeX{} math fragments, and it supports ways to
process these for several export back-ends.  When exporting to @LaTeX{},
the code is left as it is.  When exporting to HTML, Org can use either
@uref{http://www.mathjax.org, MathJax} (see @ref{Math formatting in HTML export}) or transcode the math
into images (see @ref{Previewing @LaTeX{} fragments}).

@LaTeX{} fragments do not need any special marking at all.  The following
snippets are identified as @LaTeX{} source code:

@itemize
@item
Environments of any kind@footnote{When MathJax is used, only the environments recognized by
MathJax are processed.  When dvipng, dvisvgm, or ImageMagick suite is
used to create images, any @LaTeX{} environment is handled.}.  The only requirement is that the
@samp{\begin} statement appears on a new line, preceded by only
whitespace.

@item
Text within the usual @LaTeX{} math delimiters.  To avoid conflicts
with currency specifications, single @samp{$} characters are only
recognized as math delimiters if the enclosed text contains at most
two line breaks, is directly attached to the @samp{$} characters with no
whitespace in between, and if the closing @samp{$} is followed by
whitespace, punctuation or a dash.  For the other delimiters, there
is no such restriction, so when in doubt, use @samp{\(...\)} as inline
math delimiters.
@end itemize

@noindent
For example:

@example
\begin@{equation@}                        % arbitrary environments,
x=\sqrt@{b@}                              % even tables, figures
\end@{equation@}                          % etc

If $a^2=b$ and \( b=2 \), then the solution must be
either $$ a=+\sqrt@{2@} $$ or \[ a=-\sqrt@{2@} \].
@end example

@vindex org-export-with-latex
@LaTeX{} processing can be configured with the variable
@code{org-export-with-latex}.  The default setting is @code{t} which means
MathJax for HTML, and no processing for ASCII and @LaTeX{} back-ends.
You can also set this variable on a per-file basis using one of these
lines:

@multitable {aaaaaaaaaaaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{#+OPTIONS: tex:t}
@tab Do the right thing automatically (MathJax)
@item @samp{#+OPTIONS: tex:nil}
@tab Do not process @LaTeX{} fragments at all
@item @samp{#+OPTIONS: tex:verbatim}
@tab Verbatim export, for jsMath or so
@end multitable

@node Previewing @LaTeX{} fragments
@subsection Previewing @LaTeX{} fragments

@cindex @LaTeX{} fragments, preview

@vindex org-preview-latex-default-process
If you have a working @LaTeX{} installation and @samp{dvipng}, @samp{dvisvgm} or
@samp{convert} installed@footnote{These are respectively available at
@uref{http://sourceforge.net/projects/dvipng/}, @uref{http://dvisvgm.bplaced.net/}
and from the ImageMagick suite.  Choose the converter by setting the
variable @code{org-preview-latex-default-process} accordingly.}, @LaTeX{} fragments can be processed to
produce images of the typeset expressions to be used for inclusion
while exporting to HTML (see @ref{@LaTeX{} fragments}), or for inline
previewing within Org mode.

@vindex org-format-latex-options
@vindex org-format-latex-header
You can customize the variables @code{org-format-latex-options} and
@code{org-format-latex-header} to influence some aspects of the preview.
In particular, the @code{:scale} (and for HTML export, @code{:html-scale})
property of the former can be used to adjust the size of the preview
images.

@table @asis
@item @kbd{C-c C-x C-l} (@code{org-latex-preview})
@kindex C-c C-x C-l
@findex org-latex-preview

Produce a preview image of the @LaTeX{} fragment at point and overlay
it over the source code.  If there is no fragment at point, process
all fragments in the current entry---between two headlines.

When called with a single prefix argument, clear all images in the
current entry.  Two prefix arguments produce a preview image for all
fragments in the buffer, while three of them clear all the images in
that buffer.
@end table

@vindex org-startup-with-latex-preview
You can turn on the previewing of all @LaTeX{} fragments in a file with

@example
#+STARTUP: latexpreview
@end example


To disable it, simply use

@example
#+STARTUP: nolatexpreview
@end example

@node CD@LaTeX{} mode
@subsection Using CD@LaTeX{} to enter math

@cindex CD@LaTeX{}

CD@LaTeX{} mode is a minor mode that is normally used in combination with
a major @LaTeX{} mode like AUC@TeX{} in order to speed-up insertion of
environments and math templates.  Inside Org mode, you can make use of
some of the features of CD@LaTeX{} mode.  You need to install
@samp{cdlatex.el} and @samp{texmathp.el} (the latter comes also with AUC@TeX{})
using @uref{https://melpa.org/, MELPA} with the @uref{https://www.gnu.org/software/emacs/manual/html_node/emacs/Package-Installation.html, Emacs packaging system} or alternatively from
@uref{https://staff.fnwi.uva.nl/c.dominik/Tools/cdlatex/}.  Do not use
CD@LaTeX{} mode itself under Org mode, but use the special version Org
CD@LaTeX{} minor mode that comes as part of Org.  Turn it on for the
current buffer with @kbd{M-x org-cdlatex-mode}, or for all Org
files with

@lisp
(add-hook 'org-mode-hook 'turn-on-org-cdlatex)
@end lisp

When this mode is enabled, the following features are present (for
more details see the documentation of CD@LaTeX{} mode):

@table @asis
@item @kbd{C-c @{}
@kindex C-c @{

Insert an environment template.

@item @kbd{@key{TAB}}
@kindex TAB

The @kbd{@key{TAB}} key expands the template if point is inside
a @LaTeX{} fragment@footnote{Org mode has a method to test if point is inside such
a fragment, see the documentation of the function
@code{org-inside-LaTeX-fragment-p}.}.  For example, @kbd{@key{TAB}} expands @samp{fr}
to @samp{\frac@{@}@{@}} and position point correctly inside the first brace.
Another @kbd{@key{TAB}} gets you into the second brace.

Even outside fragments, @kbd{@key{TAB}} expands environment
abbreviations at the beginning of a line.  For example, if you write
@samp{equ} at the beginning of a line and press @kbd{@key{TAB}}, this
abbreviation is expanded to an @samp{equation} environment.  To get
a list of all abbreviations, type @kbd{M-x cdlatex-command-help}.

@item @kbd{^}
@itemx @kbd{_}
@kindex _
@kindex ^
@vindex cdlatex-simplify-sub-super-scripts

Pressing @kbd{_} and @kbd{^} inside a @LaTeX{} fragment
inserts these characters together with a pair of braces.  If you use
@kbd{@key{TAB}} to move out of the braces, and if the braces surround
only a single character or macro, they are removed again (depending
on the variable @code{cdlatex-simplify-sub-super-scripts}).

@item @kbd{`}
@kindex `

Pressing the backquote followed by a character inserts math macros,
also outside @LaTeX{} fragments.  If you wait more than 1.5 seconds
after the backquote, a help window pops up.

@item @kbd{'}
@kindex '

Pressing the single-quote followed by another character modifies the
symbol before point with an accent or a font.  If you wait more than
1.5 seconds after the single-quote, a help window pops up.
Character modification works only inside @LaTeX{} fragments; outside
the quote is normal.
@end table

@node Literal Examples
@section Literal Examples

@cindex literal examples, markup rules
@cindex code line references, markup rules

You can include literal examples that should not be subjected to
markup.  Such examples are typeset in monospace, so this is well
suited for source code and similar examples.

@cindex @samp{BEGIN_EXAMPLE}
@cindex example block
@example
#+BEGIN_EXAMPLE
  Some example from a text file.
#+END_EXAMPLE
@end example

@cindex comma escape, in literal examples
There is one limitation, however.  You must insert a comma right
before lines starting with either @samp{*}, @samp{,*}, @samp{#+} or @samp{,#+}, as those
may be interpreted as outlines nodes or some other special syntax.
Org transparently strips these additional commas whenever it accesses
the contents of the block.

@example
#+BEGIN_EXAMPLE
,* I am no real headline
#+END_EXAMPLE
@end example

For simplicity when using small examples, you can also start the
example lines with a colon followed by a space.  There may also be
additional whitespace before the colon:

@example
Here is an example
   : Some example from a text file.
@end example

@cindex formatting source code, markup rules
@vindex org-latex-listings
If the example is source code from a programming language, or any
other text that can be marked up by Font Lock in Emacs, you can ask
for the example to look like the fontified Emacs buffer@footnote{This works automatically for the HTML backend (it requires
version 1.34 of the @samp{htmlize.el} package, which you need to install).
Fontified code chunks in @LaTeX{} can be achieved using either the
@uref{https://www.ctan.org/pkg/listings, listings} package or the @uref{https://www.ctan.org/pkg/minted, minted} package.  Refer to
@code{org-export-latex-listings} for details.}.  This
is done with the code block, where you also need to specify the name
of the major mode that should be used to fontify the example@footnote{Source code in code blocks may also be evaluated either
interactively or on export.  See @ref{Working with Source Code} for more
information on evaluating code blocks.},
see @ref{Structure Templates} for shortcuts to easily insert code blocks.

@cindex @samp{BEGIN_SRC}
@cindex source block
@example
#+BEGIN_SRC emacs-lisp
  (defun org-xor (a b)
    "Exclusive or."
    (if a (not b) b))
 #+END_SRC
@end example

Both in @samp{example} and in @samp{src} snippets, you can add a @samp{-n} switch to
the end of the @samp{#+BEGIN} line, to get the lines of the example
numbered.  The @samp{-n} takes an optional numeric argument specifying the
starting line number of the block.  If you use a @samp{+n} switch, the
numbering from the previous numbered snippet is continued in the
current one.  The @samp{+n} switch can also take a numeric argument.  This
adds the value of the argument to the last line of the previous block
to determine the starting line number.

@example
#+BEGIN_SRC emacs-lisp -n 20
  ;; This exports with line number 20.
  (message "This is line 21")
#+END_SRC

#+BEGIN_SRC emacs-lisp +n 10
  ;; This is listed as line 31.
  (message "This is line 32")
#+END_SRC
@end example

In literal examples, Org interprets strings like @samp{(ref:name)} as
labels, and use them as targets for special hyperlinks like
@samp{[[(name)]]}---i.e., the reference name enclosed in single parenthesis.
In HTML, hovering the mouse over such a link remote-highlights the
corresponding code line, which is kind of cool.

You can also add a @samp{-r} switch which @emph{removes} the labels from the
source code@footnote{Adding @samp{-k} to @samp{-n -r} @emph{keeps} the labels in the source code
while using line numbers for the links, which might be useful to
explain those in an Org mode example code.}.  With the @samp{-n} switch, links to these references
are labeled by the line numbers from the code listing.  Otherwise
links use the labels with no parentheses.  Here is an example:

@example
#+BEGIN_SRC emacs-lisp -n -r
  (save-excursion                 (ref:sc)
     (goto-char (point-min))      (ref:jump)
#+END_SRC
In line [[(sc)]] we remember the current position. [[(jump)][Line (jump)]]
jumps to point-min.
@end example

@cindex indentation, in source blocks
Source code and examples may be @emph{indented} in order to align nicely
with the surrounding text, and in particular with plain list structure
(see @ref{Plain Lists}).  By default, Org only retains the relative
indentation between lines, e.g., when exporting the contents of the
block.  However, you can use the @samp{-i} switch to also preserve the
global indentation, if it does matter.  See @ref{Editing Source Code}.

@vindex org-coderef-label-format
If the syntax for the label format conflicts with the language syntax,
use a @samp{-l} switch to change the format, for example

@example
#+BEGIN_SRC pascal -n -r -l "((%s))"
@end example


@noindent
See also the variable @code{org-coderef-label-format}.

HTML export also allows examples to be published as text areas (see
@ref{Text areas in HTML export}).

Because the @samp{#+BEGIN} @dots{} @samp{#+END} patterns need to be added so often,
a shortcut is provided (see @ref{Structure Templates}).

@table @asis
@item @kbd{C-c '} (@code{org-edit-special})
@kindex C-c '
@findex org-edit-special
Edit the source code example at point in its native mode.  This
works by switching to a temporary buffer with the source code.  You
need to exit by pressing @kbd{C-c '} again.  The edited version
then replaces the old version in the Org buffer.  Fixed-width
regions---where each line starts with a colon followed by
a space---are edited using Artist mode@footnote{You may select a different mode with the variable
@code{org-edit-fixed-width-region-mode}.} to allow creating
ASCII drawings easily.  Using this command in an empty line creates
a new fixed-width region.
@end table

@cindex storing link, in a source code buffer
Calling @code{org-store-link} (see @ref{Handling Links}) while editing a source
code example in a temporary buffer created with @kbd{C-c '}
prompts for a label.  Make sure that it is unique in the current
buffer, and insert it with the proper formatting like @samp{(ref:label)} at
the end of the current line.  Then the label is stored as a link
@samp{(label)}, for retrieval with @kbd{C-c C-l}.

@node Images
@section Images

@cindex inlining images
@cindex images, markup rules
An image is a link to an image file@footnote{What Emacs considers to be an image depends on
@code{image-file-name-extensions} and @code{image-file-name-regexps}.} that does not have
a description part, for example

@example
./img/cat.jpg
@end example


If you wish to define a caption for the image (see @ref{Captions}) and
maybe a label for internal cross references (see @ref{Internal Links}),
make sure that the link is on a line by itself and precede it with
@samp{CAPTION} and @samp{NAME} keywords as follows:

@example
#+CAPTION: This is the caption for the next figure link (or table)
#+NAME:   fig:SED-HR4049
[[./img/a.jpg]]
@end example

Such images can be displayed within the buffer with the following
command:

@table @asis
@item @kbd{C-c C-x C-v} (@code{org-toggle-inline-images})
@kindex C-c C-x C-v
@findex org-toggle-inline-images
@vindex org-startup-with-inline-images
Toggle the inline display of linked images.  When called with
a prefix argument, also display images that do have a link
description.  You can ask for inline images to be displayed at
startup by configuring the variable
@code{org-startup-with-inline-images}@footnote{The variable @code{org-startup-with-inline-images} can be set
within a buffer with the @samp{STARTUP} options @samp{inlineimages} and
@samp{noinlineimages}.}.
@end table

@node Captions
@section Captions

@cindex captions, markup rules
@cindex @samp{CAPTION}, keyword

You can assign a caption to a specific part of a document by inserting
a @samp{CAPTION} keyword immediately before it:

@example
#+CAPTION: This is the caption for the next table (or link)
| ... | ... |
|-----+-----|
@end example

Optionally, the caption can take the form:

@example
#+CAPTION[Short caption]: Longer caption.
@end example


Even though images and tables are prominent examples of captioned
structures, the same caption mechanism can apply to many
others---e.g., @LaTeX{} equations, source code blocks.  Depending on the
export back-end, those may or may not be handled.

@node Horizontal Rules
@section Horizontal Rules

@cindex horizontal rules, markup rules
A line consisting of only dashes, and at least 5 of them, is exported
as a horizontal line.

@node Creating Footnotes
@section Creating Footnotes

@cindex footnotes

A footnote is started by a footnote marker in square brackets in
column 0, no indentation allowed.  It ends at the next footnote
definition, headline, or after two consecutive empty lines.  The
footnote reference is simply the marker in square brackets, inside
text.  Markers always start with @samp{fn:}.  For example:

@example
The Org homepage[fn:1] now looks a lot better than it used to.
...
[fn:1] The link is: https://orgmode.org
@end example

Org mode extends the number-based syntax to @emph{named} footnotes and
optional inline definition.  Here are the valid references:

@table @asis
@item @samp{[fn:NAME]}
A named footnote reference, where @var{NAME} is a unique
label word, or, for simplicity of automatic creation, a number.

@item @samp{[fn:: This is the inline definition of this footnote]}
An anonymous footnote where the definition is given directly at the
reference point.

@item @samp{[fn:NAME: a definition]}
An inline definition of a footnote, which also specifies a name for
the note.  Since Org allows multiple references to the same note,
you can then use @samp{[fn:NAME]} to create additional references.
@end table

@vindex org-footnote-auto-label
Footnote labels can be created automatically, or you can create names
yourself.  This is handled by the variable @code{org-footnote-auto-label}
and its corresponding @samp{STARTUP} keywords.  See the docstring of that
variable for details.

The following command handles footnotes:

@table @asis
@item @kbd{C-c C-x f}
The footnote action command.

@kindex C-c C-x f
When point is on a footnote reference, jump to the definition.  When
it is at a definition, jump to the---first---reference.

@vindex org-footnote-define-inline
@vindex org-footnote-section
Otherwise, create a new footnote.  Depending on the variable
@code{org-footnote-define-inline}@footnote{The corresponding in-buffer setting is: @samp{#+STARTUP: fninline}
or @samp{#+STARTUP: nofninline}.}, the definition is placed right
into the text as part of the reference, or separately into the
location determined by the variable @code{org-footnote-section}.

When this command is called with a prefix argument, a menu of
additional options is offered:

@multitable @columnfractions 0.1 0.9
@item @kbd{s}
@tab Sort the footnote definitions by reference sequence.
@item @kbd{r}
@tab Renumber the simple @samp{fn:N} footnotes.
@item @kbd{S}
@tab Short for first @kbd{r}, then @kbd{s} action.
@item @kbd{n}
@tab Rename all footnotes into a @samp{fn:1} @dots{} @samp{fn:n} sequence.
@item @kbd{d}
@tab Delete the footnote at point, including definition and references.
@end multitable

@vindex org-footnote-auto-adjust
Depending on the variable @code{org-footnote-auto-adjust}@footnote{The corresponding in-buffer options are @samp{#+STARTUP: fnadjust}
and @samp{#+STARTUP: nofnadjust}.},
renumbering and sorting footnotes can be automatic after each
insertion or deletion.

@item @kbd{C-c C-c}
@kindex C-c C-c
If point is on a footnote reference, jump to the definition.  If it
is at the definition, jump back to the reference.  When called at
a footnote location with a prefix argument, offer the same menu as
@kbd{C-c C-x f}.

@item @kbd{C-c C-o} or @kbd{mouse-1/2}
@kindex C-c C-o
@kindex mouse-1
@kindex mouse-2
Footnote labels are also links to the corresponding definition or
reference, and you can use the usual commands to follow these links.
@end table

@node Exporting
@chapter Exporting

@cindex exporting

At some point you might want to print your notes, publish them on the
web, or share them with people not using Org.  Org can convert and
export documents to a variety of other formats while retaining as much
structure (see @ref{Document Structure}) and markup (see @ref{Markup for Rich Contents}) as possible.

@cindex export back-end
The libraries responsible for translating Org files to other formats
are called @emph{back-ends}.  Org ships with support for the following
back-ends:

@itemize
@item
@emph{ascii} (ASCII format)
@item
@emph{beamer} (@LaTeX{} Beamer format)
@item
@emph{html} (HTML format)
@item
@emph{icalendar} (iCalendar format)
@item
@emph{latex} (@LaTeX{} format)
@item
@emph{md} (Markdown format)
@item
@emph{odt} (OpenDocument Text format)
@item
@emph{org} (Org format)
@item
@emph{texinfo} (Texinfo format)
@item
@emph{man} (Man page format)
@end itemize

Users can install libraries for additional formats from the Emacs
packaging system. For easy discovery, these packages have a common
naming scheme: @code{ox-NAME}, where @var{NAME} is a format.  For
example, @code{ox-koma-letter} for @emph{koma-letter} back-end.  More libraries
can be found in the @samp{contrib/} directory (see @ref{Installation}).

@vindex org-export-backends
Org only loads back-ends for the following formats by default: ASCII,
HTML, iCalendar, @LaTeX{}, and ODT@.  Additional back-ends can be loaded
in either of two ways: by configuring the @code{org-export-backends}
variable, or by requiring libraries in the Emacs init file.  For
example, to load the Markdown back-end, add this to your Emacs config:

@lisp
(require 'ox-md)
@end lisp

@menu
* The Export Dispatcher::        The main interface.
* Export Settings::              Common export settings.
* Table of Contents::            The if and where of the table of contents.
* Include Files::                Include additional files into a document.
* Macro Replacement::            Use macros to create templates.
* Comment Lines::                What will not be exported.
* ASCII/Latin-1/UTF-8 export::   Exporting to flat files with encoding.
* Beamer Export::                Producing presentations and slides.
* HTML Export::                  Exporting to HTML.
* @LaTeX{} Export::              Exporting to @LaTeX{} and processing to PDF.
* Markdown Export::              Exporting to Markdown.
* OpenDocument Text Export::     Exporting to OpenDocument Text.
* Org Export::                   Exporting to Org.
* Texinfo Export::               Exporting to Texinfo.
* iCalendar Export::             Exporting to iCalendar.
* Other Built-in Back-ends::     Exporting to a man page.
* Advanced Export Configuration:: Fine-tuning the export output.
* Export in Foreign Buffers::    Author tables and lists in Org syntax.
@end menu

@node The Export Dispatcher
@section The Export Dispatcher

@cindex dispatcher, for export commands
@cindex export, dispatcher

The export dispatcher is the main interface for Org's exports.
A hierarchical menu presents the currently configured export formats.
Options are shown as easy toggle switches on the same screen.

@vindex org-export-dispatch-use-expert-ui
Org also has a minimal prompt interface for the export dispatcher.
When the variable @code{org-export-dispatch-use-expert-ui} is set to
a non-@code{nil} value, Org prompts in the minibuffer.  To switch back to
the hierarchical menu, press @kbd{?}.

@table @asis
@item @kbd{C-c C-e} (@code{org-export})
@kindex C-c C-e
@findex org-export

Invokes the export dispatcher interface.  The options show default
settings.  The @kbd{C-u} prefix argument preserves options from
the previous export, including any sub-tree selections.
@end table

Org exports the entire buffer by default.  If the Org buffer has an
active region, then Org exports just that region.

Within the dispatcher interface, the following key combinations can
further alter what is exported, and how.

@table @asis
@item @kbd{C-a}
@kindex C-c C-e C-a

Toggle asynchronous export.  Asynchronous export uses an external
Emacs process with a specially configured initialization file to
complete the exporting process in the background, without tying-up
Emacs.  This is particularly useful when exporting long documents.

Output from an asynchronous export is saved on the @emph{export stack}.
To view this stack, call the export dispatcher with a double
@kbd{C-u} prefix argument.  If already in the export dispatcher
menu, @kbd{&} displays the stack.

@vindex org-export-in-background
You can make asynchronous export the default by setting
@code{org-export-in-background}.

@vindex org-export-async-init-file
You can set the initialization file used by the background process
by setting @code{org-export-async-init-file}.

@item @kbd{C-b}
@kindex C-c C-e C-b

Toggle body-only export.  Useful for excluding headers and footers
in the export.  Affects only those back-end formats that have
sections like @samp{<head>...</head>} in HTML@.

@item @kbd{C-s}
@kindex C-c C-e C-s

Toggle sub-tree export.  When turned on, Org exports only the
sub-tree starting from point position at the time the export
dispatcher was invoked.  Org uses the top heading of this sub-tree
as the document's title.  If point is not on a heading, Org uses the
nearest enclosing header.  If point is in the document preamble, Org
signals an error and aborts export.

@vindex org-export-initial-scope
To make sub-tree export the default, customize the variable
@code{org-export-initial-scope}.

@item @kbd{C-v}
@kindex C-c C-e C-v

Toggle visible-only export.  This is useful for exporting only
certain parts of an Org document by adjusting the visibility of
particular headings.
@end table

@node Export Settings
@section Export Settings

@cindex options, for export
@cindex Export, settings

@cindex @samp{OPTIONS}, keyword
Export options can be set: globally with variables; for an individual
file by making variables buffer-local with in-buffer settings (see
@ref{In-buffer Settings}); by setting individual keywords or
specifying them in compact form with the @samp{OPTIONS} keyword; or for
a tree by setting properties (see @ref{Properties and Columns}).  Options
set at a specific level override options set at a more general level.

@cindex @samp{SETUPFILE}, keyword
In-buffer settings may appear anywhere in the file, either directly or
indirectly through a file included using @samp{#+SETUPFILE: filename or
URL} syntax.  Option keyword sets tailored to a particular back-end
can be inserted from the export dispatcher (see @ref{The Export Dispatcher}) using the @samp{Insert template} command by pressing
@kbd{#}.  To insert keywords individually, a good way to make
sure the keyword is correct is to type @samp{#+} and then to use
@kbd{M-@key{TAB}}@footnote{Many desktops intercept @kbd{M-@key{TAB}} to switch windows.
Use @kbd{C-M-i} or @kbd{@key{ESC} @key{TAB}} instead.} for completion.

The export keywords available for every back-end, and their equivalent
global variables, include:

@table @asis
@item @samp{AUTHOR}
@cindex @samp{AUTHOR}, keyword
@vindex user-full-name
The document author (@code{user-full-name}).

@item @samp{CREATOR}
@cindex @samp{CREATOR}, keyword
@vindex org-expot-creator-string
Entity responsible for output generation
(@code{org-export-creator-string}).

@item @samp{DATE}
@cindex @samp{DATE}, keyword
@vindex org-export-date-timestamp-format
A date or a time-stamp@footnote{The variable @code{org-export-date-timestamp-format} defines how
this timestamp are exported.}.

@item @samp{EMAIL}
@cindex @samp{EMAIL}, keyword
@vindex user-mail-address
The email address (@code{user-mail-address}).

@item @samp{LANGUAGE}
@cindex @samp{LANGUAGE}, keyword
@vindex org-export-default-language
Language to use for translating certain strings
(@code{org-export-default-language}).  With @samp{#+LANGUAGE: fr}, for
example, Org translates @samp{Table of contents} to the French @samp{Table des
  matières}@footnote{For export to @LaTeX{} format---or @LaTeX{}-related formats such as
Beamer---, the @samp{org-latex-package-alist} variable needs further
configuration. See @ref{@LaTeX{} specific export settings}.}.

@item @samp{SELECT_TAGS}
@cindex @samp{SELECT_TAGS}, keyword
@vindex org-export-select-tags
The default value is @samp{("export")}.  When a tree is tagged with
@samp{export} (@code{org-export-select-tags}), Org selects that tree and its
sub-trees for export.  Org excludes trees with @samp{noexport} tags, see
below.  When selectively exporting files with @samp{export} tags set, Org
does not export any text that appears before the first headline.

@item @samp{EXCLUDE_TAGS}
@cindex @samp{EXCLUDE_TAGS}, keyword
@vindex org-export-exclude-tags
The default value is @samp{("noexport")}.  When a tree is tagged with
@samp{noexport} (@code{org-export-exclude-tags}), Org excludes that tree and
its sub-trees from export.  Entries tagged with @samp{noexport} are
unconditionally excluded from the export, even if they have an
@samp{export} tag.  Even if a sub-tree is not exported, Org executes any
code blocks contained there.

@item @samp{TITLE}
@cindex @samp{TITLE}, keyword
@cindex document title
Org displays this title.  For long titles, use multiple @samp{#+TITLE}
lines.

@item @samp{EXPORT_FILE_NAME}
@cindex @samp{EXPORT_FILE_NAME}, keyword
The name of the output file to be generated.  Otherwise, Org
generates the file name based on the buffer name and the extension
based on the back-end format.
@end table

The @samp{OPTIONS} keyword is a compact form.  To configure multiple
options, use several @samp{OPTIONS} lines.  @samp{OPTIONS} recognizes the
following arguments.

@table @asis
@item @code{'}
@vindex org-export-with-smart-quotes
Toggle smart quotes (@code{org-export-with-smart-quotes}).  Depending on
the language used, when activated, Org treats pairs of double quotes
as primary quotes, pairs of single quotes as secondary quotes, and
single quote marks as apostrophes.

@item @code{*}
@vindex org-export-with-emphasize
Toggle emphasized text (@code{org-export-with-emphasize}).

@item @code{-}
@vindex org-export-with-special-strings
Toggle conversion of special strings
(@code{org-export-with-special-strings}).

@item @code{:}
@vindex org-export-with-fixed-width
Toggle fixed-width sections (@code{org-export-with-fixed-width}).

@item @code{<}
@vindex org-export-with-timestamps
Toggle inclusion of time/date active/inactive stamps
(@code{org-export-with-timestamps}).

@item @code{\n}
@vindex org-export-preserve-breaks
Toggles whether to preserve line breaks
(@code{org-export-preserve-breaks}).

@item @code{^}
@vindex org-export-with-sub-superscripts
Toggle @TeX{}-like syntax for sub- and superscripts.  If you write
@samp{^:@{@}}, @samp{a_@{b@}} is interpreted, but the simple @samp{a_b} is left as it
is (@code{org-export-with-sub-superscripts}).

@item @code{arch}
@vindex org-export-with-archived-trees
Configure how archived trees are exported.  When set to @code{headline},
the export process skips the contents and processes only the
headlines (@code{org-export-with-archived-trees}).

@item @code{author}
@vindex org-export-with-author
Toggle inclusion of author name into exported file
(@code{org-export-with-author}).

@item @code{broken-links}
@vindex org-export-with-broken-links
Toggles if Org should continue exporting upon finding a broken
internal link.  When set to @code{mark}, Org clearly marks the problem
link in the output (@code{org-export-with-broken-links}).

@item @code{c}
@vindex org-export-with-clocks
Toggle inclusion of @samp{CLOCK} keywords (@code{org-export-with-clocks}).

@item @code{creator}
@vindex org-export-with-creator
Toggle inclusion of creator information in the exported file
(@code{org-export-with-creator}).

@item @code{d}
@vindex org-export-with-drawers
Toggles inclusion of drawers, or list of drawers to include, or list
of drawers to exclude (@code{org-export-with-drawers}).

@item @code{date}
@vindex org-export-with-date
Toggle inclusion of a date into exported file
(@code{org-export-with-date}).

@item @code{e}
@vindex org-export-with-entities
Toggle inclusion of entities (@code{org-export-with-entities}).

@item @code{email}
@vindex org-export-with-email
Toggle inclusion of the author's e-mail into exported file
(@code{org-export-with-email}).

@item @code{f}
@vindex org-export-with-footnotes
Toggle the inclusion of footnotes (@code{org-export-with-footnotes}).

@item @code{H}
@vindex org-export-headline-levels
Set the number of headline levels for export
(@code{org-export-headline-levels}).  Below that level, headlines are
treated differently.  In most back-ends, they become list items.

@item @code{inline}
@vindex org-export-with-inlinetasks
Toggle inclusion of inlinetasks (@code{org-export-with-inlinetasks}).

@item @code{num}
@vindex org-export-with-section-numbers
@cindex @samp{UNNUMBERED}, property
Toggle section-numbers (@code{org-export-with-section-numbers}).  When
set to number N, Org numbers only those headlines at level N or
above.  Set @samp{UNNUMBERED} property to non-@code{nil} to disable numbering
of heading and subheadings entirely.  Moreover, when the value is
@samp{notoc} the headline, and all its children, do not appear in the
table of contents either (see @ref{Table of Contents}).

@item @code{p}
@vindex org-export-with-planning
Toggle export of planning information (@code{org-export-with-planning}).
``Planning information'' comes from lines located right after the
headline and contain any combination of these cookies: @samp{SCHEDULED},
@samp{DEADLINE}, or @samp{CLOSED}.

@item @code{pri}
@vindex org-export-with-priority
Toggle inclusion of priority cookies
(@code{org-export-with-priority}).

@item @code{prop}
@vindex org-export-with-properties
Toggle inclusion of property drawers, or list the properties to
include (@code{org-export-with-properties}).

@item @code{stat}
@vindex org-export-with-statistics-cookies
Toggle inclusion of statistics cookies
(@code{org-export-with-statistics-cookies}).

@item @code{tags}
@vindex org-export-with-tags
Toggle inclusion of tags, may also be @code{not-in-toc}
(@code{org-export-with-tags}).

@item @code{tasks}
@vindex org-export-with-tasks
Toggle inclusion of tasks (TODO items); or @code{nil} to remove all
tasks; or @code{todo} to remove done tasks; or list the keywords to keep
(@code{org-export-with-tasks}).

@item @code{tex}
@vindex org-export-with-latex
@code{nil} does not export; @code{t} exports; @code{verbatim} keeps everything in
verbatim (@code{org-export-with-latex}).

@item @code{timestamp}
@vindex org-export-time-stamp-file
Toggle inclusion of the creation time in the exported file
(@code{org-export-time-stamp-file}).

@item @code{title}
@vindex org-export-with-title
Toggle inclusion of title (@code{org-export-with-title}).

@item @code{toc}
@vindex org-export-with-toc
Toggle inclusion of the table of contents, or set the level limit
(@code{org-export-with-toc}).

@item @code{todo}
@vindex org-export-with-todo-keywords
Toggle inclusion of TODO keywords into exported text
(@code{org-export-with-todo-keywords}).

@item @code{|}
@vindex org-export-with-tables
Toggle inclusion of tables (@code{org-export-with-tables}).
@end table

When exporting sub-trees, special node properties can override the
above keywords.  These properties have an @samp{EXPORT_} prefix.  For
example, @samp{DATE} becomes, @samp{EXPORT_DATE} when used for a specific
sub-tree.  Except for @samp{SETUPFILE}, all other keywords listed above
have an @samp{EXPORT_} equivalent.

@cindex @samp{BIND}, keyword
@vindex org-export-allow-bind-keywords
If @code{org-export-allow-bind-keywords} is non-@code{nil}, Emacs variables can
become buffer-local during export by using the @samp{BIND} keyword.  Its
syntax is @samp{#+BIND: variable value}.  This is particularly useful for
in-buffer settings that cannot be changed using keywords.

@node Table of Contents
@section Table of Contents

@cindex table of contents
@cindex list of tables
@cindex list of listings

@cindex @samp{toc}, in @samp{OPTIONS} keyword
@vindex org-export-with-toc
The table of contents includes all headlines in the document.  Its
depth is therefore the same as the headline levels in the file.  If
you need to use a different depth, or turn it off entirely, set the
@code{org-export-with-toc} variable accordingly.  You can achieve the same
on a per file basis, using the following @samp{toc} item in @samp{OPTIONS}
keyword:

@example
#+OPTIONS: toc:2          (only include two levels in TOC)
#+OPTIONS: toc:nil        (no default TOC at all)
@end example

@cindex excluding entries from table of contents
@cindex table of contents, exclude entries
Org includes both numbered and unnumbered headlines in the table of
contents@footnote{At the moment, some export back-ends do not obey this
specification.  For example, @LaTeX{} export excludes every unnumbered
headline from the table of contents.}.  If you need to exclude an unnumbered headline,
along with all its children, set the @samp{UNNUMBERED} property to @samp{notoc}
value.

@example
* Subtree not numbered, not in table of contents either
  :PROPERTIES:
  :UNNUMBERED: notoc
  :END:
@end example

@cindex @samp{TOC}, keyword
Org normally inserts the table of contents directly before the first
headline of the file.  To move the table of contents to a different
location, first turn off the default with @code{org-export-with-toc}
variable or with @samp{#+OPTIONS: toc:nil}.  Then insert @samp{#+TOC: headlines
N} at the desired location(s).

@example
#+OPTIONS: toc:nil
...
#+TOC: headlines 2
@end example

To adjust the table of contents depth for a specific section of the
Org document, append an additional @samp{local} parameter.  This parameter
becomes a relative depth for the current level.  The following example
inserts a local table of contents, with direct children only.

@example
* Section
#+TOC: headlines 1 local
@end example

Note that for this feature to work properly in @LaTeX{} export, the Org
file requires the inclusion of the titletoc package.  Because of
compatibility issues, titletoc has to be loaded @emph{before} hyperref.
Customize the @code{org-latex-default-packages-alist} variable.

The following example inserts a table of contents that links to the
children of the specified target.

@example
* Target
  :PROPERTIES:
  :CUSTOM_ID: TargetSection
  :END:
** Heading A
** Heading B
* Another section
#+TOC: headlines 1 :target #TargetSection
@end example

The @samp{:target} attribute is supported in HTML, Markdown, ODT, and ASCII export.

Use the @samp{TOC} keyword to generate list of tables---respectively, all
listings---with captions.

@example
#+TOC: listings
#+TOC: tables
@end example

@cindex @samp{ALT_TITLE}, property
Normally Org uses the headline for its entry in the table of contents.
But with @samp{ALT_TITLE} property, a different entry can be specified for
the table of contents.

@node Include Files
@section Include Files

@cindex include files, during export
@cindex export, include files
@cindex @samp{INCLUDE}, keyword

During export, you can include the content of another file.  For
example, to include your @samp{.emacs} file, you could use:

@example
#+INCLUDE: "~/.emacs" src emacs-lisp
@end example


@noindent
The first parameter is the file name to include.  The optional second
parameter specifies the block type: @samp{example}, @samp{export} or @samp{src}.  The
optional third parameter specifies the source code language to use for
formatting the contents.  This is relevant to both @samp{export} and @samp{src}
block types.

If an included file is specified as having a markup language, Org
neither checks for valid syntax nor changes the contents in any way.
For example and source blocks, Org code-escapes the contents before
inclusion.

@cindex @samp{minlevel}, include
If an included file is not specified as having any markup language,
Org assumes it be in Org format and proceeds as usual with a few
exceptions.  Org makes the footnote labels (see @ref{Creating Footnotes})
in the included file local to that file.  The contents of the included
file belong to the same structure---headline, item---containing the
@samp{INCLUDE} keyword.  In particular, headlines within the file become
children of the current section.  That behavior can be changed by
providing an additional keyword parameter, @samp{:minlevel}.  It shifts the
headlines in the included file to become the lowest level.  For
example, this syntax makes the included file a sibling of the current
top-level headline:

@example
#+INCLUDE: "~/my-book/chapter2.org" :minlevel 1
@end example


@cindex @samp{lines}, include
Inclusion of only portions of files are specified using ranges
parameter with @samp{:lines} keyword.  The line at the upper end of the
range will not be included.  The start and/or the end of the range may
be omitted to use the obvious defaults.

@multitable {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{#+INCLUDE: "~/.emacs" :lines "5-10"}
@tab Include lines 5 to 10, 10 excluded
@item @samp{#+INCLUDE: "~/.emacs" :lines "-10"}
@tab Include lines 1 to 10, 10 excluded
@item @samp{#+INCLUDE: "~/.emacs" :lines "10-"}
@tab Include lines from 10 to EOF
@end multitable

Inclusions may specify a file-link to extract an object matched by
@code{org-link-search}@footnote{Note that @code{org-link-search-must-match-exact-headline} is
locally bound to non-@code{nil}.  Therefore, @code{org-link-search} only matches
headlines and named elements.} (see @ref{Search Options}).  The
ranges for @samp{:lines} keyword are relative to the requested element.
Therefore,

@example
#+INCLUDE: "./paper.org::*conclusion" :lines 1-20
@end example


@noindent
includes the first 20 lines of the headline named @samp{conclusion}.

@cindex @samp{only-contents}, include
To extract only the contents of the matched object, set
@samp{:only-contents} property to non-@code{nil}.  This omits any planning lines
or property drawers.  For example, to include the body of the heading
with the custom ID @samp{theory}, you can use

@example
#+INCLUDE: "./paper.org::#theory" :only-contents t
@end example


The following command allows navigating to the included document:

@table @asis
@item @kbd{C-c '} (@code{org-edit~special})
@kindex C-c '
@findex org-edit-special

Visit the included file at point.
@end table

@node Macro Replacement
@section Macro Replacement

@cindex macro replacement, during export
@cindex @samp{MACRO}, keyword

@vindex org-export-global-macros
Macros replace text snippets during export.  Macros are defined
globally in @code{org-export-global-macros}, or document-wise with the
following syntax:

@example
#+MACRO: name   replacement text; $1, $2 are arguments
@end example


@noindent
which can be referenced using @samp{@{@{@{name(arg1, arg2)@}@}@}}@footnote{Since commas separate the arguments, commas within arguments
have to be escaped with the backslash character.  So only those
backslash characters before a comma need escaping with another
backslash character.}.  For
example

@example
#+MACRO: poem Rose is $1, violet's $2. Life's ordered: Org assists you.
@{@{@{poem(red,blue)@}@}@}
@end example

@noindent
becomes

@example
Rose is red, violet's blue. Life's ordered: Org assists you.
@end example


As a special case, Org parses any replacement text starting with
@samp{(eval} as an Emacs Lisp expression and evaluates it accordingly.
Within such templates, arguments become strings.  Thus, the following
macro

@example
#+MACRO: gnustamp (eval (concat "GNU/" (capitalize $1)))
@end example


@noindent
turns @samp{@{@{@{gnustamp(linux)@}@}@}} into @samp{GNU/Linux} during export.

Org recognizes macro references in following Org markup areas:
paragraphs, headlines, verse blocks, tables cells and lists.  Org also
recognizes macro references in keywords, such as @samp{CAPTION}, @samp{TITLE},
@samp{AUTHOR}, @samp{DATE}, and for some back-end specific export options.

Org comes with following pre-defined macros:

@table @asis
@item @samp{@{@{@{keyword(NAME)@}@}@}}
@itemx @samp{@{@{@{title@}@}@}}
@itemx @samp{@{@{@{author@}@}@}}
@itemx @samp{@{@{@{email@}@}@}}
@cindex @samp{keyword}, macro
@cindex @samp{title}, macro
@cindex @samp{author}, macro
@cindex @samp{email}, macro
The @samp{keyword} macro collects all values from @var{NAME}
keywords throughout the buffer, separated with white space.
@samp{title}, @samp{author} and @samp{email} macros are shortcuts for,
respectively, @samp{@{@{@{keyword(TITLE)@}@}@}}, @samp{@{@{@{keyword(AUTHOR)@}@}@}} and
@samp{@{@{@{keyword(EMAIL)@}@}@}}.

@item @samp{@{@{@{date@}@}@}}
@itemx @samp{@{@{@{date(FORMAT)@}@}@}}
@cindex @samp{date}, macro
This macro refers to the @samp{DATE} keyword.  @var{FORMAT} is an
optional argument to the @samp{date} macro that is used only if @samp{DATE} is
a single timestamp.  @var{FORMAT} should be a format string
understood by @code{format-time-string}.

@item @samp{@{@{@{time(FORMAT)@}@}@}}
@itemx @samp{@{@{@{modification-time(FORMAT, VC)@}@}@}}
@cindex @samp{time}, macro
@cindex @samp{modification-time}, macro
These macros refer to the document's date and time of export and
date and time of modification.  @var{FORMAT} is a string
understood by @code{format-time-string}.  If the second argument to the
@code{modification-time} macro is non-@code{nil}, Org uses @samp{vc.el} to retrieve
the document's modification time from the version control system.
Otherwise Org reads the file attributes.

@item @samp{@{@{@{input-file@}@}@}}
@cindex @samp{input-file}, macro
This macro refers to the filename of the exported file.

@item @samp{@{@{@{property(PROPERTY-NAME)@}@}@}}
@itemx @samp{@{@{@{property(PROPERTY-NAME, SEARCH OPTION)@}@}@}}
@cindex @samp{property}, macro
This macro returns the value of property @var{PROPERTY-NAME} in
the current entry.  If @var{SEARCH-OPTION} (see @ref{Search Options}) refers to a remote entry, use it instead.

@item @samp{@{@{@{n@}@}@}}
@itemx @samp{@{@{@{n(NAME)@}@}@}}
@itemx @samp{@{@{@{n(NAME, ACTION)@}@}@}}
@cindex @samp{n}, macro
@cindex counter, macro
This macro implements custom counters by returning the number of
times the macro has been expanded so far while exporting the buffer.
You can create more than one counter using different @var{NAME}
values.  If @var{ACTION} is @samp{-}, previous value of the counter
is held, i.e., the specified counter is not incremented.  If the
value is a number, the specified counter is set to that value.  If
it is any other non-empty string, the specified counter is reset
to 1.  You may leave @var{NAME} empty to reset the default
counter.
@end table

@cindex @samp{results}, macro
Moreover, inline source blocks (see @ref{Structure of Code Blocks}) use the
special @samp{results} macro to mark their output.  As such, you are
advised against re-defining it, unless you know what you are doing.

@vindex org-hide-macro-markers
The surrounding brackets can be made invisible by setting
@code{org-hide-macro-markers} to a non-@code{nil} value.

Org expands macros at the very beginning of the export process.

@node Comment Lines
@section Comment Lines

@cindex exporting, not

@cindex comment lines
Lines starting with zero or more whitespace characters followed by one
@samp{#} and a whitespace are treated as comments and, as such, are not
exported.

@cindex @samp{BEGIN_COMMENT}
@cindex comment block
Likewise, regions surrounded by @samp{#+BEGIN_COMMENT} @dots{} @samp{#+END_COMMENT}
are not exported.

@cindex comment trees
Finally, a @samp{COMMENT} keyword at the beginning of an entry, but after
any other keyword or priority cookie, comments out the entire subtree.
In this case, the subtree is not exported and no code block within it
is executed either@footnote{For a less drastic behavior, consider using a select tag (see
@ref{Export Settings}) instead.}.  The command below helps changing the
comment status of a headline.

@table @asis
@item @kbd{C-c ;} (@code{org-toggle-comment})
@kindex C-c ;
@findex org-toggle-comment

Toggle the @samp{COMMENT} keyword at the beginning of an entry.
@end table

@node ASCII/Latin-1/UTF-8 export
@section ASCII/Latin-1/UTF-8 export

@cindex ASCII export
@cindex Latin-1 export
@cindex UTF-8 export

ASCII export produces an output file containing only plain ASCII
characters.  This is the simplest and most direct text output.  It
does not contain any Org markup.  Latin-1 and UTF-8 export use
additional characters and symbols available in these encoding
standards.  All three of these export formats offer the most basic of
text output for maximum portability.

@vindex org-ascii-text-width
On export, Org fills and justifies text according to the text width
set in @code{org-ascii-text-width}.

@vindex org-ascii-links-to-notes
Org exports links using a footnote-like style where the descriptive
part is in the text and the link is in a note before the next heading.
See the variable @code{org-ascii-links-to-notes} for details.

@anchor{ASCII export commands}
@subheading ASCII export commands

@table @asis
@item @kbd{C-c C-e t a} (@code{org-ascii-export-to-ascii})
@itemx @kbd{C-c C-e t l}
@itemx @kbd{C-c C-e t u}
@kindex C-c C-e t a
@kindex C-c C-e t l
@kindex C-c C-e t u
@findex org-ascii-export-to-ascii

Export as an ASCII file with a @samp{.txt} extension.  For @samp{myfile.org},
Org exports to @samp{myfile.txt}, overwriting without warning.  For
@samp{myfile.txt}, Org exports to @samp{myfile.txt.txt} in order to prevent
data loss.

@item @kbd{C-c C-e t A} (@code{org-ascii-export-to-ascii})
@itemx @kbd{C-c C-e t L}
@itemx @kbd{C-c C-e t U}
@kindex C-c C-e t A
@kindex C-c C-e t L
@kindex C-c C-e t U
@findex org-ascii-export-as-ascii

Export to a temporary buffer.  Does not create a file.
@end table

@anchor{ASCII specific export settings}
@subheading ASCII specific export settings

The ASCII export back-end has one extra keyword for customizing ASCII
output.  Setting this keyword works similar to the general options
(see @ref{Export Settings}).

@table @asis
@item @samp{SUBTITLE}
@cindex @samp{SUBTITLE}, keyword
The document subtitle.  For long subtitles, use multiple
@samp{#+SUBTITLE} lines in the Org file.  Org prints them on one
continuous line, wrapping into multiple lines if necessary.
@end table

@anchor{Header and sectioning structure}
@subheading Header and sectioning structure

Org converts the first three outline levels into headlines for ASCII
export.  The remaining levels are turned into lists.  To change this
cut-off point where levels become lists, see @ref{Export Settings}.

@anchor{Quoting ASCII text}
@subheading Quoting ASCII text

To insert text within the Org file by the ASCII back-end, use one the
following constructs, inline, keyword, or export block:

@cindex @samp{ASCII}, keyword
@cindex @samp{BEGIN_EXPORT ascii}
@example
Inline text @@@@ascii:and additional text@@@@ within a paragraph.

#+ASCII: Some text

#+BEGIN_EXPORT ascii
Org exports text in this block only when using ASCII back-end.
#+END_EXPORT
@end example

@anchor{ASCII specific attributes}
@subheading ASCII specific attributes

@cindex @samp{ATTR_ASCII}, keyword
@cindex horizontal rules, in ASCII export

ASCII back-end recognizes only one attribute, @samp{:width}, which
specifies the width of a horizontal rule in number of characters.  The
keyword and syntax for specifying widths is:

@example
#+ATTR_ASCII: :width 10
-----
@end example

@anchor{ASCII special blocks}
@subheading ASCII special blocks

@cindex special blocks, in ASCII export
@cindex @samp{BEGIN_JUSTIFYLEFT}
@cindex @samp{BEGIN_JUSTIFYRIGHT}

Besides @samp{#+BEGIN_CENTER} blocks (see @ref{Paragraphs}), ASCII back-end has
these two left and right justification blocks:

@example
#+BEGIN_JUSTIFYLEFT
It's just a jump to the left...
#+END_JUSTIFYLEFT

#+BEGIN_JUSTIFYRIGHT
...and then a step to the right.
#+END_JUSTIFYRIGHT
@end example

@node Beamer Export
@section Beamer Export

@cindex Beamer export

Org uses Beamer export to convert an Org file tree structure into
high-quality interactive slides for presentations.  Beamer is a @LaTeX{}
document class for creating presentations in PDF, HTML, and other
popular display formats.

@menu
* Beamer export commands::       For creating Beamer documents.
* Beamer specific export settings:: For customizing Beamer export.
* Frames and Blocks in Beamer::  For composing Beamer slides.
* Beamer specific syntax::       For using in Org documents.
* Editing support::              Editing support.
* A Beamer example::             A complete presentation.
@end menu

@node Beamer export commands
@subsection Beamer export commands

@table @asis
@item @kbd{C-c C-e l b} (@code{org-beamer-export-to-latex})
@kindex C-c C-e l b
@findex org-beamer-export-to-latex

Export as @LaTeX{} file with a @samp{.tex} extension.  For @samp{myfile.org}, Org
exports to @samp{myfile.tex}, overwriting without warning.

@item @kbd{C-c C-e l B} (@code{org-beamer-export-as-latex})
@kindex C-c C-e l B
@findex org-beamer-export-as-latex

Export to a temporary buffer.  Does not create a file.

@item @kbd{C-c C-e l P} (@code{org-beamer-export-to-pdf})
@kindex C-c C-e l P
@findex org-beamer-export-to-pdf

Export as @LaTeX{} file and then convert it to PDF format.

@item @kbd{C-c C-e l O}
@kindex C-c C-e l O

Export as @LaTeX{} file, convert it to PDF format, and then open the
PDF file.
@end table

@node Beamer specific export settings
@subsection Beamer specific export settings

Beamer export back-end has several additional keywords for customizing
Beamer output.  These keywords work similar to the general options
settings (see @ref{Export Settings}).

@table @asis
@item @samp{BEAMER_THEME}
@cindex @samp{BEAMER_THEME}, keyword
@vindex org-beamer-theme
The Beamer layout theme (@code{org-beamer-theme}).  Use square brackets
for options.  For example:

@example
#+BEAMER_THEME: Rochester [height=20pt]
@end example

@item @samp{BEAMER_FONT_THEME}
@cindex @samp{BEAMER_FONT_THEME}, keyword
The Beamer font theme.

@item @samp{BEAMER_INNER_THEME}
@cindex @samp{BEAMER_INNER_THEME}, keyword
The Beamer inner theme.

@item @samp{BEAMER_OUTER_THEME}
@cindex @samp{BEAMER_OUTER_THEME}, keyword
The Beamer outer theme.

@item @samp{BEAMER_HEADER}
@cindex @samp{BEAMER_HEADER}, keyword
Arbitrary lines inserted in the preamble, just before the @samp{hyperref}
settings.

@item @samp{DESCRIPTION}
@cindex @samp{DESCRIPTION}, keyword
The document description.  For long descriptions, use multiple
@samp{DESCRIPTION} keywords.  By default, @samp{hyperref} inserts
@samp{DESCRIPTION} as metadata.  Use @code{org-latex-hyperref-template} to
configure document metadata.  Use @code{org-latex-title-command} to
configure typesetting of description as part of front matter.

@item @samp{KEYWORDS}
@cindex @samp{KEYWORDS}, keyword
The keywords for defining the contents of the document.  Use
multiple @samp{KEYWORDS} lines if necessary.  By default, @samp{hyperref}
inserts @samp{KEYWORDS} as metadata.  Use @code{org-latex-hyperref-template}
to configure document metadata.  Use @code{org-latex-title-command} to
configure typesetting of keywords as part of front matter.

@item @samp{SUBTITLE}
@cindex @samp{SUBTITLE}, keyword
Document's subtitle.  For typesetting, use
@code{org-beamer-subtitle-format} string.  Use
@code{org-latex-hyperref-template} to configure document metadata.  Use
@code{org-latex-title-command} to configure typesetting of subtitle as
part of front matter.
@end table

@node Frames and Blocks in Beamer
@subsection Frames and Blocks in Beamer

Org transforms heading levels into Beamer's sectioning elements,
frames and blocks.  Any Org tree with a not-too-deep-level nesting
should in principle be exportable as a Beamer presentation.

@itemize
@item
@vindex org-beamer-frame-level
Org headlines become Beamer frames when the heading level in Org is
equal to @code{org-beamer-frame-level} or @samp{H} value in a @samp{OPTIONS} line
(see @ref{Export Settings}).

@cindex @samp{BEAMER_ENV}, property
Org overrides headlines to frames conversion for the current tree of
an Org file if it encounters the @samp{BEAMER_ENV} property set to
@samp{frame} or @samp{fullframe}.  Org ignores whatever
@code{org-beamer-frame-level} happens to be for that headline level in
the Org tree.  In Beamer terminology, a full frame is a frame
without its title.

@item
Org exports a Beamer frame's objects as block environments.  Org can
enforce wrapping in special block types when @samp{BEAMER_ENV} property
is set@footnote{If @samp{BEAMER_ENV} is set, Org export adds @samp{B_environment} tag
to make it visible.  The tag serves as a visual aid and has no
semantic relevance.}.  For valid values see
@code{org-beamer-environments-default}.  To add more values, see
@code{org-beamer-environments-extra}.
@vindex org-beamer-environments-default
@vindex org-beamer-environments-extra

@item
@cindex @samp{BEAMER_REF}, property
If @samp{BEAMER_ENV} is set to @samp{appendix}, Org exports the entry as an
appendix.  When set to @samp{note}, Org exports the entry as a note
within the frame or between frames, depending on the entry's heading
level.  When set to @samp{noteNH}, Org exports the entry as a note
without its title.  When set to @samp{againframe}, Org exports the entry
with @samp{\againframe} command, which makes setting the @samp{BEAMER_REF}
property mandatory because @samp{\againframe} needs frame to resume.

When @samp{ignoreheading} is set, Org export ignores the entry's headline
but not its content.  This is useful for inserting content between
frames.  It is also useful for properly closing a @samp{column}
environment.  @@end itemize

@cindex @samp{BEAMER_ACT}, property
@cindex @samp{BEAMER_OPT}, property
When @samp{BEAMER_ACT} is set for a headline, Org export translates that
headline as an overlay or action specification.  When enclosed in
square brackets, Org export makes the overlay specification
a default.  Use @samp{BEAMER_OPT} to set any options applicable to the
current Beamer frame or block.  The Beamer export back-end wraps
with appropriate angular or square brackets.  It also adds the
@samp{fragile} option for any code that may require a verbatim block.

@cindex @samp{BEAMER_COL}, property
To create a column on the Beamer slide, use the @samp{BEAMER_COL}
property for its headline in the Org file.  Set the value of
@samp{BEAMER_COL} to a decimal number representing the fraction of the
total text width.  Beamer export uses this value to set the column's
width and fills the column with the contents of the Org entry.  If
the Org entry has no specific environment defined, Beamer export
ignores the heading.  If the Org entry has a defined environment,
Beamer export uses the heading as title.  Behind the scenes, Beamer
export automatically handles @LaTeX{} column separations for contiguous
headlines.  To manually adjust them for any unique configurations
needs, use the @samp{BEAMER_ENV} property.
@end itemize

@node Beamer specific syntax
@subsection Beamer specific syntax

Since Org's Beamer export back-end is an extension of the @LaTeX{}
back-end, it recognizes other @LaTeX{} specific syntax---for example,
@samp{#+LATEX:} or @samp{#+ATTR_LATEX:}.  See @ref{@LaTeX{} Export}, for details.

Beamer export wraps the table of contents generated with @samp{toc:t}
@samp{OPTION} keyword in a @samp{frame} environment.  Beamer export does not
wrap the table of contents generated with @samp{TOC} keyword (see @ref{Table of Contents}).  Use square brackets for specifying options.

@example
#+TOC: headlines [currentsection]
@end example


Insert Beamer-specific code using the following constructs:

@cindex @samp{BEAMER}, keyword
@cindex @samp{BEGIN_EXPORT beamer}
@example
#+BEAMER: \pause

#+BEGIN_EXPORT beamer
  Only Beamer export back-end exports this.
#+END_BEAMER

Text @@@@beamer:some code@@@@ within a paragraph.
@end example

Inline constructs, such as the last one above, are useful for adding
overlay specifications to objects with @code{bold}, @code{item}, @code{link},
@code{radio-target} and @code{target} types.  Enclose the value in angular
brackets and place the specification at the beginning of the object as
shown in this example:

@example
A *@@@@beamer:<2->@@@@useful* feature
@end example


@cindex @samp{ATTR_BEAMER}, keyword
Beamer export recognizes the @samp{ATTR_BEAMER} keyword with the following
attributes from Beamer configurations: @samp{:environment} for changing
local Beamer environment, @samp{:overlay} for specifying Beamer overlays in
angular or square brackets, and @samp{:options} for inserting optional
arguments.

@example
#+ATTR_BEAMER: :environment nonindentlist
- item 1, not indented
- item 2, not indented
- item 3, not indented
@end example

@example
#+ATTR_BEAMER: :overlay <+->
- item 1
- item 2
@end example

@example
#+ATTR_BEAMER: :options [Lagrange]
Let $G$ be a finite group, and let $H$ be
a subgroup of $G$.  Then the order of $H$ divides the order of $G$.
@end example

@node Editing support
@subsection Editing support

Org Beamer mode is a special minor mode for faster editing of Beamer
documents.

@example
#+STARTUP: beamer
@end example


@table @asis
@item @kbd{C-c C-b} (@code{org-beamer-select-environment})
@kindex C-c C-b
@findex org-beamer-select-environment

Org Beamer mode provides this key for quicker selections in Beamer
normal environments, and for selecting the @samp{BEAMER_COL} property.
@end table

@node A Beamer example
@subsection A Beamer example

Here is an example of an Org document ready for Beamer export.

@example
#+TITLE: Example Presentation
#+AUTHOR: Carsten Dominik
#+OPTIONS: H:2 toc:t num:t
#+LATEX_CLASS: beamer
#+LATEX_CLASS_OPTIONS: [presentation]
#+BEAMER_THEME: Madrid
#+COLUMNS: %45ITEM %10BEAMER_ENV(Env) %10BEAMER_ACT(Act) %4BEAMER_COL(Col)

* This is the first structural section

** Frame 1
*** Thanks to Eric Fraga                                           :B_block:
    :PROPERTIES:
    :BEAMER_COL: 0.48
    :BEAMER_ENV: block
    :END:
    for the first viable Beamer setup in Org
*** Thanks to everyone else                                        :B_block:
    :PROPERTIES:
    :BEAMER_COL: 0.48
    :BEAMER_ACT: <2->
    :BEAMER_ENV: block
    :END:
    for contributing to the discussion
**** This will be formatted as a beamer note                       :B_note:
     :PROPERTIES:
     :BEAMER_env: note
     :END:
** Frame 2 (where we will not use columns)
*** Request
    Please test this stuff!
@end example

@node HTML Export
@section HTML Export

@cindex HTML export

Org mode contains an HTML exporter with extensive HTML formatting
compatible with XHTML 1.0 strict standard.

@menu
* HTML export commands::         Invoking HTML export.
* HTML specific export settings:: Settings for HTML export.
* HTML doctypes::                Exporting various (X)HTML flavors.
* HTML preamble and postamble::  Inserting preamble and postamble.
* Quoting HTML tags::            Using direct HTML in Org files.
* Headlines in HTML export::     Formatting headlines.
* Links in HTML export::         Inserting and formatting links.
* Tables in HTML export::        How to modify the formatting of tables.
* Images in HTML export::        How to insert figures into HTML output.
* Math formatting in HTML export:: Beautiful math also on the web.
* Text areas in HTML export::    An alternate way to show an example.
* CSS support::                  Changing the appearance of the output.
* JavaScript support::           Info and folding in a web browser.
@end menu

@node HTML export commands
@subsection HTML export commands

@table @asis
@item @kbd{C-c C-e h h} (@code{org-html-export-to-html})
@kindex C-c C-e h h
@kindex C-c C-e h o
@findex org-html-export-to-html

Export as HTML file with a @samp{.html} extension.  For @samp{myfile.org}, Org
exports to @samp{myfile.html}, overwriting without warning.  @{@{@{kbd@{C-c
C-e h o)@}@}@} exports to HTML and opens it in a web browser.

@item @kbd{C-c C-e h H} (@code{org-html-export-as-html})
@kindex C-c C-e h H
@findex org-html-export-as-html

Exports to a temporary buffer.  Does not create a file.
@end table

@node HTML specific export settings
@subsection HTML specific export settings

HTML export has a number of keywords, similar to the general options
settings described in @ref{Export Settings}.

@table @asis
@item @samp{DESCRIPTION}
@cindex @samp{DESCRIPTION}, keyword
This is the document's description, which the HTML exporter inserts
it as a HTML meta tag in the HTML file.  For long descriptions, use
multiple @samp{DESCRIPTION} lines.  The exporter takes care of wrapping
the lines properly.

@item @samp{HTML_DOCTYPE}
@cindex @samp{HTML_DOCTYPE}, keyword
@vindex org-html-doctype
Specify the document type, for example: HTML5 (@code{org-html-doctype}).

@item @samp{HTML_CONTAINER}
@cindex @samp{HTML_CONTAINER}, keyword
@vindex org-html-container-element
Specify the HTML container, such as @samp{div}, for wrapping sections and
elements (@code{org-html-container-element}).

@item @samp{HTML_LINK_HOME}
@cindex @samp{HTML_LINK_HOME}, keyword
@vindex org-html-link-home
The URL for home link (@code{org-html-link-home}).

@item @samp{HTML_LINK_UP}
@cindex @samp{HTML_LINK_UP}, keyword
@vindex org-html-link-up
The URL for the up link of exported HTML pages (@code{org-html-link-up}).

@item @samp{HTML_MATHJAX}
@cindex @samp{HTML_MATHJAX}, keyword
@vindex org-html-mathjax-options
Options for MathJax (@code{org-html-mathjax-options}).  MathJax is used
to typeset @LaTeX{} math in HTML documents.  See @ref{Math formatting in HTML export}, for an example.

@item @samp{HTML_HEAD}
@cindex @samp{HTML_HEAD}, keyword
@vindex org-html-head
Arbitrary lines for appending to the HTML document's head
(@code{org-html-head}).

@item @samp{HTML_HEAD_EXTRA}
@cindex @samp{HTML_HEAD_EXTRA}, keyword
@vindex org-html-head-extra
More arbitrary lines for appending to the HTML document's head
(@code{org-html-head-extra}).

@item @samp{KEYWORDS}
@cindex @samp{KEYWORDS}, keyword
Keywords to describe the document's content.  HTML exporter inserts
these keywords as HTML meta tags.  For long keywords, use multiple
@samp{KEYWORDS} lines.

@item @samp{LATEX_HEADER}
@cindex @samp{LATEX_HEADER}, keyword
Arbitrary lines for appending to the preamble; HTML exporter appends
when transcoding @LaTeX{} fragments to images (see @ref{Math formatting in HTML export}).

@item @samp{SUBTITLE}
@cindex @samp{SUBTITLE}, keyword
The document's subtitle.  HTML exporter formats subtitle if document
type is @samp{HTML5} and the CSS has a @samp{subtitle} class.
@end table

Some of these keywords are explained in more detail in the following
sections of the manual.

@node HTML doctypes
@subsection HTML doctypes

Org can export to various (X)HTML flavors.

@vindex org-html-doctype
@vindex org-html-doctype-alist
Set the @code{org-html-doctype} variable for different (X)HTML variants.
Depending on the variant, the HTML exporter adjusts the syntax of HTML
conversion accordingly.  Org includes the following ready-made
variants:

@itemize
@item
@code{"html4-strict"}
@item
@code{"html4-transitional"}
@item
@code{"html4-frameset"}
@item
@code{"xhtml-strict"}
@item
@code{"xhtml-transitional"}
@item
@code{"xhtml-frameset"}
@item
@code{"xhtml-11"}
@item
@code{"html5"}
@item
@code{"xhtml5"}
@end itemize

@noindent
See the variable @code{org-html-doctype-alist} for details.  The default is
@code{"xhtml-strict"}.

@vindex org-html-html5-fancy
@cindex @samp{HTML5}, export new elements
Org's HTML exporter does not by default enable new block elements
introduced with the HTML5 standard.  To enable them, set
@code{org-html-html5-fancy} to non-@code{nil}.  Or use an @samp{OPTIONS} line in the
file to set @samp{html5-fancy}.

HTML5 documents can now have arbitrary @samp{#+BEGIN} @dots{} @samp{#+END} blocks.
For example:

@example
#+BEGIN_aside
  Lorem ipsum
#+END_aside
@end example

@noindent
exports to:

@example
<aside>
  <p>Lorem ipsum</p>
</aside>
@end example

@noindent
while this:

@example
#+ATTR_HTML: :controls controls :width 350
#+BEGIN_video
#+HTML: <source src="movie.mp4" type="video/mp4">
#+HTML: <source src="movie.ogg" type="video/ogg">
Your browser does not support the video tag.
#+END_video
@end example

@noindent
exports to:

@example
<video controls="controls" width="350">
  <source src="movie.mp4" type="video/mp4">
    <source src="movie.ogg" type="video/ogg">
      <p>Your browser does not support the video tag.</p>
</video>
@end example

@vindex org-html-html5-elements
When special blocks do not have a corresponding HTML5 element, the
HTML exporter reverts to standard translation (see
@code{org-html-html5-elements}).  For example, @samp{#+BEGIN_lederhosen} exports
to @code{<div class="lederhosen">}.

Special blocks cannot have headlines.  For the HTML exporter to wrap
the headline and its contents in @code{<section>} or @code{<article>} tags, set
the @samp{HTML_CONTAINER} property for the headline.

@node HTML preamble and postamble
@subsection HTML preamble and postamble

@vindex org-html-preamble
@vindex org-html-postamble
@vindex org-html-preamble-format
@vindex org-html-postamble-format
@vindex org-html-validation-link
@vindex org-export-creator-string
@vindex org-export-time-stamp-file

The HTML exporter has delineations for preamble and postamble.  The
default value for @code{org-html-preamble} is @code{t}, which makes the HTML
exporter insert the preamble.  See the variable
@code{org-html-preamble-format} for the format string.

Set @code{org-html-preamble} to a string to override the default format
string.  If the string is a function, the HTML exporter expects the
function to return a string upon execution.  The HTML exporter inserts
this string in the preamble.  The HTML exporter does not insert
a preamble if @code{org-html-preamble} is set @code{nil}.

The default value for @code{org-html-postamble} is @code{auto}, which makes the
HTML exporter build a postamble from looking up author's name, email
address, creator's name, and date.  Set @code{org-html-postamble} to @code{t} to
insert the postamble in the format specified in the
@code{org-html-postamble-format} variable.  The HTML exporter does not
insert a postamble if @code{org-html-postamble} is set to @code{nil}.

@node Quoting HTML tags
@subsection Quoting HTML tags

The HTML export back-end transforms @samp{<} and @samp{>} to @samp{&lt;} and @samp{&gt;}.
To include raw HTML code in the Org file so the HTML export back-end
can insert that HTML code in the output, use this inline syntax:
@samp{@@@@html:...@@@@}.  For example:

@example
@@@@html:<b>@@@@bold text@@@@html:</b>@@@@
@end example


@cindex @samp{HTML}, keyword
@cindex @samp{BEGIN_EXPORT html}
For larger raw HTML code blocks, use these HTML export code blocks:

@example
#+HTML: Literal HTML code for export

#+BEGIN_EXPORT html
  All lines between these markers are exported literally
#+END_EXPORT
@end example

@node Headlines in HTML export
@subsection Headlines in HTML export

@cindex headlines, in HTML export

Headlines are exported to @samp{<h1>}, @samp{<h2>}, etc.  Each headline gets the
@samp{id} attribute from @samp{CUSTOM_ID} property, or a unique generated value,
see @ref{Internal Links}.

@vindex org-html-self-link-headlines
When @code{org-html-self-link-headlines} is set to a non-@code{nil} value, the
text of the headlines is also wrapped in @samp{<a>} tags.  These tags have
a @samp{href} attribute making the headlines link to themselves.

@node Links in HTML export
@subsection Links in HTML export

@cindex links, in HTML export
@cindex internal links, in HTML export
@cindex external links, in HTML export

The HTML export back-end transforms Org's internal links (see
@ref{Internal Links}) to equivalent HTML links in the output.  The back-end
similarly handles Org's automatic links created by radio targets (see
@ref{Radio Targets}) similarly.  For Org links to external files, the
back-end transforms the links to @emph{relative} paths.

@vindex org-html-link-org-files-as-html
For Org links to other @samp{.org} files, the back-end automatically
changes the file extension to @samp{.html} and makes file paths relative.
If the @samp{.org} files have an equivalent @samp{.html} version at the same
location, then the converted links should work without any further
manual intervention.  However, to disable this automatic path
translation, set @code{org-html-link-org-files-as-html} to @code{nil}.  When
disabled, the HTML export back-end substitutes the ID-based links in
the HTML output.  For more about linking files when publishing to
a directory, see @ref{Publishing links}.

Org files can also have special directives to the HTML export
back-end.  For example, by using @samp{#+ATTR_HTML} lines to specify new
format attributes to @code{<a>} or @code{<img>} tags.  This example shows
changing the link's title and style:

@cindex @samp{ATTR_HTML}, keyword
@example
#+ATTR_HTML: :title The Org mode homepage :style color:red;
[[https://orgmode.org]]
@end example

@node Tables in HTML export
@subsection Tables in HTML export

@cindex tables, in HTML
@vindex org-export-html-table-tag

The HTML export back-end uses @code{org-html-table-default-attributes} when
exporting Org tables to HTML@.  By default, the exporter does not draw
frames and cell borders.  To change for this for a table, use the
following lines before the table in the Org file:

@cindex @samp{CAPTION}, keyword
@cindex @samp{ATTR_HTML}, keyword
@example
#+CAPTION: This is a table with lines around and between cells
#+ATTR_HTML: border="2" rules="all" frame="border"
@end example

The HTML export back-end preserves column groupings in Org tables (see
@ref{Column Groups}) when exporting to HTML@.

Additional options for customizing tables for HTML export.

@table @asis
@item @code{org-html-table-align-individual-fields}
@vindex org-html-table-align-individual-fields
Non-@code{nil} attaches style attributes for alignment to each table
field.

@item @code{org-html-table-caption-above}
@vindex org-html-table-caption-above
Non-@code{nil} places caption string at the beginning of the table.

@item @code{org-html-table-data-tags}
@vindex org-html-table-data-tags
Opening and ending tags for table data fields.

@item @code{org-html-table-default-attributes}
@vindex org-html-table-default-attributes
Default attributes and values for table tags.

@item @code{org-html-table-header-tags}
@vindex org-html-table-header-tags
Opening and ending tags for table's header fields.

@item @code{org-html-table-row-tags}
@vindex org-html-table-row-tags
Opening and ending tags for table rows.

@item @code{org-html-table-use-header-tags-for-first-column}
@vindex org-html-table-use-header-tags-for-first-column
Non-@code{nil} formats column one in tables with header tags.
@end table

@node Images in HTML export
@subsection Images in HTML export

@cindex images, inline in HTML
@cindex inlining images in HTML

The HTML export back-end has features to convert Org image links to
HTML inline images and HTML clickable image links.

@vindex org-html-inline-images
When the link in the Org file has no description, the HTML export
back-end by default in-lines that image.  For example:
@samp{[[file:myimg.jpg]]} is in-lined, while @samp{[[file:myimg.jpg][the image]]} links to the text,
@samp{the image}.  For more details, see the variable
@code{org-html-inline-images}.

On the other hand, if the description part of the Org link is itself
another link, such as @samp{file:} or @samp{http:} URL pointing to an image, the
HTML export back-end in-lines this image and links to the main image.
This Org syntax enables the back-end to link low-resolution thumbnail
to the high-resolution version of the image, as shown in this example:

@example
[[file:highres.jpg][file:thumb.jpg]]
@end example


To change attributes of in-lined images, use @samp{#+ATTR_HTML} lines in
the Org file.  This example shows realignment to right, and adds @code{alt}
and @code{title} attributes in support of text viewers and modern web
accessibility standards.

@cindex @samp{CAPTION}, keyword
@cindex @samp{ATTR_HTML}, keyword
@example
#+CAPTION: A black cat stalking a spider
#+ATTR_HTML: :alt cat/spider image :title Action! :align right
[[./img/a.jpg]]
@end example

The HTML export back-end copies the @samp{http} links from the Org file
as-is.

@node Math formatting in HTML export
@subsection Math formatting in HTML export

@cindex MathJax
@cindex dvipng
@cindex dvisvgm
@cindex ImageMagick

@vindex org-html-mathjax-options~
@LaTeX{} math snippets (see @ref{@LaTeX{} fragments}) can be displayed in two
different ways on HTML pages.  The default is to use the @uref{http://www.mathjax.org, MathJax},
which should work out of the box with Org@footnote{By default Org loads MathJax from @uref{https://cdnjs.com, cdnjs.com} as recommended by
@uref{http://www.mathjax.org, MathJax}.}@footnote{Please note that exported formulas are part of an HTML
document, and that signs such as @samp{<}, @samp{>}, or @samp{&} have special
meanings.  See @uref{http://docs.mathjax.org/en/latest/tex.html#tex-and-latex-in-html-documents, MathJax @TeX{} and @LaTeX{} support}.}.  Some MathJax
display options can be configured via @code{org-html-mathjax-options}, or
in the buffer.  For example, with the following settings,

@example
#+HTML_MATHJAX: align: left indent: 5em tagside: left font: Neo-Euler
#+HTML_MATHJAX: cancel.js noErrors.js
@end example

@noindent
equation labels are displayed on the left margin and equations are
five em from the left margin.  In addition, it loads the two MathJax
extensions @samp{cancel.js} and @samp{noErrors.js}@footnote{See @uref{http://docs.mathjax.org/en/latest/tex.html#tex-extensions, @TeX{} and @LaTeX{} extensions} in the @uref{http://docs.mathjax.org, MathJax manual} to learn
about extensions.}.

@vindex org-html-mathjax-template
See the docstring of @code{org-html-mathjax-options} for all supported
variables.  The MathJax template can be configure via
@code{org-html-mathjax-template}.

If you prefer, you can also request that @LaTeX{} fragments are processed
into small images that will be inserted into the browser page.  Before
the availability of MathJax, this was the default method for Org
files.  This method requires that the dvipng program, dvisvgm or
ImageMagick suite is available on your system.  You can still get this
processing with

@example
#+OPTIONS: tex:dvipng
@end example


@example
#+OPTIONS: tex:dvisvgm
@end example


@noindent
or

@example
#+OPTIONS: tex:imagemagick
@end example

@node Text areas in HTML export
@subsection Text areas in HTML export

@cindex text areas, in HTML
Before Org mode's Babel, one popular approach to publishing code in
HTML was by using @samp{:textarea}.  The advantage of this approach was
that copying and pasting was built into browsers with simple
JavaScript commands.  Even editing before pasting was made simple.

The HTML export back-end can create such text areas.  It requires an
@samp{#+ATTR_HTML} line as shown in the example below with the @samp{:textarea}
option.  This must be followed by either an example or a source code
block.  Other Org block types do not honor the @samp{:textarea} option.

By default, the HTML export back-end creates a text area 80 characters
wide and height just enough to fit the content.  Override these
defaults with @samp{:width} and @samp{:height} options on the @samp{#+ATTR_HTML}
line.

@example
#+ATTR_HTML: :textarea t :width 40
#+BEGIN_EXAMPLE
  (defun org-xor (a b)
     "Exclusive or."
     (if a (not b) b))
#+END_EXAMPLE
@end example

@node CSS support
@subsection CSS support

@cindex CSS, for HTML export
@cindex HTML export, CSS

@vindex org-export-html-todo-kwd-class-prefix
@vindex org-export-html-tag-class-prefix
You can modify the CSS style definitions for the exported file.  The
HTML exporter assigns the following special CSS classes@footnote{If the classes on TODO keywords and tags lead to conflicts,
use the variables @code{org-html-todo-kwd-class-prefix} and
@code{org-html-tag-class-prefix} to make them unique.} to
appropriate parts of the document---your style specifications may
change these, in addition to any of the standard classes like for
headlines, tables, etc.

@multitable {aaaaaaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @code{p.author}
@tab author information, including email
@item @code{p.date}
@tab publishing date
@item @code{p.creator}
@tab creator info, about org mode version
@item @code{.title}
@tab document title
@item @code{.subtitle}
@tab document subtitle
@item @code{.todo}
@tab TODO keywords, all not-done states
@item @code{.done}
@tab the DONE keywords, all states that count as done
@item @code{.WAITING}
@tab each TODO keyword also uses a class named after itself
@item @code{.timestamp}
@tab timestamp
@item @code{.timestamp-kwd}
@tab keyword associated with a timestamp, like @samp{SCHEDULED}
@item @code{.timestamp-wrapper}
@tab span around keyword plus timestamp
@item @code{.tag}
@tab tag in a headline
@item @code{._HOME}
@tab each tag uses itself as a class, ``@@'' replaced by ``_''
@item @code{.target}
@tab target for links
@item @code{.linenr}
@tab the line number in a code example
@item @code{.code-highlighted}
@tab for highlighting referenced code lines
@item @code{div.outline-N}
@tab div for outline level N (headline plus text)
@item @code{div.outline-text-N}
@tab extra div for text at outline level N
@item @code{.section-number-N}
@tab section number in headlines, different for each level
@item @code{.figure-number}
@tab label like ``Figure 1:''
@item @code{.table-number}
@tab label like ``Table 1:''
@item @code{.listing-number}
@tab label like ``Listing 1:''
@item @code{div.figure}
@tab how to format an in-lined image
@item @code{pre.src}
@tab formatted source code
@item @code{pre.example}
@tab normal example
@item @code{p.verse}
@tab verse paragraph
@item @code{div.footnotes}
@tab footnote section headline
@item @code{p.footnote}
@tab footnote definition paragraph, containing a footnote
@item @code{.footref}
@tab a footnote reference number (always a <sup>)
@item @code{.footnum}
@tab footnote number in footnote definition (always <sup>)
@item @code{.org-svg}
@tab default class for a linked @samp{.svg} image
@end multitable

@vindex org-html-style-default
@vindex org-html-head
@vindex org-html-head-extra
@cindex @samp{HTML_INCLUDE_STYLE}, keyword
The HTML export back-end includes a compact default style in each
exported HTML file.  To override the default style with another style,
use these keywords in the Org file.  They will replace the global
defaults the HTML exporter uses.

@cindex @samp{HTML_HEAD}, keyword
@cindex @samp{HTML_HEAD_EXTRA}, keyword
@example
#+HTML_HEAD: <link rel="stylesheet" type="text/css" href="style1.css" />
#+HTML_HEAD_EXTRA: <link rel="alternate stylesheet" type="text/css" href="style2.css" />
@end example

@vindex org-html-head-include-default-style
To just turn off the default style, customize
@code{org-html-head-include-default-style} variable, or use this option
line in the Org file.

@cindex @samp{html-style}, @samp{OPTIONS} item
@example
#+OPTIONS: html-style:nil
@end example


For longer style definitions, either use several @samp{HTML_HEAD} and
@samp{HTML_HEAD_EXTRA} keywords, or use @code{<style> ... </style>} blocks
around them.  Both of these approaches can avoid referring to an
external file.

@cindex @samp{HTML_CONTAINER_CLASS}, property
@cindex @samp{HTML_HEADLINE_CLASS}, property
In order to add styles to a sub-tree, use the @samp{HTML_CONTAINER_CLASS}
property to assign a class to the tree.  In order to specify CSS
styles for a particular headline, you can use the ID specified in
a @samp{CUSTOM_ID} property.  You can also assign a specific class to
a headline with the @samp{HTML_HEADLINE_CLASS} property.

Never change the @code{org-html-style-default} constant.  Instead use other
simpler ways of customizing as described above.

@node JavaScript support
@subsection JavaScript supported display of web pages

Sebastian Rose has written a JavaScript program especially designed to
enhance the web viewing experience of HTML files created with Org.
This program enhances large files in two different ways of viewing.
One is an @emph{Info}-like mode where each section is displayed separately
and navigation can be done with the @kbd{n} and @kbd{p}
keys, and some other keys as well, press @kbd{?} for an overview
of the available keys.  The second one has a @emph{folding} view, much like
Org provides inside Emacs.  The script is available at
@uref{https://orgmode.org/org-info.js} and the documentation at
@uref{https://orgmode.org/worg/code/org-info-js/}.  The script is hosted on
@uref{https://orgmode.org}, but for reliability, prefer installing it on your
own web server.

To use this program, just add this line to the Org file:

@cindex @samp{INFOJS_OPT}, keyword
@example
#+INFOJS_OPT: view:info toc:nil
@end example


@noindent
The HTML header now has the code needed to automatically invoke the
script.  For setting options, use the syntax from the above line for
options described below:

@table @asis
@item @samp{path:}
The path to the script.  The default is to grab the script from
@uref{https://orgmode.org/org-info.js}, but you might want to have a local
copy and use a path like @samp{../scripts/org-info.js}.

@item @samp{view:}
Initial view when the website is first shown.  Possible values are:

@multitable {aaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{info}
@tab Info-like interface with one section per page
@item @samp{overview}
@tab Folding interface, initially showing only top-level
@item @samp{content}
@tab Folding interface, starting with all headlines visible
@item @samp{showall}
@tab Folding interface, all headlines and text visible
@end multitable

@item @samp{sdepth:}
Maximum headline level still considered as an independent section
for info and folding modes.  The default is taken from
@code{org-export-headline-levels}, i.e., the @samp{H} switch in @samp{OPTIONS}.  If
this is smaller than in @code{org-export-headline-levels}, each
info/folding section can still contain child headlines.

@item @samp{toc:}
Should the table of contents @emph{initially} be visible?  Even when
@samp{nil}, you can always get to the ``toc'' with @kbd{i}.

@item @samp{tdepth:}
The depth of the table of contents.  The defaults are taken from the
variables @code{org-export-headline-levels} and @code{org-export-with-toc}.

@item @samp{ftoc:}
Does the CSS of the page specify a fixed position for the ``toc''?  If
yes, the toc is displayed as a section.

@item @samp{ltoc:}
Should there be short contents (children) in each section?  Make
this @samp{above} if the section should be above initial text.

@item @samp{mouse:}
Headings are highlighted when the mouse is over them.  Should be
@samp{underline} (default) or a background color like @samp{#cccccc}.

@item @samp{buttons:}
Should view-toggle buttons be everywhere?  When @samp{nil} (the default),
only one such button is present.
@end table

@vindex org-infojs-options
@vindex org-export-html-use-infojs
You can choose default values for these options by customizing the
variable @code{org-infojs-options}.  If you always want to apply the script
to your pages, configure the variable @code{org-export-html-use-infojs}.

@node @LaTeX{} Export
@section @LaTeX{} Export

@cindex @LaTeX{} export
@cindex PDF export

The @LaTeX{} export back-end can handle complex documents, incorporate
standard or custom @LaTeX{} document classes, generate documents using
alternate @LaTeX{} engines, and produce fully linked PDF files with
indexes, bibliographies, and tables of contents, destined for
interactive online viewing or high-quality print publication.

While the details are covered in-depth in this section, here are some
quick references to variables for the impatient: for engines, see
@code{org-latex-compiler}; for build sequences, see
@code{org-latex-pdf-process}; for packages, see
@code{org-latex-default-packages-alist} and @code{org-latex-packages-alist}.

An important note about the @LaTeX{} export back-end: it is sensitive to
blank lines in the Org document.  That's because @LaTeX{} itself depends
on blank lines to tell apart syntactical elements, such as paragraphs.

@menu
* @LaTeX{}/PDF export commands:: For producing @LaTeX{} and PDF documents.
* @LaTeX{} specific export settings:: Unique to this @LaTeX{} back-end.
* @LaTeX{} header and sectioning:: Setting up the export file structure.
* Quoting @LaTeX{} code::        Incorporating literal @LaTeX{} code.
* Tables in @LaTeX{} export::    Options for exporting tables to @LaTeX{}.
* Images in @LaTeX{} export::    How to insert figures into @LaTeX{} output.
* Plain lists in @LaTeX{} export:: Attributes specific to lists.
* Source blocks in @LaTeX{} export:: Attributes specific to source code blocks.
* Example blocks in @LaTeX{} export:: Attributes specific to example blocks.
* Special blocks in @LaTeX{} export:: Attributes specific to special blocks.
* Horizontal rules in @LaTeX{} export:: Attributes specific to horizontal rules.
@end menu

@node @LaTeX{}/PDF export commands
@subsection @LaTeX{}/PDF export commands

@table @asis
@item @kbd{C-c C-e l l} (@code{org-latex-export-to-latex})
@kindex C-c C-e l l
@findex org-latex-export-to-latex~
Export to a @LaTeX{} file with a @samp{.tex} extension.  For @samp{myfile.org},
Org exports to @samp{myfile.tex}, overwriting without warning.

@item @kbd{C-c C-e l L} (@code{org-latex-export-as-latex})
@kindex C-c C-e l L
@findex org-latex-export-as-latex
Export to a temporary buffer.  Do not create a file.

@item @kbd{C-c C-e l p} (@code{org-latex-export-to-pdf})
@kindex C-c C-e l p
@findex org-latex-export-to-pdf
Export as @LaTeX{} file and convert it to PDF file.

@item @kbd{C-c C-e l o}
@kindex C-c C-e l o
Export as @LaTeX{} file and convert it to PDF, then open the PDF using
the default viewer.

@item @kbd{M-x org-export-region-as-latex}
Convert the region to @LaTeX{} under the assumption that it was in Org
mode syntax before.  This is a global command that can be invoked in
any buffer.
@end table

@vindex org-latex-compiler
@vindex org-latex-bibtex-compiler
@vindex org-latex-default-packages-alist
@cindex pdflatex
@cindex xelatex
@cindex lualatex
@cindex @samp{LATEX_COMPILER}, keyword
The @LaTeX{} export back-end can use any of these @LaTeX{} engines:
@samp{pdflatex}, @samp{xelatex}, and @samp{lualatex}.  These engines compile @LaTeX{}
files with different compilers, packages, and output options.  The
@LaTeX{} export back-end finds the compiler version to use from
@code{org-latex-compiler} variable or the @samp{#+LATEX_COMPILER} keyword in the
Org file.  See the docstring for the
@code{org-latex-default-packages-alist} for loading packages with certain
compilers.  Also see @code{org-latex-bibtex-compiler} to set the
bibliography compiler@footnote{This does not allow setting different bibliography compilers
for different files.  However, ``smart'' @LaTeX{} compilation systems, such
as latexmk, can select the correct bibliography compiler.}.

@node @LaTeX{} specific export settings
@subsection @LaTeX{} specific export settings

The @LaTeX{} export back-end has several additional keywords for
customizing @LaTeX{} output.  Setting these keywords works similar to the
general options (see @ref{Export Settings}).

@table @asis
@item @samp{DESCRIPTION}
@cindex @samp{DESCRIPTION}, keyword
@vindex org-latex-hyperref-template
@vindex org-latex-title-command
The document's description.  The description along with author name,
keywords, and related file metadata are inserted in the output file
by the hyperref package.  See @code{org-latex-hyperref-template} for
customizing metadata items.  See @code{org-latex-title-command} for
typesetting description into the document's front matter.  Use
multiple @samp{DESCRIPTION} keywords for long descriptions.

@item @samp{LANGUAGE}
@cindex @samp{LANGUAGE}, keyword
@vindex org-latex-packages-alist
In order to be effective, the @samp{babel} or @samp{polyglossia}
packages---according to the @LaTeX{} compiler used---must be loaded
with the appropriate language as argument.  This can be accomplished
by modifying the @code{org-latex-packages-alist} variable, e.g., with the
following snippet:

@lisp
(add-to-list 'org-latex-packages-alist
             '("AUTO" "babel" t ("pdflatex")))
(add-to-list 'org-latex-packages-alist
             '("AUTO" "polyglossia" t ("xelatex" "lualatex")))
@end lisp

@item @samp{LATEX_CLASS}
@cindex @samp{LATEX_CLASS}, keyword
@vindex org-latex-default-class
@vindex org-latex-classes
This is @LaTeX{} document class, such as @emph{article}, @emph{report}, @emph{book},
and so on, which contain predefined preamble and headline level
mapping that the @LaTeX{} export back-end needs.  The back-end reads
the default class name from the @code{org-latex-default-class} variable.
Org has @emph{article} as the default class.  A valid default class must
be an element of @code{org-latex-classes}.

@item @samp{LATEX_CLASS_OPTIONS}
@cindex @samp{LATEX_CLASS_OPTIONS}, keyword
Options the @LaTeX{} export back-end uses when calling the @LaTeX{}
document class.

@item @samp{LATEX_COMPILER}
@cindex @samp{LATEX_COMPILER}, keyword
@vindex org-latex-compiler
The compiler, such as @samp{pdflatex}, @samp{xelatex}, @samp{lualatex}, for
producing the PDF@.  See @code{org-latex-compiler}.

@item @samp{LATEX_HEADER}
@itemx @samp{LATEX_HEADER_EXTRA}
@cindex @samp{LATEX_HEADER}, keyword
@cindex @samp{LATEX_HEADER_EXTRA}, keyword
@vindex org-latex-classes
Arbitrary lines to add to the document's preamble, before the
hyperref settings.  See @code{org-latex-classes} for adjusting the
structure and order of the @LaTeX{} headers.

@item @samp{KEYWORDS}
@cindex @samp{KEYWORDS}, keyword
@vindex org-latex-hyperref-template
@vindex org-latex-title-command
The keywords for the document.  The description along with author
name, keywords, and related file metadata are inserted in the output
file by the hyperref package.  See @code{org-latex-hyperref-template} for
customizing metadata items.  See @code{org-latex-title-command} for
typesetting description into the document's front matter.  Use
multiple @samp{KEYWORDS} lines if necessary.

@item @samp{SUBTITLE}
@cindex @samp{SUBTITLE}, keyword
@vindex org-latex-subtitle-separate
@vindex org-latex-subtitle-format
The document's subtitle.  It is typeset as per
@code{org-latex-subtitle-format}.  If @code{org-latex-subtitle-separate} is
non-@code{nil}, it is typed outside of the @code{\title} macro.  See
@code{org-latex-hyperref-template} for customizing metadata items.  See
@code{org-latex-title-command} for typesetting description into the
document's front matter.
@end table

The following sections have further details.

@node @LaTeX{} header and sectioning
@subsection @LaTeX{} header and sectioning structure

@cindex @LaTeX{} class
@cindex @LaTeX{} sectioning structure
@cindex @LaTeX{} header
@cindex header, for @LaTeX{} files
@cindex sectioning structure, for @LaTeX{} export

The @LaTeX{} export back-end converts the first three of Org's outline
levels into @LaTeX{} headlines.  The remaining Org levels are exported as
lists.  To change this globally for the cut-off point between levels
and lists, (see @ref{Export Settings}).

By default, the @LaTeX{} export back-end uses the @emph{article} class.

@vindex org-latex-default-class
@vindex org-latex-classes
@vindex org-latex-default-packages-alist
@vindex org-latex-packages-alist
To change the default class globally, edit @code{org-latex-default-class}.
To change the default class locally in an Org file, add option lines
@samp{#+LATEX_CLASS: myclass}.  To change the default class for just a part
of the Org file, set a sub-tree property, @samp{EXPORT_LATEX_CLASS}.  The
class name entered here must be valid member of @code{org-latex-classes}.
This variable defines a header template for each class into which the
exporter splices the values of @code{org-latex-default-packages-alist} and
@code{org-latex-packages-alist}.  Use the same three variables to define
custom sectioning or custom classes.

@cindex @samp{LATEX_CLASS}, keyword
@cindex @samp{LATEX_CLASS_OPTIONS}, keyword
@cindex @samp{EXPORT_LATEX_CLASS}, property
@cindex @samp{EXPORT_LATEX_CLASS_OPTIONS}, property
The @LaTeX{} export back-end sends the @samp{LATEX_CLASS_OPTIONS} keyword and
@samp{EXPORT_LATEX_CLASS_OPTIONS} property as options to the @LaTeX{}
@code{\documentclass} macro.  The options and the syntax for specifying
them, including enclosing them in square brackets, follow @LaTeX{}
conventions.

@example
#+LATEX_CLASS_OPTIONS: [a4paper,11pt,twoside,twocolumn]
@end example


@cindex @samp{LATEX_HEADER}, keyword
@cindex @samp{LATEX_HEADER_EXTRA}, keyword
The @LaTeX{} export back-end appends values from @samp{LATEX_HEADER} and
@samp{LATEX_HEADER_EXTRA} keywords to the @LaTeX{} header.  The docstring for
@code{org-latex-classes} explains in more detail.  Also note that @LaTeX{}
export back-end does not append @samp{LATEX_HEADER_EXTRA} to the header
when previewing @LaTeX{} snippets (see @ref{Previewing @LaTeX{} fragments}).

A sample Org file with the above headers:

@example
#+LATEX_CLASS: article
#+LATEX_CLASS_OPTIONS: [a4paper]
#+LATEX_HEADER: \usepackage@{xyz@}

* Headline 1
  some text
* Headline 2
  some more text
@end example

@node Quoting @LaTeX{} code
@subsection Quoting @LaTeX{} code

The @LaTeX{} export back-end can insert any arbitrary @LaTeX{} code, see
@ref{Embedded @LaTeX{}}.  There are three ways to embed such code in the Org
file and they all use different quoting syntax.

@cindex inline, in @LaTeX{} export
Inserting in-line quoted with @@ symbols:

@example
Code embedded in-line @@@@latex:any arbitrary LaTeX code@@@@ in a paragraph.
@end example


@cindex @samp{LATEX}, keyword
Inserting as one or more keyword lines in the Org file:

@example
#+LATEX: any arbitrary LaTeX code
@end example


@cindex @samp{BEGIN_EXPORT latex}
Inserting as an export block in the Org file, where the back-end
exports any code between begin and end markers:

@example
#+BEGIN_EXPORT latex
  any arbitrary LaTeX code
#+END_EXPORT
@end example

@node Tables in @LaTeX{} export
@subsection Tables in @LaTeX{} export

@cindex tables, in @LaTeX{} export

The @LaTeX{} export back-end can pass several @LaTeX{} attributes for table
contents and layout.  Besides specifying a label (see @ref{Internal Links})
and a caption (see @ref{Captions}), the other valid @LaTeX{} attributes
include:

@table @asis
@item @samp{:mode}
@vindex org-latex-default-table-mode
The @LaTeX{} export back-end wraps the table differently depending on
the mode for accurate rendering of math symbols.  Mode is either
@samp{table}, @samp{math}, @samp{inline-math} or @samp{verbatim}.

For @samp{math} or @samp{inline-math} mode, @LaTeX{} export back-end wraps the
table in a math environment, but every cell in it is exported as-is.
The @LaTeX{} export back-end determines the default mode from
@code{org-latex-default-table-mode}.  The @LaTeX{} export back-end merges
contiguous tables in the same mode into a single environment.

@item @samp{:environment}
@vindex org-latex-default-table-environment
Set the default @LaTeX{} table environment for the @LaTeX{} export
back-end to use when exporting Org tables.  Common @LaTeX{} table
environments are provided by these packages: tabularx, longtable,
array, tabu, and bmatrix.  For packages, such as tabularx and tabu,
or any newer replacements, include them in the
@code{org-latex-packages-alist} variable so the @LaTeX{} export back-end can
insert the appropriate load package headers in the converted @LaTeX{}
file.  Look in the docstring for the @code{org-latex-packages-alist}
variable for configuring these packages for @LaTeX{} snippet previews,
if any.

@item @samp{:caption}
Use @samp{CAPTION} keyword to set a simple caption for a table (see
@ref{Captions}).  For custom captions, use @samp{:caption} attribute, which
accepts raw @LaTeX{} code.  @samp{:caption} value overrides @samp{CAPTION} value.

@item @samp{:float}
@itemx @samp{:placement}
The table environments by default are not floats in @LaTeX{}.  To make
them floating objects use @samp{:float} with one of the following
options: @samp{sideways}, @samp{multicolumn}, @samp{t}, and @samp{nil}.

@LaTeX{} floats can also have additional layout @samp{:placement}
attributes.  These are the usual @samp{[h t b p ! H]} permissions
specified in square brackets.  Note that for @samp{:float sideways}
tables, the @LaTeX{} export back-end ignores @samp{:placement} attributes.

@item @samp{:align}
@itemx @samp{:font}
@itemx @samp{:width}
The @LaTeX{} export back-end uses these attributes for regular tables
to set their alignments, fonts, and widths.

@item @samp{:spread}
When @samp{:spread} is non-@code{nil}, the @LaTeX{} export back-end spreads or
shrinks the table by the @samp{:width} for tabu and longtabu
environments.  @samp{:spread} has no effect if @samp{:width} is not set.

@item @samp{:booktabs}
@itemx @samp{:center}
@itemx @samp{:rmlines}
@vindex org-latex-tables-booktabs
@vindex org-latex-tables-centered
All three commands are toggles.  @samp{:booktabs} brings in modern
typesetting enhancements to regular tables.  The booktabs package
has to be loaded through @code{org-latex-packages-alist}.  @samp{:center} is
for centering the table.  @samp{:rmlines} removes all but the very first
horizontal line made of ASCII characters from ``table.el'' tables
only.

@item @samp{:math-prefix}
@itemx @samp{:math-suffix}
@itemx @samp{:math-arguments}
The @LaTeX{} export back-end inserts @samp{:math-prefix} string value in
a math environment before the table.  The @LaTeX{} export back-end
inserts @samp{:math-suffix} string value in a math environment after the
table.  The @LaTeX{} export back-end inserts @samp{:math-arguments} string
value between the macro name and the table's contents.
@samp{:math-arguments} comes in use for matrix macros that require more
than one argument, such as @samp{qbordermatrix}.
@end table

@LaTeX{} table attributes help formatting tables for a wide range of
situations, such as matrix product or spanning multiple pages:

@example
#+ATTR_LATEX: :environment longtable :align l|lp@{3cm@}r|l
| ... | ... |
| ... | ... |

#+ATTR_LATEX: :mode math :environment bmatrix :math-suffix \times
| a | b |
| c | d |
#+ATTR_LATEX: :mode math :environment bmatrix
| 1 | 2 |
| 3 | 4 |
@end example

Set the caption with the @LaTeX{} command
@samp{\bicaption@{HeadingA@}@{HeadingB@}}:

@example
#+ATTR_LATEX: :caption \bicaption@{HeadingA@}@{HeadingB@}
| ... | ... |
| ... | ... |
@end example

@node Images in @LaTeX{} export
@subsection Images in @LaTeX{} export

@cindex images, inline in LaTeX
@cindex inlining images in LaTeX
@cindex @samp{ATTR_LATEX}, keyword

The @LaTeX{} export back-end processes image links in Org files that do
not have descriptions, such as these links @samp{[[file:img.jpg]]} or
@samp{[[./img.jpg]]}, as direct image insertions in the final PDF output.  In
the PDF, they are no longer links but actual images embedded on the
page.  The @LaTeX{} export back-end uses @samp{\includegraphics} macro to
insert the image.  But for TikZ (@uref{http://sourceforge.net/projects/pgf/})
images, the back-end uses an @code{\input} macro wrapped within
a @code{tikzpicture} environment.

For specifying image @samp{:width}, @samp{:height}, @samp{:scale} and other @samp{:options},
use this syntax:

@example
#+ATTR_LATEX: :width 5cm :options angle=90
[[./img/sed-hr4049.pdf]]
@end example

A @samp{:scale} attribute overrides both @samp{:width} and @samp{:height} attributes.

For custom commands for captions, use the @samp{:caption} attribute.  It
overrides the default @samp{#+CAPTION} value:

@example
#+ATTR_LATEX: :caption \bicaption@{HeadingA@}@{HeadingB@}
[[./img/sed-hr4049.pdf]]
@end example

When captions follow the method as described in @ref{Captions}, the @LaTeX{}
export back-end wraps the picture in a floating @samp{figure} environment.
To float an image without specifying a caption, set the @samp{:float}
attribute to one of the following:

@table @asis
@item @samp{t}
For a standard @samp{figure} environment; used by default whenever an
image has a caption.

@item @samp{multicolumn}
To span the image across multiple columns of a page; the back-end
wraps the image in a @samp{figure*} environment.

@item @samp{wrap}
For text to flow around the image on the right; the figure occupies
the left half of the page.

@item @samp{sideways}
For a new page with the image sideways, rotated ninety degrees, in
a @samp{sidewaysfigure} environment; overrides @samp{:placement} setting.

@item @samp{nil}
To avoid a @samp{:float} even if using a caption.
@end table

Use the @samp{placement} attribute to modify a floating environment's
placement.

@example
#+ATTR_LATEX: :float wrap :width 0.38\textwidth :placement @{r@}@{0.4\textwidth@}
[[./img/hst.png]]
@end example

@vindex org-latex-images-centered
@cindex center image in LaTeX export
@cindex image, centering in LaTeX export
The @LaTeX{} export back-end centers all images by default.  Setting
@samp{:center} to @samp{nil} disables centering.  To disable centering globally,
set @code{org-latex-images-centered} to @samp{t}.

Set the @samp{:comment-include} attribute to non-@code{nil} value for the @LaTeX{}
export back-end to comment out the @samp{\includegraphics} macro.

@node Plain lists in @LaTeX{} export
@subsection Plain lists in @LaTeX{} export

@cindex plain lists, in @LaTeX{} export
@cindex @samp{ATTR_LATEX}, keyword
The @LaTeX{} export back-end accepts the @samp{environment} and @samp{options}
attributes for plain lists.  Both attributes work together for
customizing lists, as shown in the examples:

@example
#+LATEX_HEADER: \usepackage[inline]@{enumitem@}
Some ways to say "Hello":
#+ATTR_LATEX: :environment itemize*
#+ATTR_LATEX: :options [label=@{@}, itemjoin=@{,@}, itemjoin*=@{, and@}]
- Hola
- Bonjour
- Guten Tag.
@end example

Since @LaTeX{} supports only four levels of nesting for lists, use an
external package, such as @samp{enumitem} in @LaTeX{}, for levels deeper than
four:

@example
#+LATEX_HEADER: \usepackage@{enumitem@}
#+LATEX_HEADER: \renewlist@{itemize@}@{itemize@}@{9@}
#+LATEX_HEADER: \setlist[itemize]@{label=$\circ$@}
- One
  - Two
    - Three
      - Four
        - Five
@end example

@node Source blocks in @LaTeX{} export
@subsection Source blocks in @LaTeX{} export

@cindex source blocks, in @LaTeX{} export
@cindex @samp{ATTR_LATEX}, keyword

The @LaTeX{} export back-end can make source code blocks into floating
objects through the attributes @samp{:float} and @samp{:options}.  For @samp{:float}:

@table @asis
@item @samp{t}
Makes a source block float; by default floats any source block with
a caption.

@item @samp{multicolumn}
Spans the source block across multiple columns of a page.

@item @samp{nil}
Avoids a @samp{:float} even if using a caption; useful for source code
blocks that may not fit on a page.
@end table

@example
#+ATTR_LATEX: :float nil
#+BEGIN_SRC emacs-lisp
  Lisp code that may not fit in a single page.
#+END_SRC
@end example

@vindex org-latex-listings-options
@vindex org-latex-minted-options
The @LaTeX{} export back-end passes string values in @samp{:options} to @LaTeX{}
packages for customization of that specific source block.  In the
example below, the @samp{:options} are set for Minted.  Minted is a source
code highlighting @LaTeX{} package with many configurable options.

@example
#+ATTR_LATEX: :options commentstyle=\bfseries
#+BEGIN_SRC emacs-lisp
  (defun Fib (n)
    (if (< n 2) n (+ (Fib (- n 1)) (Fib (- n 2)))))
#+END_SRC
@end example

To apply similar configuration options for all source blocks in
a file, use the @code{org-latex-listings-options} and
@code{org-latex-minted-options} variables.

@node Example blocks in @LaTeX{} export
@subsection Example blocks in @LaTeX{} export

@cindex example blocks, in @LaTeX{} export
@cindex verbatim blocks, in @LaTeX{} export
@cindex @samp{ATTR_LATEX}, keyword

The @LaTeX{} export back-end wraps the contents of example blocks in
a @samp{verbatim} environment.  To change this behavior to use another
environment globally, specify an appropriate export filter (see
@ref{Advanced Export Configuration}).  To change this behavior to use
another environment for each block, use the @samp{:environment} parameter
to specify a custom environment.

@example
#+ATTR_LATEX: :environment myverbatim
#+BEGIN_EXAMPLE
  This sentence is false.
#+END_EXAMPLE
@end example

@node Special blocks in @LaTeX{} export
@subsection Special blocks in @LaTeX{} export

@cindex special blocks, in @LaTeX{} export
@cindex abstract, in @LaTeX{} export
@cindex proof, in @LaTeX{} export
@cindex @samp{ATTR_LATEX}, keyword

For other special blocks in the Org file, the @LaTeX{} export back-end
makes a special environment of the same name.  The back-end also takes
@samp{:options}, if any, and appends as-is to that environment's opening
string.  For example:

@example
#+BEGIN_abstract
  We demonstrate how to solve the Syracuse problem.
#+END_abstract

#+ATTR_LATEX: :options [Proof of important theorem]
#+BEGIN_proof
  ...
  Therefore, any even number greater than 2 is the sum of two primes.
#+END_proof
@end example

@noindent
exports to

@example
\begin@{abstract@}
  We demonstrate how to solve the Syracuse problem.
\end@{abstract@}

\begin@{proof@}[Proof of important theorem]
  ...
  Therefore, any even number greater than 2 is the sum of two primes.
\end@{proof@}
@end example

If you need to insert a specific caption command, use @samp{:caption}
attribute.  It overrides standard @samp{CAPTION} value, if any.  For
example:

@example
#+ATTR_LATEX: :caption \MyCaption@{HeadingA@}
#+BEGIN_proof
  ...
#+END_proof
@end example

@node Horizontal rules in @LaTeX{} export
@subsection Horizontal rules in @LaTeX{} export

@cindex horizontal rules, in @LaTeX{} export
@cindex @samp{ATTR_LATEX}, keyword

The @LaTeX{} export back-end converts horizontal rules by the specified
@samp{:width} and @samp{:thickness} attributes.  For example:

@example
#+ATTR_LATEX: :width .6\textwidth :thickness 0.8pt
-----
@end example

@node Markdown Export
@section Markdown Export

@cindex Markdown export

The Markdown export back-end, ``md'', converts an Org file to Markdown
format, as defined at @uref{http://daringfireball.net/projects/markdown/}.

Since it is built on top of the HTML back-end (see @ref{HTML Export}), it
converts every Org construct not defined in Markdown syntax, such as
tables, to HTML@.

@anchor{Markdown export commands}
@subheading Markdown export commands

@table @asis
@item @kbd{C-c C-e m m} (@code{org-md-export-to-markdown})
@kindex C-c C-c m m
@findex org-md-export-to-markdown
Export to a text file with Markdown syntax.  For @samp{myfile.org}, Org
exports to @samp{myfile.md}, overwritten without warning.

@item @kbd{C-c C-e m M} (@code{org-md-export-as-markdown})
@kindex C-c C-c m M
@findex org-md-export-as-markdown
Export to a temporary buffer.  Does not create a file.

@item @kbd{C-c C-e m o}
@kindex C-c C-e m o
Export as a text file with Markdown syntax, then open it.
@end table

@anchor{Header and sectioning structure (1)}
@subheading Header and sectioning structure

@vindex org-md-headline-style
Based on @code{org-md-headline-style}, Markdown export can generate
headlines of both @emph{atx} and @emph{setext} types.  @emph{atx} limits headline
levels to two whereas @emph{setext} limits headline levels to six.  Beyond
these limits, the export back-end converts headlines to lists.  To set
a limit to a level before the absolute limit (see @ref{Export Settings}).

@node OpenDocument Text Export
@section OpenDocument Text Export

@cindex ODT
@cindex OpenDocument
@cindex export, OpenDocument
@cindex LibreOffice

The ODT export back-end handles creating of OpenDocument Text (ODT)
format.  Documents created by this exporter use the
@cite{OpenDocument-v1.2 specification}@footnote{See @uref{http://docs.oasis-open.org/office/v1.2/OpenDocument-v1.2.html, Open Document Format for Office Applications
(OpenDocument) Version 1.2}.} and are compatible
with LibreOffice 3.4.

@menu
* Pre-requisites for ODT export:: Required packages.
* ODT export commands::          Invoking export.
* ODT specific export settings:: Configuration options.
* Extending ODT export::         Producing DOC, PDF files.
* Applying custom styles::       Styling the output.
* Links in ODT export::          Handling and formatting links.
* Tables in ODT export::         Org tables conversions.
* Images in ODT export::         Inserting images.
* Math formatting in ODT export:: Formatting @LaTeX{} fragments.
* Labels and captions in ODT export:: Rendering objects.
* Literal examples in ODT export:: For source code and example blocks.
* Advanced topics in ODT export:: For power users.
@end menu

@node Pre-requisites for ODT export
@subsection Pre-requisites for ODT export

@cindex zip

The ODT export back-end relies on the zip program to create the final
compressed ODT output.  Check if @samp{zip} is locally available and
executable.  Without it, export cannot finish.

@node ODT export commands
@subsection ODT export commands

@table @asis
@item @kbd{C-c C-e o o} (@code{org-export-to-odt})
@kindex C-c C-e o o
@findex org-export-to-odt
Export as OpenDocument Text file.

@cindex @samp{EXPORT_FILE_NAME}, property
@vindex org-odt-preferred-output-format

If @code{org-odt-preferred-output-format} is specified, the ODT export
back-end automatically converts the exported file to that format.

For @samp{myfile.org}, Org exports to @samp{myfile.odt}, overwriting without
warning.  The ODT export back-end exports a region only if a region
was active.

If the selected region is a single tree, the ODT export back-end
makes the tree head the document title.  Incidentally, @kbd{C-c @@} selects the current sub-tree.  If the tree head entry has, or
inherits, an @samp{EXPORT_FILE_NAME} property, the ODT export back-end
uses that for file name.

@item @kbd{C-c C-e o O}
@kindex C-c C-e o O
Export as an OpenDocument Text file and open the resulting file.

@vindex org-export-odt-preferred-output-format
If @code{org-export-odt-preferred-output-format} is specified, open the
converted file instead.  See @ref{Automatically exporting to other formats}.
@end table

@node ODT specific export settings
@subsection ODT specific export settings

The ODT export back-end has several additional keywords for
customizing ODT output.  Setting these keywords works similar to the
general options (see @ref{Export Settings}).

@table @asis
@item @samp{DESCRIPTION}
@cindex @samp{DESCRIPTION}, keyword
This is the document's description, which the ODT export back-end
inserts as document metadata.  For long descriptions, use multiple
lines, prefixed with @samp{DESCRIPTION}.

@item @samp{KEYWORDS}
@cindex @samp{KEYWORDS}, keyword
The keywords for the document.  The ODT export back-end inserts the
description along with author name, keywords, and related file
metadata as metadata in the output file.  Use multiple @samp{KEYWORDS} if
necessary.

@item @samp{ODT_STYLES_FILE}
@cindex @samp{ODT_STYLES_FILE}, keyword
@vindex org-odt-styles-file
The ODT export back-end uses the @code{org-odt-styles-file} by default.
See @ref{Applying custom styles} for details.

@item @samp{SUBTITLE}
@cindex @samp{SUBTITLE}, keyword
The document subtitle.
@end table

@node Extending ODT export
@subsection Extending ODT export

The ODT export back-end can produce documents in other formats besides
ODT using a specialized ODT converter process.  Its common interface
works with popular converters to produce formats such as @samp{doc}, or
convert a document from one format, say @samp{csv}, to another format, say
@samp{xls}.

@cindex @file{unoconv}
@vindex org-odt-convert-process
Customize @code{org-odt-convert-process} variable to point to @samp{unoconv},
which is the ODT's preferred converter.  Working installations of
LibreOffice would already have @samp{unoconv} installed.  Alternatively,
other converters may be substituted here.  See @ref{Configuring a document converter}.

@anchor{Automatically exporting to other formats}
@subsubheading Automatically exporting to other formats

@vindex org-odt-preferred-output-format
If ODT format is just an intermediate step to get to other formats,
such as @samp{doc}, @samp{docx}, @samp{rtf}, or @samp{pdf}, etc., then extend the ODT
export back-end to directly produce that format.  Specify the final
format in the @code{org-odt-preferred-output-format} variable.  This is one
way to extend (see @ref{ODT export commands}).

@anchor{Converting between document formats}
@subsubheading Converting between document formats

The Org export back-end is made to be inter-operable with a wide range
of text document format converters.  Newer generation converters, such
as LibreOffice and Pandoc, can handle hundreds of formats at once.
Org provides a consistent interaction with whatever converter is
installed.  Here are some generic commands:

@table @asis
@item @kbd{M-x org-odt-convert}
@findex org-odt-convert
Convert an existing document from one format to another.  With
a prefix argument, opens the newly produced file.
@end table

@node Applying custom styles
@subsection Applying custom styles

@cindex styles, custom
@cindex template, custom

The ODT export back-end comes with many OpenDocument styles (see
@ref{Working with OpenDocument style files}).  To expand or further
customize these built-in style sheets, either edit the style sheets
directly or generate them using an application such as LibreOffice.
The example here shows creating a style using LibreOffice.

@anchor{Applying custom styles the easy way}
@subsubheading Applying custom styles: the easy way

@enumerate
@item
Create a sample @samp{example.org} file with settings as shown below,
and export it to ODT format.

@example
#+OPTIONS: H:10 num:t
@end example

@item
Open the above @samp{example.odt} using LibreOffice.  Use the @emph{Stylist}
to locate the target styles, which typically have the ``Org'' prefix.
Open one, modify, and save as either OpenDocument Text (ODT) or
OpenDocument Template (OTT) file.

@item
@vindex org-odt-styles-file
Customize the variable @code{org-odt-styles-file} and point it to the
newly created file.  For additional configuration options, see
@ref{x-overriding-factory-styles, , Overriding factory styles}.

@cindex @samp{ODT_STYLES_FILE}, keyword
To apply an ODT style to a particular file, use the
@samp{ODT_STYLES_FILE} keyword as shown in the example below:

@example
#+ODT_STYLES_FILE: "/path/to/example.ott"
@end example


@noindent
or

@example
#+ODT_STYLES_FILE: ("/path/to/file.ott" ("styles.xml" "image/hdr.png"))
@end example
@end enumerate

@anchor{Using third-party styles and templates}
@subsubheading Using third-party styles and templates

The ODT export back-end relies on many templates and style names.
Using third-party styles and templates can lead to mismatches.
Templates derived from built in ODT templates and styles seem to have
fewer problems.

@node Links in ODT export
@subsection Links in ODT export

@cindex links, in ODT export

ODT exporter creates native cross-references for internal links.  It
creates Internet-style links for all other links.

A link with no description and pointing to a regular, un-itemized,
outline heading is replaced with a cross-reference and section number
of the heading.

A @samp{\ref@{label@}}-style reference to an image, table etc., is replaced
with a cross-reference and sequence number of the labeled entity.  See
@ref{Labels and captions in ODT export}.

@node Tables in ODT export
@subsection Tables in ODT export

@cindex tables, in ODT export

The ODT export back-end handles native Org mode tables (see @ref{Tables})
and simple @samp{table.el} tables.  Complex @samp{table.el} tables having column
or row spans are not supported.  Such tables are stripped from the
exported document.

By default, the ODT export back-end exports a table with top and
bottom frames and with ruled lines separating row and column groups
(see @ref{Column Groups}).  All tables are typeset to occupy the same
width.  The ODT export back-end honors any table alignments and
relative widths for columns (see @ref{Column Width and Alignment}).

Note that the ODT export back-end interprets column widths as weighted
ratios, the default weight being 1.

@cindex @samp{ATTR_ODT}, keyword
Specifying @samp{:rel-width} property on an @samp{ATTR_ODT} line controls the
width of the table.  For example:

@example
#+ATTR_ODT: :rel-width 50
| Area/Month    |   Jan |   Feb |   Mar |   Sum |
|---------------+-------+-------+-------+-------|
| /             |     < |       |       |     < |
| <l13>         |  <r5> |  <r5> |  <r5> |  <r6> |
| North America |     1 |    21 |   926 |   948 |
| Middle East   |     6 |    75 |   844 |   925 |
| Asia Pacific  |     9 |    27 |   790 |   826 |
|---------------+-------+-------+-------+-------|
| Sum           |    16 |   123 |  2560 |  2699 |
@end example

On export, the above table takes 50% of text width area.  The exporter
sizes the columns in the ratio: 13:5:5:5:6.  The first column is
left-aligned and rest of the columns, right-aligned.  Vertical rules
separate the header and the last column.  Horizontal rules separate
the header and the last row.

For even more customization, create custom table styles and associate
them with a table using the @samp{ATTR_ODT} keyword.  See @ref{Customizing tables in ODT export}.

@node Images in ODT export
@subsection Images in ODT export

@cindex images, embedding in ODT
@cindex embedding images in ODT

@anchor{Embedding images}
@subsubheading Embedding images

The ODT export back-end processes image links in Org files that do not
have descriptions, such as these links @samp{[[file:img.jpg]]} or @samp{[[./img.jpg]]},
as direct image insertions in the final output.  Either of these
examples works:

@example
[[file:img.png]]
@end example


@example
[[./img.png]]
@end example

@anchor{Embedding clickable images}
@subsubheading Embedding clickable images

For clickable images, provide a link whose description is another link
to an image file.  For example, to embed an image
@samp{org-mode-unicorn.png} which when clicked jumps to @uref{https://orgmode.org}
website, do the following

@example
[[https://orgmode.org][./org-mode-unicorn.png]]
@end example

@anchor{Sizing and scaling of embedded images}
@subsubheading Sizing and scaling of embedded images

@cindex @samp{ATTR_ODT}, keyword

Control the size and scale of the embedded images with the @samp{ATTR_ODT}
attribute.

@cindex identify, ImageMagick
@vindex org-odt-pixels-per-inch
The ODT export back-end starts with establishing the size of the image
in the final document.  The dimensions of this size are measured in
centimeters.  The back-end then queries the image file for its
dimensions measured in pixels.  For this measurement, the back-end
relies on ImageMagick's identify program or Emacs @code{create-image} and
@code{image-size} API@.  ImageMagick is the preferred choice for large file
sizes or frequent batch operations.  The back-end then converts the
pixel dimensions using @code{org-odt-pixels-per-inch} into the familiar 72
dpi or 96 dpi.  The default value for this is in
@code{display-pixels-per-inch}, which can be tweaked for better results
based on the capabilities of the output device.  Here are some common
image scaling operations:

@table @asis
@item Explicitly size the image
To embed @samp{img.png} as a 10 cm x 10 cm image, do the following:

@example
#+ATTR_ODT: :width 10 :height 10
[[./img.png]]
@end example

@item Scale the image
To embed @samp{img.png} at half its size, do the following:

@example
#+ATTR_ODT: :scale 0.5
[[./img.png]]
@end example

@item Scale the image to a specific width
To embed @samp{img.png} with a width of 10 cm while retaining the
original height:width ratio, do the following:

@example
#+ATTR_ODT: :width 10
[[./img.png]]
@end example

@item Scale the image to a specific height
To embed @samp{img.png} with a height of 10 cm while retaining the
original height:width ratio, do the following:

@example
#+ATTR_ODT: :height 10
[[./img.png]]
@end example
@end table

@anchor{Anchoring of images}
@subsubheading Anchoring of images

@cindex @samp{ATTR_ODT}, keyword
The ODT export back-end can anchor images to @samp{as-char}, @samp{paragraph},
or @samp{page}.  Set the preferred anchor using the @samp{:anchor} property of
the @samp{ATTR_ODT} line.

To create an image that is anchored to a page:

@example
#+ATTR_ODT: :anchor page
[[./img.png]]
@end example

@node Math formatting in ODT export
@subsection Math formatting in ODT export

The ODT exporter has special support for handling math.

@menu
* @LaTeX{} math snippets::       Embedding in @LaTeX{} format.
* MathML and OpenDocument formula files:: Embedding in native format.
@end menu

@node @LaTeX{} math snippets
@subsubsection @LaTeX{} math snippets

@LaTeX{} math snippets (see @ref{@LaTeX{} fragments}) can be embedded in the ODT
document in one of the following ways:

@table @asis
@item MathML
@cindex MathML
Add this line to the Org file.  This option is activated on
a per-file basis.

@example
#+OPTIONS: tex:t
@end example


With this option, @LaTeX{} fragments are first converted into MathML
fragments using an external @LaTeX{}-to-MathML converter program.  The
resulting MathML fragments are then embedded as an OpenDocument
Formula in the exported document.

@vindex org-latex-to-mathml-convert-command
@vindex org-latex-to-mathml-jar-file
You can specify the @LaTeX{}-to-MathML converter by customizing the
variables @code{org-latex-to-mathml-convert-command} and
@code{org-latex-to-mathml-jar-file}.

If you prefer to use MathToWeb@footnote{See @uref{http://www.mathtoweb.com/cgi-bin/mathtoweb_home.pl, MathToWeb}.} as your converter, you can
configure the above variables as shown below.

@lisp
(setq org-latex-to-mathml-convert-command
      "java -jar %j -unicode -force -df %o %I"
      org-latex-to-mathml-jar-file
      "/path/to/mathtoweb.jar")
@end lisp

@noindent
or, to use @LaTeX{}​ML@footnote{See @uref{http://dlmf.nist.gov/LaTeXML/}.} instead,

@lisp
(setq org-latex-to-mathml-convert-command
      "latexmlmath \"%i\" --presentationmathml=%o")
@end lisp

To quickly verify the reliability of the @LaTeX{}-to-MathML
converter, use the following commands:

@table @asis
@item @kbd{M-x org-export-as-odf}
Convert a @LaTeX{} math snippet to an OpenDocument formula (@samp{.odf})
file.

@item @kbd{M-x org-export-as-odf-and-open}
Convert a @LaTeX{} math snippet to an OpenDocument formula (@samp{.odf})
file and open the formula file with the system-registered
application.
@end table

@item PNG images
@cindex dvipng
@cindex dvisvgm
@cindex ImageMagick
Add this line to the Org file.  This option is activated on
a per-file basis.

@example
#+OPTIONS: tex:dvipng
@end example


@example
#+OPTIONS: tex:dvisvgm
@end example


@noindent
or

@example
#+OPTIONS: tex:imagemagick
@end example


Under this option, @LaTeX{} fragments are processed into PNG or SVG
images and the resulting images are embedded in the exported
document.  This method requires dvipng program, dvisvgm or
ImageMagick programs.
@end table

@node MathML and OpenDocument formula files
@subsubsection MathML and OpenDocument formula files

When embedding @LaTeX{} math snippets in ODT documents is not reliable,
there is one more option to try.  Embed an equation by linking to its
MathML (@samp{.mml}) source or its OpenDocument formula (@samp{.odf}) file as
shown below:

@example
[[./equation.mml]]
@end example


@noindent
or

@example
[[./equation.odf]]
@end example

@node Labels and captions in ODT export
@subsection Labels and captions in ODT export

ODT format handles labeling and captioning of objects based on their
types.  Inline images, tables, @LaTeX{} fragments, and Math formulas are
numbered and captioned separately.  Each object also gets a unique
sequence number based on its order of first appearance in the Org
file.  Each category has its own sequence.  A caption is just a label
applied to these objects.

@example
#+CAPTION: Bell curve
#+NAME:   fig:SED-HR4049
[[./img/a.png]]
@end example

When rendered, it may show as follows in the exported document:

@example
Figure 2: Bell curve
@end example


@vindex org-odt-category-map-alist
To modify the category component of the caption, customize the option
@code{org-odt-category-map-alist}.  For example, to tag embedded images
with the string ``Illustration'' instead of the default string ``Figure'',
use the following setting:

@lisp
(setq org-odt-category-map-alist
      '(("__Figure__" "Illustration" "value" "Figure" org-odt--enumerable-image-p)))
@end lisp

With the above modification, the previous example changes to:

@example
Illustration 2: Bell curve
@end example

@node Literal examples in ODT export
@subsection Literal examples in ODT export

The ODT export back-end supports literal examples (see @ref{Literal Examples}) with full fontification.  Internally, the ODT export
back-end relies on @samp{htmlfontify.el} to generate the style definitions
needed for fancy listings.  The auto-generated styles get @samp{OrgSrc}
prefix and inherit colors from the faces used by Emacs Font Lock
library for that source language.

@vindex org-odt-fontify-srcblocks
For custom fontification styles, customize the
@code{org-odt-create-custom-styles-for-srcblocks} option.

@vindex org-odt-create-custom-styles-for-srcblocks
To turn off fontification of literal examples, customize the
@code{org-odt-fontify-srcblocks} option.

@node Advanced topics in ODT export
@subsection Advanced topics in ODT export

The ODT export back-end has extensive features useful for power users
and frequent uses of ODT formats.

@anchor{Configuring a document converter}
@subsubheading Configuring a document converter

@cindex convert
@cindex doc, docx, rtf
@cindex converter

The ODT export back-end works with popular converters with little or
no extra configuration.  See @ref{Extending ODT export}.  The following is
for unsupported converters or tweaking existing defaults.

@table @asis
@item Register the converter
@vindex org-export-odt-convert-processes
Add the name of the converter to the @code{org-odt-convert-processes}
variable.  Note that it also requires how the converter is invoked
on the command line.  See the variable's docstring for details.

@item Configure its capabilities
@vindex org-export-odt-convert-capabilities
Specify which formats the converter can handle by customizing the
variable @code{org-odt-convert-capabilities}.  Use the entry for the
default values in this variable for configuring the new converter.
Also see its docstring for details.

@item Choose the converter
@vindex org-export-odt-convert-process
Select the newly added converter as the preferred one by customizing
the option @code{org-odt-convert-process}.
@end table

@anchor{Working with OpenDocument style files}
@subsubheading Working with OpenDocument style files

@cindex styles, custom
@cindex template, custom

This section explores the internals of the ODT exporter; the means by which
it produces styled documents; the use of automatic and custom OpenDocument
styles.

The ODT exporter relies on two files for generating its output.  These
files are bundled with the distribution under the directory pointed to
by the variable @code{org-odt-styles-dir}.  The two files are:

@table @asis
@item @samp{OrgOdtStyles.xml} @anchor{x-orgodtstyles-xml}
This file contributes to the @samp{styles.xml} file of the final ODT
document.  This file gets modified for the following purposes:

@enumerate
@item
To control outline numbering based on user settings;

@item
To add styles generated by @samp{htmlfontify.el} for fontification of
code blocks.
@end enumerate

@item @samp{OrgOdtContentTemplate.xml} @anchor{x-orgodtcontenttemplate-xml}
This file contributes to the @samp{content.xml} file of the final ODT
document.  The contents of the Org outline are inserted between the
@samp{<office:text>} @dots{} @samp{</office:text>} elements of this file.

Apart from serving as a template file for the final @samp{content.xml},
the file serves the following purposes:

@enumerate
@item
It contains automatic styles for formatting of tables which are
referenced by the exporter;

@item
It contains @samp{<text:sequence-decl>} @dots{} @samp{</text:sequence-decl>}
elements that control numbering of tables, images, equations, and
similar entities.
@end enumerate
@end table

@anchor{x-overriding-factory-styles} The following two variables control
the location from where the ODT exporter picks up the custom styles
and content template files.  Customize these variables to override the
factory styles used by the exporter.

@table @asis
@item @code{org-odt-styles-file}
The ODT export back-end uses the file pointed to by this variable,
such as @samp{styles.xml}, for the final output.  It can take one of the
following values:

@table @asis
@item @samp{FILE.xml}
Use this file instead of the default @samp{styles.xml}

@item @samp{FILE.odt} or @samp{FILE.ott}
Use the @samp{styles.xml} contained in the specified OpenDocument
Text or Template file

@item @samp{FILE.odt} or @samp{FILE.ott} and a subset of included files
Use the @samp{styles.xml} contained in the specified OpenDocument Text
or Template file.  Additionally extract the specified member files
and embed those within the final ODT document.

Use this option if the @samp{styles.xml} file references additional
files like header and footer images.

@item @code{nil}
Use the default @samp{styles.xml}.
@end table

@item @code{org-odt-content-template-file}
Use this variable to specify the blank @samp{content.xml} used in the
final output.
@end table

@anchor{Creating one-off styles}
@subsubheading Creating one-off styles

The ODT export back-end can read embedded raw OpenDocument XML from
the Org file.  Such direct formatting is useful for one-off instances.

@table @asis
@item Embedding ODT tags as part of regular text
Enclose OpenDocument syntax in @samp{@@@@odt:...@@@@} for inline markup.  For
example, to highlight a region of text do the following:

@example
@@@@odt:<text:span text:style-name="Highlight">This is highlighted
text</text:span>@@@@.  But this is regular text.
@end example

@strong{Hint:} To see the above example in action, edit the @samp{styles.xml}
(see @ref{x-orgodtstyles-xml, , Factory styles}) and add a custom @emph{Highlight} style as shown
below:

@example
<style:style style:name="Highlight" style:family="text">
  <style:text-properties fo:background-color="#ff0000"/>
</style:style>
@end example

@item Embedding a one-line OpenDocument XML
@cindex @samp{ODT}, keyword
The ODT export back-end can read one-liner options with @samp{#+ODT:} in
the Org file.  For example, to force a page break:

@example
#+ODT: <text:p text:style-name="PageBreak"/>
@end example

@strong{Hint:} To see the above example in action, edit your
@samp{styles.xml} (see @ref{x-orgodtstyles-xml, , Factory styles}) and add a custom @samp{PageBreak}
style as shown below.

@example
<style:style style:name="PageBreak" style:family="paragraph"
             style:parent-style-name="Text_20_body">
  <style:paragraph-properties fo:break-before="page"/>
</style:style>
@end example

@item Embedding a block of OpenDocument XML
The ODT export back-end can also read ODT export blocks for
OpenDocument XML@.  Such blocks use the @samp{#+BEGIN_EXPORT odt}
@dots{} @samp{#+END_EXPORT} constructs.

For example, to create a one-off paragraph that uses bold text, do
the following:

@example
#+BEGIN_EXPORT odt
  <text:p text:style-name="Text_20_body_20_bold">
  This paragraph is specially formatted and uses bold text.
  </text:p>
#+END_EXPORT
@end example
@end table

@anchor{Customizing tables in ODT export}
@subsubheading Customizing tables in ODT export

@cindex tables, in ODT export
@cindex @samp{ATTR_ODT}, keyword

Override the default table format by specifying a custom table style
with the @samp{#+ATTR_ODT} line.  For a discussion on default formatting of
tables, see @ref{Tables in ODT export}.

This feature closely mimics the way table templates are defined in the
OpenDocument-v1.2 specification@footnote{@uref{http://docs.oasis-open.org/office/v1.2/OpenDocument-v1.2.html, OpenDocument-v1.2 Specification}}.

@vindex org-odt-table-styles
For quick preview of this feature, install the settings below and export the
table that follows:

@lisp
(setq org-export-odt-table-styles
      (append org-export-odt-table-styles
              '(("TableWithHeaderRowAndColumn" "Custom"
                 ((use-first-row-styles . t)
                  (use-first-column-styles . t)))
                ("TableWithFirstRowandLastRow" "Custom"
                 ((use-first-row-styles . t)
                  (use-last-row-styles . t))))))
@end lisp

@example
#+ATTR_ODT: :style TableWithHeaderRowAndColumn
| Name  | Phone | Age |
| Peter |  1234 |  17 |
| Anna  |  4321 |  25 |
@end example

The example above used @samp{Custom} template and installed two table
styles @samp{TableWithHeaderRowAndColumn} and
@samp{TableWithFirstRowandLastRow}.  @strong{Important:} The OpenDocument styles
needed for producing the above template were pre-defined.  They are
available in the section marked @samp{Custom Table Template} in
@samp{OrgOdtContentTemplate.xml} (see @ref{x-orgodtcontenttemplate-xml, , Factory styles}).  For adding new
templates, define new styles there.

To use this feature proceed as follows:

@enumerate
@item
Create a table template@footnote{See the @samp{<table:table-template>} element of the
OpenDocument-v1.2 specification.}.

A table template is set of @samp{table-cell} and @samp{paragraph} styles for
each of the following table cell categories:

@itemize
@item
Body
@item
First column
@item
Last column
@item
First row
@item
Last row
@item
Even row
@item
Odd row
@item
Even column
@item
Odd Column
@end itemize

The names for the above styles must be chosen based on the name of
the table template using a well-defined convention.

The naming convention is better illustrated with an example.  For
a table template with the name @samp{Custom}, the needed style names are
listed in the following table.

@multitable {aaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@headitem Cell type
@tab Cell style
@tab Paragraph style
@item Body
@tab @samp{CustomTableCell}
@tab @samp{CustomTableParagraph}
@item First column
@tab @samp{CustomFirstColumnTableCell}
@tab @samp{CustomFirstColumnTableParagraph}
@item Last column
@tab @samp{CustomLastColumnTableCell}
@tab @samp{CustomLastColumnTableParagraph}
@item First row
@tab @samp{CustomFirstRowTableCell}
@tab @samp{CustomFirstRowTableParagraph}
@item Last row
@tab @samp{CustomLastRowTableCell}
@tab @samp{CustomLastRowTableParagraph}
@item Even row
@tab @samp{CustomEvenRowTableCell}
@tab @samp{CustomEvenRowTableParagraph}
@item Odd row
@tab @samp{CustomOddRowTableCell}
@tab @samp{CustomOddRowTableParagraph}
@item Even column
@tab @samp{CustomEvenColumnTableCell}
@tab @samp{CustomEvenColumnTableParagraph}
@item Odd column
@tab @samp{CustomOddColumnTableCell}
@tab @samp{CustomOddColumnTableParagraph}
@end multitable

To create a table template with the name @samp{Custom}, define the above
styles in the @samp{<office:automatic-styles>} @dots{}
@samp{</office:automatic-styles>} element of the content template file
(see @ref{x-orgodtcontenttemplate-xml, , Factory styles}).

@item
Define a table style@footnote{See the attributes @samp{table:template-name},
@samp{table:use-first-row-styles}, @samp{table:use-last-row-styles},
@samp{table:use-first-column-styles}, @samp{table:use-last-column-styles},
@samp{table:use-banding-rows-styles}, and @samp{table:use-banding-column-styles}
of the @samp{<table:table>} element in the OpenDocument-v1.2 specification.}.

@vindex org-odt-table-styles
To define a table style, create an entry for the style in the
variable @code{org-odt-table-styles} and specify the following:

@itemize
@item
the name of the table template created in step (1),
@item
the set of cell styles in that template that are to be activated.
@end itemize

For example, the entry below defines two different table styles
@samp{TableWithHeaderRowAndColumn} and @samp{TableWithFirstRowandLastRow}
based on the same template @samp{Custom}.  The styles achieve their
intended effect by selectively activating the individual cell
styles in that template.

@lisp
(setq org-export-odt-table-styles
      (append org-export-odt-table-styles
              '(("TableWithHeaderRowAndColumn" "Custom"
                 ((use-first-row-styles . t)
                  (use-first-column-styles . t)))
                ("TableWithFirstRowandLastRow" "Custom"
                 ((use-first-row-styles . t)
                  (use-last-row-styles . t))))))
@end lisp

@item
Associate a table with the table style.

To do this, specify the table style created in step (2) as part of
the @samp{ATTR_ODT} line as shown below.

@example
#+ATTR_ODT: :style TableWithHeaderRowAndColumn
| Name  | Phone | Age |
| Peter |  1234 |  17 |
| Anna  |  4321 |  25 |
@end example
@end enumerate

@anchor{Validating OpenDocument XML}
@subsubheading Validating OpenDocument XML

Sometimes ODT format files may not open due to @samp{.odt} file corruption.
To verify if such a file is corrupt, validate it against the
OpenDocument Relax NG Compact (RNC) syntax schema.  But first the
@samp{.odt} files have to be decompressed using @samp{zip}.  Note that @samp{.odt}
files are ZIP archives: @ref{File Archives,,,emacs,}.  The contents of
ODT files are in XML@.  For general help with validation---and
schema-sensitive editing---of XML files: @ref{Introduction,,,nxml-mode,}.

@vindex org-export-odt-schema-dir
Customize @code{org-odt-schema-dir} to point to a directory with
OpenDocument RNC files and the needed schema-locating rules.  The ODT
export back-end takes care of updating the
@code{rng-schema-locating-files}.

@node Org Export
@section Org Export

@cindex Org export
@emph{org} export back-end creates a normalized version of the Org document
in current buffer.  The exporter evaluates Babel code (see @ref{Evaluating Code Blocks}) and removes content specific to other back-ends.

@anchor{Org export commands}
@subheading Org export commands

@table @asis
@item @kbd{C-c C-e O o} (@code{org-org-export-to-org})
@kindex C-c C-e O o
@findex org-org-export-to-org
Export as an Org file with a @samp{.org} extension.  For @samp{myfile.org},
Org exports to @samp{myfile.org.org}, overwriting without warning.

@item @kbd{C-c C-e O v} (~~)
@kindex C-c C-e O v
Export to an Org file, then open it.
@end table

@node Texinfo Export
@section Texinfo Export

@menu
* Texinfo export commands::      Invoking commands.
* Texinfo specific export settings:: Setting the environment.
* Texinfo file header::          Generating the header.
* Texinfo title and copyright page:: Creating preamble pages.
* Info directory file::          Installing a manual in Info file hierarchy.
* Headings and sectioning structure:: Building document structure.
* Indices::                      Creating indices.
* Quoting Texinfo code::         Incorporating literal Texinfo code.
* Plain lists in Texinfo export:: List attributes.
* Tables in Texinfo export::     Table attributes.
* Images in Texinfo export::     Image attributes.
* Quotations in Texinfo export:: Quote block attributes.
* Special blocks in Texinfo export:: Special block attributes.
* A Texinfo example::            Processing Org to Texinfo.
@end menu

@node Texinfo export commands
@subsection Texinfo export commands

@table @asis
@item @kbd{C-c C-e i t} (@code{org-texinfo-export-to-texinfo})
@kindex C-c C-e i t
@findex org-texinfo-export-to-texinfo
Export as a Texinfo file with @samp{.texi} extension.  For @samp{myfile.org},
Org exports to @samp{myfile.texi}, overwriting without warning.

@item @kbd{C-c C-e i i} (@code{org-texinfo-export-to-info})
@kindex C-c C-e i i
@findex org-texinfo-export-to-info
@vindex org-texinfo-info-process
Export to Texinfo format first and then process it to make an Info
file.  To generate other formats, such as DocBook, customize the
@code{org-texinfo-info-process} variable.
@end table

@node Texinfo specific export settings
@subsection Texinfo specific export settings

The Texinfo export back-end has several additional keywords for
customizing Texinfo output.  Setting these keywords works similar to
the general options (see @ref{Export Settings}).

@table @asis
@item @samp{SUBTITLE}
@cindex @samp{SUBTITLE}, keyword
The document subtitle.

@item @samp{SUBAUTHOR}
@cindex @samp{SUBAUTHOR}, keyword
Additional authors for the document.

@item @samp{TEXINFO_FILENAME}
@cindex @samp{TEXINFO_FILENAME}, keyword
The Texinfo filename.

@item @samp{TEXINFO_CLASS}
@cindex @samp{TEXINFO_CLASS}, keyword
@vindex org-texinfo-default-class
The default document class (@code{org-texinfo-default-class}), which must
be a member of @code{org-texinfo-classes}.

@item @samp{TEXINFO_HEADER}
@cindex @samp{TEXINFO_HEADER}, keyword
Arbitrary lines inserted at the end of the header.

@item @samp{TEXINFO_POST_HEADER}
@cindex @samp{TEXINFO_POST_HEADER}, keyword
Arbitrary lines inserted after the end of the header.

@item @samp{TEXINFO_DIR_CATEGORY}
@cindex @samp{TEXINFO_DIR_CATEGORY}, keyword
The directory category of the document.

@item @samp{TEXINFO_DIR_TITLE}
@cindex @samp{TEXINFO_DIR_TITLE}, keyword
The directory title of the document.

@item @samp{TEXINFO_DIR_DESC}
@cindex @samp{TEXINFO_DIR_DESC}, keyword
The directory description of the document.

@item @samp{TEXINFO_PRINTED_TITLE}
@cindex @samp{TEXINFO_PRINTED_TITLE}, keyword
The printed title of the document.
@end table

@node Texinfo file header
@subsection Texinfo file header

@cindex @samp{TEXINFO_FILENAME}, keyword
After creating the header for a Texinfo file, the Texinfo back-end
automatically generates a name and destination path for the Info file.
To override this default with a more sensible path and name, specify
the @samp{TEXINFO_FILENAME} keyword.

@vindex org-texinfo-coding-system
@cindex @samp{TEXINFO_HEADER}, keyword
Along with the output's file name, the Texinfo header also contains
language details (see @ref{Export Settings}) and encoding system as set in
the @code{org-texinfo-coding-system} variable.  Insert @samp{TEXINFO_HEADER}
keywords for each additional command in the header, for example:

@example
#+TEXINFO_HEADER: @@synindex
@end example


@cindex @samp{TEXINFO_CLASS}, keyword
@vindex org-texinfo-classes
Instead of repeatedly installing the same set of commands, define
a class in @code{org-texinfo-classes} once, and then activate it in the
document by setting the @samp{TEXINFO_CLASS} keyword to that class.

@node Texinfo title and copyright page
@subsection Texinfo title and copyright page

@cindex @samp{TEXINFO_PRINTED_TITLE}, keyword
The default template for hard copy output has a title page with
@samp{TITLE} and @samp{AUTHOR} keywords (see @ref{Export Settings}).  To replace the
regular title with something different for the printed version, use
the @samp{TEXINFO_PRINTED_TITLE} and @samp{SUBTITLE} keywords.  Both expect raw
Texinfo code for setting their values.

@cindex @samp{SUBAUTHOR}, keyword
If one @samp{AUTHOR} line is not sufficient, add multiple @samp{SUBAUTHOR}
keywords.  They have to be set in raw Texinfo code.

@example
#+AUTHOR: Jane Smith
#+SUBAUTHOR: John Doe
#+TEXINFO_PRINTED_TITLE: This Long Title@@@@inlinefmt@{tex,@@*@} Is Broken in @@TeX@{@}
@end example

@cindex @samp{COPYING}, property
Copying material is defined in a dedicated headline with a non-@code{nil}
@samp{COPYING} property.  The back-end inserts the contents within
a @samp{@@copying} command at the beginning of the document.  The heading
itself does not appear in the structure of the document.

Copyright information is printed on the back of the title page.

@example
* Legalese
  :PROPERTIES:
  :COPYING: t
  :END:

  This is a short example of a complete Texinfo file, version 1.0.

  Copyright \copy 2016 Free Software Foundation, Inc.
@end example

@node Info directory file
@subsection Info directory file

@cindex @samp{dir} file, in Texinfo export
@cindex Info directory file, in Texinfo export
@cindex @code{install-info}, in Texinfo export

@cindex @samp{TEXINFO_DIR_CATEGORY}, keyword
@cindex @samp{TEXINFO_DIR_TITLE}, keyword
@cindex @samp{TEXINFO_DIR_DESC}, keyword
The end result of the Texinfo export process is the creation of an
Info file.  This Info file's metadata has variables for category,
title, and description: @samp{TEXINFO_DIR_CATEGORY}, @samp{TEXINFO_DIR_TITLE},
and @samp{TEXINFO_DIR_DESC} keywords that establish where in the Info
hierarchy the file fits.

Here is an example that writes to the Info directory file:

@example
#+TEXINFO_DIR_CATEGORY: Emacs
#+TEXINFO_DIR_TITLE: Org Mode: (org)
#+TEXINFO_DIR_DESC: Outline-based notes management and organizer
@end example

@node Headings and sectioning structure
@subsection Headings and sectioning structure

@vindex org-texinfo-classes
@vindex org-texinfo-default-class
@cindex @samp{TEXINFO_CLASS}, keyword
The Texinfo export back-end uses a pre-defined scheme to convert Org
headlines to equivalent Texinfo structuring commands.  A scheme like
this maps top-level headlines to numbered chapters tagged as
@code{@@chapter} and lower-level headlines to unnumbered chapters tagged as
@code{@@unnumbered}.  To override such mappings to introduce @code{@@part} or
other Texinfo structuring commands, define a new class in
@code{org-texinfo-classes}.  Activate the new class with the
@samp{TEXINFO_CLASS} keyword.  When no new class is defined and activated,
the Texinfo export back-end defaults to the
@code{org-texinfo-default-class}.

If an Org headline's level has no associated Texinfo structuring
command, or is below a certain threshold (see @ref{Export Settings}), then
the Texinfo export back-end makes it into a list item.

@cindex @samp{APPENDIX}, property
The Texinfo export back-end makes any headline with a non-@code{nil}
@samp{APPENDIX} property into an appendix.  This happens independent of the
Org headline level or the @samp{TEXINFO_CLASS} keyword.

@cindex @samp{ALT_TITLE}, property
@cindex @samp{DESCRIPTION}, property
The Texinfo export back-end creates a menu entry after the Org
headline for each regular sectioning structure.  To override this with
a shorter menu entry, use the @samp{ALT_TITLE} property (see @ref{Table of Contents}).  Texinfo menu entries also have an option for a longer
@samp{DESCRIPTION} property.  Here's an example that uses both to override
the default menu entry:

@example
* Controlling Screen Display
  :PROPERTIES:
  :ALT_TITLE: Display
  :DESCRIPTION: Controlling Screen Display
  :END:
@end example

@cindex Top node, in Texinfo export
The text before the first headline belongs to the @emph{Top} node, i.e.,
the node in which a reader enters an Info manual.  As such, it is
expected not to appear in printed output generated from the @samp{.texi}
file.  See @ref{The Top Node,,,texinfo,}, for more information.

@node Indices
@subsection Indices

@cindex @samp{CINDEX}, keyword
@cindex concept index, in Texinfo export
@cindex @samp{FINDEX}, keyword
@cindex function index, in Texinfo export
@cindex @samp{KINDEX}, keyword
@cindex keystroke index, in Texinfo export
@cindex @samp{PINDEX}, keyword
@cindex program index, in Texinfo export
@cindex @samp{TINDEX}, keyword
@cindex data type index, in Texinfo export
@cindex @samp{VINDEX}, keyword
@cindex variable index, in Texinfo export
The Texinfo export back-end recognizes these indexing keywords if used
in the Org file: @samp{CINDEX}, @samp{FINDEX}, @samp{KINDEX}, @samp{PINDEX}, @samp{TINDEX} and
@samp{VINDEX}.  Write their value as verbatim Texinfo code; in particular,
@samp{@{}, @samp{@}} and @samp{@@} characters need to be escaped with @samp{@@} if they do not
belong to a Texinfo command.

@example
#+CINDEX: Defining indexing entries
@end example


@cindex @samp{INDEX}, property
For the back-end to generate an index entry for a headline, set the
@samp{INDEX} property to @samp{cp} or @samp{vr}.  These abbreviations come from
Texinfo that stand for concept index and variable index.  The Texinfo
manual has abbreviations for all other kinds of indexes.  The back-end
exports the headline as an unnumbered chapter or section command, and
then inserts the index after its contents.

@example
* Concept Index
  :PROPERTIES:
  :INDEX: cp
  :END:
@end example

@node Quoting Texinfo code
@subsection Quoting Texinfo code

Use any of the following three methods to insert or escape raw Texinfo
code:

@cindex @samp{TEXINFO}, keyword
@cindex @samp{BEGIN_EXPORT texinfo}
@example
Richard @@@@texinfo:@@sc@{@@@@Stallman@@@@texinfo:@}@@@@ commence' GNU.

#+TEXINFO: @@need800
This paragraph is preceded by...

#+BEGIN_EXPORT texinfo
  @@auindex Johnson, Mark
  @@auindex Lakoff, George
#+END_EXPORT
@end example

@node Plain lists in Texinfo export
@subsection Plain lists in Texinfo export

@cindex @samp{ATTR_TEXINFO}, keyword
@cindex two-column tables, in Texinfo export
@cindex table-type, Texinfo attribute
The Texinfo export back-end by default converts description lists in
the Org file using the default command @samp{@@table}, which results in
a table with two columns.  To change this behavior, set @samp{:table-type}
attribute to either @samp{ftable} or @samp{vtable} value.  For more information,
see @ref{Two-column Tables,,,texinfo,}.

@vindex org-texinfo-table-default-markup
@cindex indic, Texinfo attribute
The Texinfo export back-end by default also applies a text highlight
based on the defaults stored in @code{org-texinfo-table-default-markup}.
To override the default highlight command, specify another one with
the @samp{:indic} attribute.

@cindex multiple items in Texinfo lists
@cindex sep, Texinfo attribute
Org syntax is limited to one entry per list item.  Nevertheless, the
Texinfo export back-end can split that entry according to any text
provided through the @samp{:sep} attribute.  Each part then becomes a new
entry in the first column of the table.

The following example illustrates all the attributes above:

@example
#+ATTR_TEXINFO: :table-type vtable :sep , :indic asis
- foo, bar :: This is the common text for variables foo and bar.
@end example

@noindent
becomes

@example
@@vtable @@asis
@@item foo
@@itemx bar
This is the common text for variables foo and bar.
@@end table
@end example

@cindex lettered lists, in Texinfo export
@cindex enum, Texinfo attribute
Ordered lists are numbered when exported to Texinfo format.  Such
numbering obeys any counter (see @ref{Plain Lists}) in the first item of
the list.  The @samp{:enum} attribute also let you start the list at
a specific number, or switch to a lettered list, as illustrated here

@example
#+ATTR_TEXINFO: :enum A
1. Alpha
2. Bravo
3. Charlie
@end example

@node Tables in Texinfo export
@subsection Tables in Texinfo export

@cindex @samp{ATTR_TEXINFO}, keyword
When exporting tables, the Texinfo export back-end uses the widest
cell width in each column.  To override this and instead specify as
fractions of line length, use the @samp{:columns} attribute.  See example
below.

@example
#+ATTR_TEXINFO: :columns .5 .5
| a cell | another cell |
@end example

@node Images in Texinfo export
@subsection Images in Texinfo export

@cindex @samp{ATTR_TEXINFO}, keyword
Insert a file link to the image in the Org file, and the Texinfo
export back-end inserts the image.  These links must have the usual
supported image extensions and no descriptions.  To scale the image,
use @samp{:width} and @samp{:height} attributes.  For alternate text, use @samp{:alt}
and specify the text using Texinfo code, as shown in the example:

@example
#+ATTR_TEXINFO: :width 1in :alt Alternate @@i@{text@}
[[ridt.pdf]]
@end example

@node Quotations in Texinfo export
@subsection Quotations in Texinfo export

@cindex @samp{ATTR_TEXINFO}, keyword
You can write the text of a quotation within a quote block (see
@ref{Paragraphs}).  You may also emphasize some text at the beginning of
the quotation with the @samp{:tag} attribute.

@example
#+ATTR_TEXINFO: :tag Warning
#+BEGIN_QUOTE
Striking your thumb with a hammer may cause severe pain and discomfort.
#+END_QUOTE
@end example

To specify the author of the quotation, use the @samp{:author} attribute.

@example
#+ATTR_TEXINFO: :author King Arthur
#+BEGIN_QUOTE
The Lady of the Lake, her arm clad in the purest shimmering samite,
held aloft Excalibur from the bosom of the water, signifying by divine
providence that I, Arthur, was to carry Excalibur. That is why I am
your king.
#+END_QUOTE
@end example

@node Special blocks in Texinfo export
@subsection Special blocks in Texinfo export

@cindex @samp{ATTR_TEXINFO}, keyword

The Texinfo export back-end converts special blocks to commands with
the same name.  It also adds any @samp{:options} attributes to the end of
the command, as shown in this example:

@example
#+ATTR_TEXINFO: :options org-org-export-to-org ...
#+BEGIN_defun
  A somewhat obsessive function name.
#+END_defun
@end example

@noindent
becomes

@example
@@defun org-org-export-to-org ...
  A somewhat obsessive function name.
@@end defun
@end example

@node A Texinfo example
@subsection A Texinfo example

Here is a more detailed example Org file.  See
@ref{GNU Sample Texts,,,texinfo,} for an equivalent example using
Texinfo code.

@example
#+TITLE: GNU Sample @{@{@{version@}@}@}
#+SUBTITLE: for version @{@{@{version@}@}@}, @{@{@{updated@}@}@}
#+AUTHOR: A.U. Thor
#+EMAIL: bug-sample@@gnu.org

#+OPTIONS: ':t toc:t author:t email:t
#+LANGUAGE: en

#+MACRO: version 2.0
#+MACRO: updated last updated 4 March 2014

#+TEXINFO_FILENAME: sample.info
#+TEXINFO_HEADER: @@syncodeindex pg cp

#+TEXINFO_DIR_CATEGORY: Texinfo documentation system
#+TEXINFO_DIR_TITLE: sample: (sample)
#+TEXINFO_DIR_DESC: Invoking sample

#+TEXINFO_PRINTED_TITLE: GNU Sample

This manual is for GNU Sample (version @{@{@{version@}@}@},
@{@{@{updated@}@}@}).

* Copying
  :PROPERTIES:
  :COPYING:  t
  :END:

  This manual is for GNU Sample (version @{@{@{version@}@}@},
  @{@{@{updated@}@}@}), which is an example in the Texinfo documentation.

  Copyright \copy 2016 Free Software Foundation, Inc.

  #+BEGIN_QUOTE
  Permission is granted to copy, distribute and/or modify this
  document under the terms of the GNU Free Documentation License,
  Version 1.3 or any later version published by the Free Software
  Foundation; with no Invariant Sections, with no Front-Cover Texts,
  and with no Back-Cover Texts.  A copy of the license is included in
  the section entitled "GNU Free Documentation License".
  #+END_QUOTE

* Invoking sample

  #+PINDEX: sample
  #+CINDEX: invoking @@command@{sample@}

  This is a sample manual.  There is no sample program to invoke, but
  if there were, you could see its basic usage and command line
  options here.

* GNU Free Documentation License
  :PROPERTIES:
  :APPENDIX: t
  :END:

  #+INCLUDE: fdl.org

* Index
  :PROPERTIES:
  :INDEX:    cp
  :END:
@end example

@node iCalendar Export
@section iCalendar Export

@cindex iCalendar export

A large part of Org mode's interoperability success is its ability to
easily export to or import from external applications.  The iCalendar
export back-end takes calendar data from Org files and exports to the
standard iCalendar format.

@vindex org-icalendar-include-todo
@vindex org-icalendar-use-deadline
@vindex org-icalendar-use-scheduled
The iCalendar export back-end can also incorporate TODO entries based
on the configuration of the @code{org-icalendar-include-todo} variable.
The back-end exports plain timestamps as @samp{VEVENT}, TODO items as
@samp{VTODO}, and also create events from deadlines that are in non-TODO
items.  The back-end uses the deadlines and scheduling dates in Org
TODO items for setting the start and due dates for the iCalendar TODO
entry.  Consult the @code{org-icalendar-use-deadline} and
@code{org-icalendar-use-scheduled} variables for more details.

@vindex org-icalendar-categories
@vindex org-icalendar-alarm-time
For tags on the headline, the iCalendar export back-end makes them
into iCalendar categories.  To tweak the inheritance of tags and TODO
states, configure the variable @code{org-icalendar-categories}.  To assign
clock alarms based on time, configure the @code{org-icalendar-alarm-time}
variable.

@vindex org-icalendar-store-UID
@cindex @samp{ID}, property
The iCalendar format standard requires globally unique identifier---or
UID---for each entry.  The iCalendar export back-end creates UIDs
during export.  To save a copy of the UID in the Org file set the
variable @code{org-icalendar-store-UID}.  The back-end looks for the @samp{ID}
property of the entry for re-using the same UID for subsequent
exports.

Since a single Org entry can result in multiple iCalendar
entries---timestamp, deadline, scheduled item, or TODO item---Org adds
prefixes to the UID, depending on which part of the Org entry
triggered the creation of the iCalendar entry.  Prefixing ensures UIDs
remains unique, yet enable synchronization programs trace the
connections.

@table @asis
@item @kbd{C-c C-e c f} (@code{org-icalendar-export-to-ics})
@kindex C-c C-e c f
@findex org-icalendar-export-to-ics
Create iCalendar entries from the current Org buffer and store them
in the same directory, using a file extension @samp{.ics}.

@item @kbd{C-c C-e c a} (@code{org-icalendar-export-agenda-files})
@kindex C-c C-e c a
@findex org-icalendar-export-agenda-files
Create iCalendar entries from Org files in @code{org-agenda-files} and
store in a separate iCalendar file for each Org file.

@item @kbd{C-c C-e c c} (@code{org-icalendar-combine-agenda-files})
@kindex C-c C-e c c
@findex org-icalendar-combine-agenda-files
@vindex org-icalendar-combined-agenda-file
Create a combined iCalendar file from Org files in
@code{org-agenda-files} and write it to
@code{org-icalendar-combined-agenda-file} file name.
@end table

@cindex @samp{SUMMARY}, property
@cindex @samp{DESCRIPTION}, property
@cindex @samp{LOCATION}, property
@cindex @samp{TIMEZONE}, property
@cindex @samp{CLASS}, property
The iCalendar export back-end includes @samp{SUMMARY}, @samp{DESCRIPTION},
@samp{LOCATION}, @samp{TIMEZONE} and @samp{CLASS} properties from the Org entries
when exporting.  To force the back-end to inherit the @samp{LOCATION},
@samp{TIMEZONE} and @samp{CLASS} properties, configure the
@code{org-use-property-inheritance} variable.

@vindex org-icalendar-include-body
When Org entries do not have @samp{SUMMARY}, @samp{DESCRIPTION}, @samp{LOCATION} and
@samp{CLASS} properties, the iCalendar export back-end derives the summary
from the headline, and derives the description from the body of the
Org item.  The @code{org-icalendar-include-body} variable limits the
maximum number of characters of the content are turned into its
description.

The @samp{TIMEZONE} property can be used to specify a per-entry time zone,
and is applied to any entry with timestamp information.  Time zones
should be specified as per the IANA time zone database format, e.g.,
@samp{Asia/Almaty}.  Alternately, the property value can be @samp{UTC}, to force
UTC time for this entry only.

The @samp{CLASS} property can be used to specify a per-entry visibility
class or access restrictions, and is applied to any entry with class
information.  The iCalendar standard defines three visibility classes:
@table @asis
@item @samp{PUBLIC}
The entry is publicly visible (this is the default).
@item @samp{CONFIDENTIAL}
Only a limited group of clients get access to the
event.
@item @samp{PRIVATE}
The entry can be retrieved only by its owner.
@end table
The server should treat unknown class properties the same as
@samp{PRIVATE}.

Exporting to iCalendar format depends in large part on the
capabilities of the destination application.  Some are more lenient
than others.  Consult the Org mode FAQ for advice on specific
applications.

@node Other Built-in Back-ends
@section Other Built-in Back-ends

Other export back-ends included with Org are:

@itemize
@item
@samp{ox-man.el}: Export to a man page.
@end itemize

To activate such back-ends, either customize @code{org-export-backends} or
load directly with @samp{(require 'ox-man)}.  On successful load, the
back-end adds new keys in the export dispatcher (see @ref{The Export Dispatcher}).

Follow the comment section of such files, for example, @samp{ox-man.el},
for usage and configuration details.

@node Advanced Export Configuration
@section Advanced Export Configuration



@anchor{Hooks}
@subheading Hooks

@vindex org-export-before-processing-hook
@vindex org-export-before-parsing-hook
The export process executes two hooks before the actual exporting
begins.  The first hook, @code{org-export-before-processing-hook}, runs
before any expansions of macros, Babel code, and include keywords in
the buffer.  The second hook, @code{org-export-before-parsing-hook}, runs
before the buffer is parsed.

Functions added to these hooks are called with a single argument: the
export back-end actually used, as a symbol.  You may use them for
heavy duty structural modifications of the document.  For example, you
can remove every headline in the buffer during export like this:

@lisp
(defun my-headline-removal (backend)
  "Remove all headlines in the current buffer.
BACKEND is the export back-end being used, as a symbol."
  (org-map-entries
   (lambda () (delete-region (point) (line-beginning-position 2)))))

(add-hook 'org-export-before-parsing-hook 'my-headline-removal)
@end lisp

@anchor{Filters}
@subheading Filters

@cindex Filters, exporting
Filters are lists of functions to be applied to certain parts for
a given back-end.  The output from the first function in the filter is
passed on to the next function in the filter.  The final output is the
output from the final function in the filter.

The Org export process has many filter sets applicable to different
types of objects, plain text, parse trees, export options, and final
output formats.  The filters are named after the element type or
object type: @code{org-export-filter-TYPE-functions}, where @var{TYPE}
is the type targeted by the filter.  Valid types are:

@multitable @columnfractions 0.33 0.33 0.33
@item body
@tab bold
@tab babel-call
@item center-block
@tab clock
@tab code
@item diary-sexp
@tab drawer
@tab dynamic-block
@item entity
@tab example-block
@tab export-block
@item export-snippet
@tab final-output
@tab fixed-width
@item footnote-definition
@tab footnote-reference
@tab headline
@item horizontal-rule
@tab inline-babel-call
@tab inline-src-block
@item inlinetask
@tab italic
@tab item
@item keyword
@tab latex-environment
@tab latex-fragment
@item line-break
@tab link
@tab node-property
@item options
@tab paragraph
@tab parse-tree
@item plain-list
@tab plain-text
@tab planning
@item property-drawer
@tab quote-block
@tab radio-target
@item section
@tab special-block
@tab src-block
@item statistics-cookie
@tab strike-through
@tab subscript
@item superscript
@tab table
@tab table-cell
@item table-row
@tab target
@tab timestamp
@item underline
@tab verbatim
@tab verse-block
@end multitable

Here is an example filter that replaces non-breaking spaces @code{ } in the
Org buffer with @samp{~} for the @LaTeX{} back-end.

@lisp
(defun my-latex-filter-nobreaks (text backend info)
  "Ensure \" \" are properly handled in LaTeX export."
  (when (org-export-derived-backend-p backend 'latex)
    (replace-regexp-in-string " " "~" text)))

(add-to-list 'org-export-filter-plain-text-functions
             'my-latex-filter-nobreaks)
@end lisp

A filter requires three arguments: the code to be transformed, the
name of the back-end, and some optional information about the export
process.  The third argument can be safely ignored.  Note the use of
@code{org-export-derived-backend-p} predicate that tests for @emph{latex}
back-end or any other back-end, such as @emph{beamer}, derived from
@emph{latex}.

@anchor{Defining filters for individual files}
@subheading Defining filters for individual files

The Org export can filter not just for back-ends, but also for
specific files through the @samp{BIND} keyword.  Here is an example with
two filters; one removes brackets from time stamps, and the other
removes strike-through text.  The filter functions are defined in
a code block in the same Org file, which is a handy location for
debugging.

@example
#+BIND: org-export-filter-timestamp-functions (tmp-f-timestamp)
#+BIND: org-export-filter-strike-through-functions (tmp-f-strike-through)
#+BEGIN_SRC emacs-lisp :exports results :results none
  (defun tmp-f-timestamp (s backend info)
    (replace-regexp-in-string "&[lg]t;\\|[][]" "" s))
  (defun tmp-f-strike-through (s backend info) "")
#+END_SRC
@end example

@anchor{Extending an existing back-end}
@subheading Extending an existing back-end

Some parts of the conversion process can be extended for certain
elements so as to introduce a new or revised translation.  That is how
the HTML export back-end was extended to handle Markdown format.  The
extensions work seamlessly so any aspect of filtering not done by the
extended back-end is handled by the original back-end.  Of all the
export customization in Org, extending is very powerful as it operates
at the parser level.

For this example, make the @emph{ascii} back-end display the language used
in a source code block.  Also make it display only when some attribute
is non-@code{nil}, like the following:

@example
#+ATTR_ASCII: :language t
@end example


Then extend ASCII back-end with a custom ``my-ascii'' back-end.

@lisp
(defun my-ascii-src-block (src-block contents info)
  "Transcode a SRC-BLOCK element from Org to ASCII.
CONTENTS is nil.  INFO is a plist used as a communication
channel."
  (if (not (org-export-read-attribute :attr_ascii src-block :language))
      (org-export-with-backend 'ascii src-block contents info)
    (concat
     (format ",--[ %s ]--\n%s`----"
             (org-element-property :language src-block)
             (replace-regexp-in-string
              "^" "| "
              (org-element-normalize-string
               (org-export-format-code-default src-block info)))))))

(org-export-define-derived-backend 'my-ascii 'ascii
  :translate-alist '((src-block . my-ascii-src-block)))
@end lisp

The @code{my-ascii-src-block} function looks at the attribute above the
current element.  If not true, hands over to @emph{ascii} back-end.  If
true, which it is in this example, it creates a box around the code
and leaves room for the inserting a string for language.  The last
form creates the new back-end that springs to action only when
translating @code{src-block} type elements.

To use the newly defined back-end, evaluate the following from an Org
buffer:

@lisp
(org-export-to-buffer 'my-ascii "*Org MY-ASCII Export*")
@end lisp

Further steps to consider would be an interactive function,
self-installing an item in the export dispatcher menu, and other
user-friendly improvements.

@node Export in Foreign Buffers
@section Export in Foreign Buffers

The export back-ends in Org often include commands to convert selected
regions.  A convenient feature of this in-place conversion is that the
exported output replaces the original source.  Here are such
functions:

@table @asis
@item @code{org-ascii-convert-region-to-ascii}
@findex org-ascii-convert-region-to-ascii
Convert the selected region into ASCII@.

@item @code{org-ascii-convert-region-to-utf8}
@findex org-ascii-convert-region-to-utf8
Convert the selected region into UTF-8.

@item @code{org-html-convert-region-to-html}
@findex org-html-convert-region-to-html
Convert the selected region into HTML@.

@item @code{org-latex-convert-region-to-latex}
@findex org-latex-convert-region-to-latex
Convert the selected region into @LaTeX{}.

@item @code{org-texinfo-convert-region-to-texinfo}
@findex org-texinfo-convert-region-to-texinfo
Convert the selected region into Texinfo.

@item @code{org-md-convert-region-to-md}
@findex org-md-convert-region-to-md
Convert the selected region into Markdown.
@end table

In-place conversions are particularly handy for quick conversion of
tables and lists in foreign buffers.  For example, in an HTML buffer,
write a list in Org syntax, select it, and convert it to HTML with
@kbd{M-x org-html-convert-region-to-html}.

@node Publishing
@chapter Publishing

@cindex publishing

Org includes a publishing management system that allows you to
configure automatic HTML conversion of @emph{projects} composed of
interlinked Org files.  You can also configure Org to automatically
upload your exported HTML pages and related attachments, such as
images and source code files, to a web server.

You can also use Org to convert files into PDF, or even combine HTML
and PDF conversion so that files are available in both formats on the
server.

Publishing has been contributed to Org by David O'Toole.

@menu
* Configuration::                Defining projects.
* Uploading Files::              How to get files up on the server.
* Sample Configuration::         Example projects.
* Triggering Publication::       Publication commands.
@end menu

@node Configuration
@section Configuration

Publishing needs significant configuration to specify files,
destination and many other properties of a project.

@menu
* Project alist::                The central configuration variable.
* Sources and destinations::     From here to there.
* Selecting files::              What files are part of the project?
* Publishing action::            Setting the function doing the publishing.
* Publishing options::           Tweaking HTML/@LaTeX{} export.
* Publishing links::             Which links keep working after publishing?
* Site map::                     Generating a list of all pages.
* Generating an index::          An index that reaches across pages.
@end menu

@node Project alist
@subsection The variable @code{org-publish-project-alist}

@cindex projects, for publishing

@vindex org-publish-project-alist
Publishing is configured almost entirely through setting the value of
one variable, called @code{org-publish-project-alist}.  Each element of the
list configures one project, and may be in one of the two following
forms:

@lisp
("project-name" :property value :property value ...)
@end lisp

@noindent
i.e., a well-formed property list with alternating keys and values,
or:

@lisp
("project-name" :components ("project-name" "project-name" ...))
@end lisp

In both cases, projects are configured by specifying property values.
A project defines the set of files that are to be published, as well
as the publishing configuration to use when publishing those files.
When a project takes the second form listed above, the individual
members of the @code{:components} property are taken to be sub-projects,
which group together files requiring different publishing options.
When you publish such a ``meta-project'', all the components are also
published, in the sequence given.

@node Sources and destinations
@subsection Sources and destinations for files

@cindex directories, for publishing

Most properties are optional, but some should always be set.  In
particular, Org needs to know where to look for source files, and
where to put published files.

@table @asis
@item @code{:base-directory}
Directory containing publishing source files.

@item @code{:publishing-directory}
Directory where output files are published.  You can directly
publish to a webserver using a file name syntax appropriate for the
Emacs tramp package.  Or you can publish to a local directory and
use external tools to upload your website (see @ref{Uploading Files}).

@item @code{:preparation-function}
Function or list of functions to be called before starting the
publishing process, for example, to run @samp{make} for updating files to
be published.  Each preparation function is called with a single
argument, the project property list.

@item @code{:completion-function}
Function or list of functions called after finishing the publishing
process, for example, to change permissions of the resulting files.
Each completion function is called with a single argument, the
project property list.
@end table

@node Selecting files
@subsection Selecting files

@cindex files, selecting for publishing

By default, all files with extension @samp{.org} in the base directory are
considered part of the project.  This can be modified by setting the
following properties

@table @asis
@item @code{:base-extension}
Extension---without the dot---of source files.  This actually is
a regular expression.  Set this to the symbol @code{any} if you want to
get all files in @code{:base-directory}, even without extension.

@item @code{:exclude}
Regular expression to match file names that should not be published,
even though they have been selected on the basis of their extension.

@item @code{:include}
List of files to be included regardless of @code{:base-extension} and
@code{:exclude}.

@item @code{:recursive}
Non-@code{nil} means, check base-directory recursively for files to
publish.
@end table

@node Publishing action
@subsection Publishing action

@cindex action, for publishing

Publishing means that a file is copied to the destination directory
and possibly transformed in the process.  The default transformation
is to export Org files as HTML files, and this is done by the function
@code{org-publish-org-to-html} which calls the HTML exporter (see @ref{HTML Export}).  But you can also publish your content as PDF files using
@code{org-publish-org-to-pdf}, or as ASCII, Texinfo, etc., using the
corresponding functions.

If you want to publish the Org file as an @samp{.org} file but with
@emph{archived}, @emph{commented}, and @emph{tag-excluded} trees removed, use
@code{org-publish-org-to-org}.  This produces @samp{file.org} and put it in the
publishing directory.  If you want a htmlized version of this file,
set the parameter @code{:htmlized-source} to @code{t}.  It produces
@samp{file.org.html} in the publishing directory@footnote{If the publishing directory is the same as the source
directory, @samp{file.org} is exported as @samp{file.org.org}, so you probably
do not want to do this.}.

Other files like images only need to be copied to the publishing
destination; for this you can use @code{org-publish-attachment}.  For
non-Org files, you always need to specify the publishing function:

@table @asis
@item @code{:publishing-function}
Function executing the publication of a file.  This may also be
a list of functions, which are all called in turn.

@item @code{:htmlized-source}
Non-@code{nil} means, publish htmlized source.
@end table

The function must accept three arguments: a property list containing
at least a @code{:publishing-directory} property, the name of the file to
be published, and the path to the publishing directory of the output
file.  It should take the specified file, make the necessary
transformation, if any, and place the result into the destination
folder.

@node Publishing options
@subsection Options for the exporters

@cindex options, for publishing
@cindex publishing options

The property list can be used to set many export options for the HTML
and @LaTeX{} exporters.  In most cases, these properties correspond to
user variables in Org.  The table below lists these properties along
with the variable they belong to.  See the documentation string for
the respective variable for details.

@vindex org-publish-project-alist
When a property is given a value in @code{org-publish-project-alist}, its
setting overrides the value of the corresponding user variable, if
any, during publishing.  Options set within a file (see @ref{Export Settings}), however, override everything.

@anchor{Generic properties}
@subsubheading Generic properties

@multitable {aaaaaaaaaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @code{:archived-trees}
@tab @code{org-export-with-archived-trees}
@item @code{:exclude-tags}
@tab @code{org-export-exclude-tags}
@item @code{:headline-levels}
@tab @code{org-export-headline-levels}
@item @code{:language}
@tab @code{org-export-default-language}
@item @code{:preserve-breaks}
@tab @code{org-export-preserve-breaks}
@item @code{:section-numbers}
@tab @code{org-export-with-section-numbers}
@item @code{:select-tags}
@tab @code{org-export-select-tags}
@item @code{:with-author}
@tab @code{org-export-with-author}
@item @code{:with-broken-links}
@tab @code{org-export-with-broken-links}
@item @code{:with-clocks}
@tab @code{org-export-with-clocks}
@item @code{:with-creator}
@tab @code{org-export-with-creator}
@item @code{:with-date}
@tab @code{org-export-with-date}
@item @code{:with-drawers}
@tab @code{org-export-with-drawers}
@item @code{:with-email}
@tab @code{org-export-with-email}
@item @code{:with-emphasize}
@tab @code{org-export-with-emphasize}
@item @code{:with-fixed-width}
@tab @code{org-export-with-fixed-width}
@item @code{:with-footnotes}
@tab @code{org-export-with-footnotes}
@item @code{:with-latex}
@tab @code{org-export-with-latex}
@item @code{:with-planning}
@tab @code{org-export-with-planning}
@item @code{:with-priority}
@tab @code{org-export-with-priority}
@item @code{:with-properties}
@tab @code{org-export-with-properties}
@item @code{:with-special-strings}
@tab @code{org-export-with-special-strings}
@item @code{:with-sub-superscript}
@tab @code{org-export-with-sub-superscripts}
@item @code{:with-tables}
@tab @code{org-export-with-tables}
@item @code{:with-tags}
@tab @code{org-export-with-tags}
@item @code{:with-tasks}
@tab @code{org-export-with-tasks}
@item @code{:with-timestamps}
@tab @code{org-export-with-timestamps}
@item @code{:with-title}
@tab @code{org-export-with-title}
@item @code{:with-toc}
@tab @code{org-export-with-toc}
@item @code{:with-todo-keywords}
@tab @code{org-export-with-todo-keywords}
@end multitable

@anchor{ASCII specific properties}
@subsubheading ASCII specific properties

@multitable {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @code{:ascii-bullets}
@tab @code{org-ascii-bullets}
@item @code{:ascii-caption-above}
@tab @code{org-ascii-caption-above}
@item @code{:ascii-charset}
@tab @code{org-ascii-charset}
@item @code{:ascii-global-margin}
@tab @code{org-ascii-global-margin}
@item @code{:ascii-format-drawer-function}
@tab @code{org-ascii-format-drawer-function}
@item @code{:ascii-format-inlinetask-function}
@tab @code{org-ascii-format-inlinetask-function}
@item @code{:ascii-headline-spacing}
@tab @code{org-ascii-headline-spacing}
@item @code{:ascii-indented-line-width}
@tab @code{org-ascii-indented-line-width}
@item @code{:ascii-inlinetask-width}
@tab @code{org-ascii-inlinetask-width}
@item @code{:ascii-inner-margin}
@tab @code{org-ascii-inner-margin}
@item @code{:ascii-links-to-notes}
@tab @code{org-ascii-links-to-notes}
@item @code{:ascii-list-margin}
@tab @code{org-ascii-list-margin}
@item @code{:ascii-paragraph-spacing}
@tab @code{org-ascii-paragraph-spacing}
@item @code{:ascii-quote-margin}
@tab @code{org-ascii-quote-margin}
@item @code{:ascii-table-keep-all-vertical-lines}
@tab @code{org-ascii-table-keep-all-vertical-lines}
@item @code{:ascii-table-use-ascii-art}
@tab @code{org-ascii-table-use-ascii-art}
@item @code{:ascii-table-widen-columns}
@tab @code{org-ascii-table-widen-columns}
@item @code{:ascii-text-width}
@tab @code{org-ascii-text-width}
@item @code{:ascii-underline}
@tab @code{org-ascii-underline}
@item @code{:ascii-verbatim-format}
@tab @code{org-ascii-verbatim-format}
@end multitable

@anchor{Beamer specific properties}
@subsubheading Beamer specific properties

@multitable {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @code{:beamer-theme}
@tab @code{org-beamer-theme}
@item @code{:beamer-column-view-format}
@tab @code{org-beamer-column-view-format}
@item @code{:beamer-environments-extra}
@tab @code{org-beamer-environments-extra}
@item @code{:beamer-frame-default-options}
@tab @code{org-beamer-frame-default-options}
@item @code{:beamer-outline-frame-options}
@tab @code{org-beamer-outline-frame-options}
@item @code{:beamer-outline-frame-title}
@tab @code{org-beamer-outline-frame-title}
@item @code{:beamer-subtitle-format}
@tab @code{org-beamer-subtitle-format}
@end multitable

@anchor{HTML specific properties}
@subsubheading HTML specific properties

@multitable {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @code{:html-allow-name-attribute-in-anchors}
@tab @code{org-html-allow-name-attribute-in-anchors}
@item @code{:html-checkbox-type}
@tab @code{org-html-checkbox-type}
@item @code{:html-container}
@tab @code{org-html-container-element}
@item @code{:html-divs}
@tab @code{org-html-divs}
@item @code{:html-doctype}
@tab @code{org-html-doctype}
@item @code{:html-extension}
@tab @code{org-html-extension}
@item @code{:html-footnote-format}
@tab @code{org-html-footnote-format}
@item @code{:html-footnote-separator}
@tab @code{org-html-footnote-separator}
@item @code{:html-footnotes-section}
@tab @code{org-html-footnotes-section}
@item @code{:html-format-drawer-function}
@tab @code{org-html-format-drawer-function}
@item @code{:html-format-headline-function}
@tab @code{org-html-format-headline-function}
@item @code{:html-format-inlinetask-function}
@tab @code{org-html-format-inlinetask-function}
@item @code{:html-head-extra}
@tab @code{org-html-head-extra}
@item @code{:html-head-include-default-style}
@tab @code{org-html-head-include-default-style}
@item @code{:html-head-include-scripts}
@tab @code{org-html-head-include-scripts}
@item @code{:html-head}
@tab @code{org-html-head}
@item @code{:html-home/up-format}
@tab @code{org-html-home/up-format}
@item @code{:html-html5-fancy}
@tab @code{org-html-html5-fancy}
@item @code{:html-indent}
@tab @code{org-html-indent}
@item @code{:html-infojs-options}
@tab @code{org-html-infojs-options}
@item @code{:html-infojs-template}
@tab @code{org-html-infojs-template}
@item @code{:html-inline-image-rules}
@tab @code{org-html-inline-image-rules}
@item @code{:html-inline-images}
@tab @code{org-html-inline-images}
@item @code{:html-link-home}
@tab @code{org-html-link-home}
@item @code{:html-link-org-files-as-html}
@tab @code{org-html-link-org-files-as-html}
@item @code{:html-link-up}
@tab @code{org-html-link-up}
@item @code{:html-link-use-abs-url}
@tab @code{org-html-link-use-abs-url}
@item @code{:html-mathjax-options}
@tab @code{org-html-mathjax-options}
@item @code{:html-mathjax-template}
@tab @code{org-html-mathjax-template}
@item @code{:html-metadata-timestamp-format}
@tab @code{org-html-metadata-timestamp-format}
@item @code{:html-postamble-format}
@tab @code{org-html-postamble-format}
@item @code{:html-postamble}
@tab @code{org-html-postamble}
@item @code{:html-preamble-format}
@tab @code{org-html-preamble-format}
@item @code{:html-preamble}
@tab @code{org-html-preamble}
@item @code{:html-self-link-headlines}
@tab @code{org-html-self-link-headlines}
@item @code{:html-table-align-individual-field}
@tab @code{de@{org-html-table-align-individual-fields}
@item @code{:html-table-attributes}
@tab @code{org-html-table-default-attributes}
@item @code{:html-table-caption-above}
@tab @code{org-html-table-caption-above}
@item @code{:html-table-data-tags}
@tab @code{org-html-table-data-tags}
@item @code{:html-table-header-tags}
@tab @code{org-html-table-header-tags}
@item @code{:html-table-row-tags}
@tab @code{org-html-table-row-tags}
@item @code{:html-table-use-header-tags-for-first-column}
@tab @code{org-html-table-use-header-tags-for-first-column}
@item @code{:html-tag-class-prefix}
@tab @code{org-html-tag-class-prefix}
@item @code{:html-text-markup-alist}
@tab @code{org-html-text-markup-alist}
@item @code{:html-todo-kwd-class-prefix}
@tab @code{org-html-todo-kwd-class-prefix}
@item @code{:html-toplevel-hlevel}
@tab @code{org-html-toplevel-hlevel}
@item @code{:html-use-infojs}
@tab @code{org-html-use-infojs}
@item @code{:html-validation-link}
@tab @code{org-html-validation-link}
@item @code{:html-viewport}
@tab @code{org-html-viewport}
@item @code{:html-wrap-src-lines}
@tab @code{org-html-wrap-src-lines}
@item @code{:html-xml-declaration}
@tab @code{org-html-xml-declaration}
@end multitable

@anchor{@LaTeX{} specific properties}
@subsubheading @LaTeX{} specific properties

@multitable {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @code{:latex-active-timestamp-format}
@tab @code{org-latex-active-timestamp-format}
@item @code{:latex-caption-above}
@tab @code{org-latex-caption-above}
@item @code{:latex-classes}
@tab @code{org-latex-classes}
@item @code{:latex-class}
@tab @code{org-latex-default-class}
@item @code{:latex-compiler}
@tab @code{org-latex-compiler}
@item @code{:latex-default-figure-position}
@tab @code{org-latex-default-figure-position}
@item @code{:latex-default-table-environment}
@tab @code{org-latex-default-table-environment}
@item @code{:latex-default-table-mode}
@tab @code{org-latex-default-table-mode}
@item @code{:latex-diary-timestamp-format}
@tab @code{org-latex-diary-timestamp-format}
@item @code{:latex-footnote-defined-format}
@tab @code{org-latex-footnote-defined-format}
@item @code{:latex-footnote-separator}
@tab @code{org-latex-footnote-separator}
@item @code{:latex-format-drawer-function}
@tab @code{org-latex-format-drawer-function}
@item @code{:latex-format-headline-function}
@tab @code{org-latex-format-headline-function}
@item @code{:latex-format-inlinetask-function}
@tab @code{org-latex-format-inlinetask-function}
@item @code{:latex-hyperref-template}
@tab @code{org-latex-hyperref-template}
@item @code{:latex-image-default-height}
@tab @code{org-latex-image-default-height}
@item @code{:latex-image-default-option}
@tab @code{org-latex-image-default-option}
@item @code{:latex-image-default-width}
@tab @code{org-latex-image-default-width}
@item @code{:latex-images-centered}
@tab @code{org-latex-images-centered}
@item @code{:latex-inactive-timestamp-format}
@tab @code{org-latex-inactive-timestamp-format}
@item @code{:latex-inline-image-rules}
@tab @code{org-latex-inline-image-rules}
@item @code{:latex-link-with-unknown-path-format}
@tab @code{org-latex-link-with-unknown-path-format}
@item @code{:latex-listings-langs}
@tab @code{org-latex-listings-langs}
@item @code{:latex-listings-options}
@tab @code{org-latex-listings-options}
@item @code{:latex-listings}
@tab @code{org-latex-listings}
@item @code{:latex-minted-langs}
@tab @code{org-latex-minted-langs}
@item @code{:latex-minted-options}
@tab @code{org-latex-minted-options}
@item @code{:latex-prefer-user-labels}
@tab @code{org-latex-prefer-user-labels}
@item @code{:latex-subtitle-format}
@tab @code{org-latex-subtitle-format}
@item @code{:latex-subtitle-separate}
@tab @code{org-latex-subtitle-separate}
@item @code{:latex-table-scientific-notation}
@tab @code{org-latex-table-scientific-notation}
@item @code{:latex-tables-booktabs}
@tab @code{org-latex-tables-booktabs}
@item @code{:latex-tables-centered}
@tab @code{org-latex-tables-centered}
@item @code{:latex-text-markup-alist}
@tab @code{org-latex-text-markup-alist}
@item @code{:latex-title-command}
@tab @code{org-latex-title-command}
@item @code{:latex-toc-command}
@tab @code{org-latex-toc-command}
@end multitable

@anchor{Markdown specific properties}
@subsubheading Markdown specific properties

@multitable {aaaaaaaaaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @code{:md-footnote-format}
@tab @code{org-md-footnote-format}
@item @code{:md-footnotes-section}
@tab @code{org-md-footnotes-section}
@item @code{:md-headline-style}
@tab @code{org-md-headline-style}
@end multitable

@anchor{ODT specific properties}
@subsubheading ODT specific properties

@multitable {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @code{:odt-content-template-file}
@tab @code{org-odt-content-template-file}
@item @code{:odt-display-outline-level}
@tab @code{org-odt-display-outline-level}
@item @code{:odt-fontify-srcblocks}
@tab @code{org-odt-fontify-srcblocks}
@item @code{:odt-format-drawer-function}
@tab @code{org-odt-format-drawer-function}
@item @code{:odt-format-headline-function}
@tab @code{org-odt-format-headline-function}
@item @code{:odt-format-inlinetask-function}
@tab @code{org-odt-format-inlinetask-function}
@item @code{:odt-inline-formula-rules}
@tab @code{org-odt-inline-formula-rules}
@item @code{:odt-inline-image-rules}
@tab @code{org-odt-inline-image-rules}
@item @code{:odt-pixels-per-inch}
@tab @code{org-odt-pixels-per-inch}
@item @code{:odt-styles-file}
@tab @code{org-odt-styles-file}
@item @code{:odt-table-styles}
@tab @code{org-odt-table-styles}
@item @code{:odt-use-date-fields}
@tab @code{org-odt-use-date-fields}
@end multitable

@anchor{Texinfo specific properties}
@subsubheading Texinfo specific properties

@multitable {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @code{:texinfo-active-timestamp-format}
@tab @code{org-texinfo-active-timestamp-format}
@item @code{:texinfo-classes}
@tab @code{org-texinfo-classes}
@item @code{:texinfo-class}
@tab @code{org-texinfo-default-class}
@item @code{:texinfo-table-default-markup}
@tab @code{org-texinfo-table-default-markup}
@item @code{:texinfo-diary-timestamp-format}
@tab @code{org-texinfo-diary-timestamp-format}
@item @code{:texinfo-filename}
@tab @code{org-texinfo-filename}
@item @code{:texinfo-format-drawer-function}
@tab @code{org-texinfo-format-drawer-function}
@item @code{:texinfo-format-headline-function}
@tab @code{org-texinfo-format-headline-function}
@item @code{:texinfo-format-inlinetask-function}
@tab @code{org-texinfo-format-inlinetask-function}
@item @code{:texinfo-inactive-timestamp-format}
@tab @code{org-texinfo-inactive-timestamp-format}
@item @code{:texinfo-link-with-unknown-path-format}
@tab @code{org-texinfo-link-with-unknown-path-format}
@item @code{:texinfo-node-description-column}
@tab @code{org-texinfo-node-description-column}
@item @code{:texinfo-table-scientific-notation}
@tab @code{org-texinfo-table-scientific-notation}
@item @code{:texinfo-tables-verbatim}
@tab @code{org-texinfo-tables-verbatim}
@item @code{:texinfo-text-markup-alist}
@tab @code{org-texinfo-text-markup-alist}
@end multitable

@node Publishing links
@subsection Publishing links

@cindex links, publishing

To create a link from one Org file to another, you would use something
like @samp{[[file:foo.org][The foo]]} or simply @samp{[[file:foo.org]]} (see @ref{External Links}).  When
published, this link becomes a link to @samp{foo.html}.  You can thus
interlink the pages of your ``Org web'' project and the links will work
as expected when you publish them to HTML@.  If you also publish the
Org source file and want to link to it, use an @samp{http} link instead of
a @samp{file:} link, because @samp{file} links are converted to link to the
corresponding @samp{.html} file.

You may also link to related files, such as images.  Provided you are
careful with relative file names, and provided you have also
configured Org to upload the related files, these links will work too.
See @ref{Complex example}, for an example of this
usage.

Eventually, links between published documents can contain some search
options (see @ref{Search Options}), which will be resolved to
the appropriate location in the linked file.  For example, once
published to HTML, the following links all point to a dedicated anchor
in @samp{foo.html}.

@example
[[file:foo.org::*heading]]
[[file:foo.org::#custom-id]]
[[file:foo.org::target]]
@end example

@node Site map
@subsection Generating a sitemap

@cindex sitemap, of published pages

The following properties may be used to control publishing of
a map of files for a given project.

@table @asis
@item @code{:auto-sitemap}
When non-@code{nil}, publish a sitemap during
@code{org-publish-current-project} or @code{org-publish-all}.

@item @code{:sitemap-filename}
Filename for output of sitemap.  Defaults to @samp{sitemap.org}, which
becomes @samp{sitemap.html}.

@item @code{:sitemap-title}
Title of sitemap page.  Defaults to name of file.

@item @code{:sitemap-format-entry}
@findex org-publish-find-date
@findex org-publish-find-property
@findex org-publish-find-title
With this option one can tell how a site-map entry is formatted in
the site-map.  It is a function called with three arguments: the
file or directory name relative to base directory of the project,
the site-map style and the current project.  It is expected to
return a string.  Default value turns file names into links and use
document titles as descriptions.  For specific formatting needs, one
can use @code{org-publish-find-date}, @code{org-publish-find-title} and
@code{org-publish-find-property}, to retrieve additional information
about published documents.

@item @code{:sitemap-function}
Plug-in function to use for generation of the sitemap.  It is called
with two arguments: the title of the site-map and a representation
of the files and directories involved in the project as a nested
list, which can further be transformed using @code{org-list-to-generic},
@code{org-list-to-subtree} and alike.  Default value generates a plain
list of links to all files in the project.

@item @code{:sitemap-sort-folders}
Where folders should appear in the sitemap.  Set this to @code{first}
(default) or @code{last} to display folders first or last, respectively.
When set to @code{ignore}, folders are ignored altogether.  Any other
value mixes files and folders.  This variable has no effect when
site-map style is @code{tree}.

@item @code{:sitemap-sort-files}
How the files are sorted in the site map.  Set this to
@code{alphabetically} (default), @code{chronologically} or
@code{anti-chronologically}.  @code{chronologically} sorts the files with
older date first while @code{anti-chronologically} sorts the files with
newer date first.  @code{alphabetically} sorts the files alphabetically.
The date of a file is retrieved with @code{org-publish-find-date}.

@item @code{:sitemap-ignore-case}
Should sorting be case-sensitive?  Default @code{nil}.

@item @code{:sitemap-file-entry-format}
With this option one can tell how a sitemap's entry is formatted in
the sitemap.  This is a format string with some escape sequences:
@code{%t} stands for the title of the file, @code{%a} stands for the author of
the file and @code{%d} stands for the date of the file.  The date is
retrieved with the @code{org-publish-find-date} function and formatted
with @code{org-publish-sitemap-date-format}.  Default @code{%t}.

@item @code{:sitemap-date-format}
Format string for the @code{format-time-string} function that tells how
a sitemap entry's date is to be formatted.  This property bypasses
@code{org-publish-sitemap-date-format} which defaults to @code{%Y-%m-%d}.
@end table

@node Generating an index
@subsection Generating an index

@cindex index, in a publishing project

Org mode can generate an index across the files of a publishing project.

@table @asis
@item @code{:makeindex}
When non-@code{nil}, generate in index in the file @samp{theindex.org} and
publish it as @samp{theindex.html}.
@end table

The file is created when first publishing a project with the
@code{:makeindex} set.  The file only contains a statement @samp{#+INCLUDE:
"theindex.inc"}.  You can then build around this include statement by
adding a title, style information, etc.

@cindex @samp{INDEX}, keyword
Index entries are specified with @samp{INDEX} keyword.  An entry that
contains an exclamation mark creates a sub item.

@example
*** Curriculum Vitae
#+INDEX: CV
#+INDEX: Application!CV
@end example

@node Uploading Files
@section Uploading Files

@cindex rsync
@cindex unison

For those people already utilizing third party sync tools such as
Rsync or Unison, it might be preferable not to use the built-in remote
publishing facilities of Org mode which rely heavily on Tramp.  Tramp,
while very useful and powerful, tends not to be so efficient for
multiple file transfer and has been known to cause problems under
heavy usage.

Specialized synchronization utilities offer several advantages.  In
addition to timestamp comparison, they also do content and
permissions/attribute checks.  For this reason you might prefer to
publish your web to a local directory---possibly even @emph{in place} with
your Org files---and then use Unison or Rsync to do the
synchronization with the remote host.

Since Unison, for example, can be configured as to which files to
transfer to a certain remote destination, it can greatly simplify the
project publishing definition.  Simply keep all files in the correct
location, process your Org files with @code{org-publish} and let the
synchronization tool do the rest.  You do not need, in this scenario,
to include attachments such as JPG, CSS or PNG files in the project
definition since the third-party tool syncs them.

Publishing to a local directory is also much faster than to a remote
one, so that you can afford more easily to republish entire projects.
If you set @code{org-publish-use-timestamps-flag} to @code{nil}, you gain the
main benefit of re-including any changed external files such as source
example files you might include with @samp{INCLUDE} keyword.  The timestamp
mechanism in Org is not smart enough to detect if included files have
been modified.

@node Sample Configuration
@section Sample Configuration

Below we provide two example configurations.  The first one is
a simple project publishing only a set of Org files.  The second
example is more complex, with a multi-component project.

@menu
* Simple example::               One-component publishing.
* Complex example::              A multi-component publishing example.
@end menu

@node Simple example
@subsection Example: simple publishing configuration

This example publishes a set of Org files to the @samp{public_html}
directory on the local machine.

@lisp
(setq org-publish-project-alist
      '(("org"
         :base-directory "~/org/"
         :publishing-directory "~/public_html"
         :section-numbers nil
         :table-of-contents nil
         :style "<link rel=\"stylesheet\"
                href=\"../other/mystyle.css\"
                type=\"text/css\"/>")))
@end lisp

@node Complex example
@subsection Example: complex publishing configuration

This more complicated example publishes an entire website, including
Org files converted to HTML, image files, Emacs Lisp source code, and
style sheets.  The publishing directory is remote and private files
are excluded.

To ensure that links are preserved, care should be taken to replicate
your directory structure on the web server, and to use relative file
paths.  For example, if your Org files are kept in @samp{~/org/} and your
publishable images in @samp{~/images/}, you would link to an image with

@example
file:../images/myimage.png
@end example


On the web server, the relative path to the image should be the same.
You can accomplish this by setting up an @samp{images/} folder in the right
place on the web server, and publishing images to it.

@lisp
(setq org-publish-project-alist
      '(("orgfiles"
         :base-directory "~/org/"
         :base-extension "org"
         :publishing-directory "/ssh:user@@host:~/html/notebook/"
         :publishing-function org-html-publish-to-html
         :exclude "PrivatePage.org" ;; regexp
         :headline-levels 3
         :section-numbers nil
         :with-toc nil
         :html-head "<link rel=\"stylesheet\"
                  href=\"../other/mystyle.css\" type=\"text/css\"/>"
         :html-preamble t)

        ("images"
         :base-directory "~/images/"
         :base-extension "jpg\\|gif\\|png"
         :publishing-directory "/ssh:user@@host:~/html/images/"
         :publishing-function org-publish-attachment)

        ("other"
         :base-directory "~/other/"
         :base-extension "css\\|el"
         :publishing-directory "/ssh:user@@host:~/html/other/"
         :publishing-function org-publish-attachment)
        ("website" :components ("orgfiles" "images" "other"))))
@end lisp

@node Triggering Publication
@section Triggering Publication

Once properly configured, Org can publish with the following commands:

@table @asis
@item @kbd{C-c C-e P x} (@code{org-publish})
@kindex C-c C-e P x
@findex org-publish
Prompt for a specific project and publish all files that belong to
it.

@item @kbd{C-c C-e P p} (@code{org-publish-current-project})
@kindex C-c C-e P p
@findex org-publish-current-project
Publish the project containing the current file.

@item @kbd{C-c C-e P f} (@code{org-publish-current-file})
@kindex C-c C-e P f
@findex org-publish-current-file
Publish only the current file.

@item @kbd{C-c C-e P a} (@code{org-publish-all})
@kindex C-c C-e P a
@findex org-publish-all
Publish every project.
@end table

@vindex org-publish-use-timestamps-flag
Org uses timestamps to track when a file has changed.  The above
functions normally only publish changed files.  You can override this
and force publishing of all files by giving a prefix argument to any
of the commands above, or by customizing the variable
@code{org-publish-use-timestamps-flag}.  This may be necessary in
particular if files include other files via @samp{SETUPFILE} or @samp{INCLUDE}
keywords.

@node Working with Source Code
@chapter Working with Source Code

@cindex source code, working with

Source code here refers to any plain text collection of computer
instructions, possibly with comments, written using a human-readable
programming language.  Org can manage source code in an Org document
when the source code is identified with begin and end markers.
Working with source code begins with identifying source code blocks.
A source code block can be placed almost anywhere in an Org document;
it is not restricted to the preamble or the end of the document.
However, Org cannot manage a source code block if it is placed inside
an Org comment or within a fixed width section.

Here is an example source code block in the Emacs Lisp language:

@example
#+BEGIN_SRC emacs-lisp
  (defun org-xor (a b)
     "Exclusive or."
     (if a (not b) b))
#+END_SRC
@end example

Org can manage the source code in the block delimited by @samp{#+BEGIN_SRC}
@dots{} @samp{#+END_SRC} in several ways that can simplify housekeeping tasks
essential to modern source code maintenance.  Org can edit, format,
extract, export, and publish source code blocks.  Org can also compile
and execute a source code block, then capture the results.  The Org
mode literature sometimes refers to source code blocks as @emph{live code}
blocks because they can alter the content of the Org document or the
material that it exports.  Users can control how live they want each
source code block by tweaking the header arguments (see @ref{Using Header Arguments}) for compiling, execution, extraction, and
exporting.

Source code blocks are one of many Org block types, which also include
``center'', ``comment'', ``dynamic'', ``example'', ``export'', ``quote'',
``special'', and ``verse''.  This section pertains to blocks between
@samp{#+BEGIN_SRC} and @samp{#+END_SRC}.

For editing and formatting a source code block, Org uses an
appropriate Emacs major mode that includes features specifically
designed for source code in that language.

Org can extract one or more source code blocks and write them to one
or more source files---a process known as @emph{tangling} in literate
programming terminology.

For exporting and publishing, Org's back-ends can format a source code
block appropriately, often with native syntax highlighting.

For executing and compiling a source code block, the user can
configure Org to select the appropriate compiler.  Org provides
facilities to collect the result of the execution or compiler output,
insert it into the Org document, and/or export it.  In addition to
text results, Org can insert links to other data types, including
audio, video, and graphics.  Org can also link a compiler error
message to the appropriate line in the source code block.

An important feature of Org's management of source code blocks is the
ability to pass variables, functions, and results to one another using
a common syntax for source code blocks in any language.  Although most
literate programming facilities are restricted to one language or
another, Org's language-agnostic approach lets the literate programmer
match each programming task with the appropriate computer language and
to mix them all together in a single Org document.  This
interoperability among languages explains why Org's source code
management facility was named @emph{Org Babel} by its originators, Eric
Schulte and Dan Davison.

Org mode fulfills the promise of easy verification and maintenance of
publishing reproducible research by keeping text, data, code,
configuration settings of the execution environment, the results of
the execution, and associated narratives, claims, references, and
internal and external links in a single Org document.

Details of Org's facilities for working with source code are described
in the following sections.

@menu
* Structure of Code Blocks::     Code block syntax described.
* Using Header Arguments::       Different ways to set header arguments.
* Environment of a Code Block::  Arguments, sessions, working directory...
* Evaluating Code Blocks::       Place results of evaluation in the Org buffer.
* Results of Evaluation::        Choosing a results type, post-processing...
* Exporting Code Blocks::        Export contents and/or results.
* Extracting Source Code::       Create pure source code files.
* Languages::                    List of supported code block languages.
* Editing Source Code::          Language major-mode editing.
* Noweb Reference Syntax::       Literate programming in Org mode.
* Library of Babel::             Use and contribute to a library of useful code blocks.
* Key bindings and Useful Functions:: Work quickly with code blocks.
* Batch Execution::              Call functions from the command line.
@end menu

@node Structure of Code Blocks
@section Structure of Code Blocks

@cindex code block, structure
@cindex source code, block structure
@cindex @samp{NAME} keyword, in source blocks
@cindex @samp{BEGIN_SRC}

Org offers two ways to structure source code in Org documents: in
a source code block, and directly inline.  Both specifications are
shown below.

A source code block conforms to this structure:

@example
#+NAME: <name>
#+BEGIN_SRC <language> <switches> <header arguments>
  <body>
#+END_SRC
@end example

Do not be put-off by having to remember the source block syntax.  Org
mode offers a command for wrapping existing text in a block (see
@ref{Structure Templates}).  Org also works with other completion systems
in Emacs, some of which predate Org and have custom domain-specific
languages for defining templates.  Regular use of templates reduces
errors, increases accuracy, and maintains consistency.

@cindex source code, inline
An inline code block conforms to this structure:

@example
src_<language>@{<body>@}
@end example


@noindent
or

@example
src_<language>[<header arguments>]@{<body>@}
@end example


@table @asis
@item @samp{#+NAME: <name>}
Optional.  Names the source block so it can be called, like
a function, from other source blocks or inline code to evaluate or
to capture the results.  Code from other blocks, other files, and
from table formulas (see @ref{The Spreadsheet}) can use the name to
reference a source block.  This naming serves the same purpose as
naming Org tables.  Org mode requires unique names.  For duplicate
names, Org mode's behavior is undefined.

@item @samp{#+BEGIN_SRC} @dots{} @samp{#+END_SRC}
Mandatory.  They mark the start and end of a block that Org
requires.  The @samp{#+BEGIN_SRC} line takes additional arguments, as
described next.

@item @samp{<language>}
@cindex language, in code blocks
Mandatory.  It is the identifier of the source code language in the
block.  See @ref{Languages}, for identifiers of supported languages.

@item @samp{<switches>}
@cindex switches, in code blocks
Optional.  Switches provide finer control of the code execution,
export, and format (see the discussion of switches in @ref{Literal Examples}).

@item @samp{<header arguments>}
@cindex header arguments, in code blocks
Optional.  Heading arguments control many aspects of evaluation,
export and tangling of code blocks (see @ref{Using Header Arguments}).
Using Org's properties feature, header arguments can be selectively
applied to the entire buffer or specific sub-trees of the Org
document.

@item @samp{<body>}
Source code in the dialect of the specified language identifier.
@end table

@node Using Header Arguments
@section Using Header Arguments

Org comes with many header arguments common to all languages.  New
header arguments are added for specific languages as they become
available for use in source code blocks.  A header argument is
specified with an initial colon followed by the argument's name in
lowercase.

Since header arguments can be set in several ways, Org prioritizes
them in case of overlaps or conflicts by giving local settings
a higher priority.  Header values in function calls, for example,
override header values from global defaults.

@anchor{System-wide header arguments}
@subheading System-wide header arguments

@vindex org-babel-default-header-args

@vindex org-babel-default-header-args
System-wide values of header arguments can be specified by customizing
the @code{org-babel-default-header-args} variable, which defaults to the
following values:

@example
:session    => "none"
:results    => "replace"
:exports    => "code"
:cache      => "no"
:noweb      => "no"
@end example

The example below sets @samp{:noweb} header arguments to @samp{yes}, which makes
Org expand @samp{:noweb} references by default.

@lisp
(setq org-babel-default-header-args
      (cons '(:noweb . "yes")
            (assq-delete-all :noweb org-babel-default-header-args)))
@end lisp

@cindex language specific default header arguments
@cindex default header arguments per language
Each language can have separate default header arguments by
customizing the variable @code{org-babel-default-header-args:<LANG>}, where
@var{<LANG>} is the name of the language.  For details, see the
language-specific online documentation at
@uref{https://orgmode.org/worg/org-contrib/babel/}.

@anchor{Header arguments in Org mode properties}
@subheading Header arguments in Org mode properties

For header arguments applicable to the buffer, use @samp{PROPERTY} keyword
anywhere in the Org file (see @ref{Property Syntax}).

The following example makes all the R code blocks execute in the same
session.  Setting @samp{:results} to @samp{silent} ignores the results of
executions for all blocks, not just R code blocks; no results inserted
for any block.

@example
#+PROPERTY: header-args:R  :session *R*
#+PROPERTY: header-args    :results silent
@end example

@vindex org-use-property-inheritance
Header arguments set through Org's property drawers (see @ref{Property Syntax}) apply at the sub-tree level on down.  Since these property
drawers can appear anywhere in the file hierarchy, Org uses outermost
call or source block to resolve the values.  Org ignores
@code{org-use-property-inheritance} setting.

In this example, @samp{:cache} defaults to @samp{yes} for all code blocks in the
sub-tree.

@example
* sample header
  :PROPERTIES:
  :header-args:    :cache yes
  :END:
@end example

@kindex C-c C-x p
@findex org-set-property
Properties defined through @code{org-set-property} function, bound to
@kbd{C-c C-x p}, apply to all active languages.  They override
properties set in @code{org-babel-default-header-args}.

@cindex language specific header arguments properties
@cindex header arguments per language
Language-specific header arguments are also read from properties
@samp{header-args:<LANG>} where @var{<LANG>} is the language
identifier.  For example,

@example
* Heading
  :PROPERTIES:
  :header-args:clojure:    :session *clojure-1*
  :header-args:R:          :session *R*
  :END:
** Subheading
  :PROPERTIES:
  :header-args:clojure:    :session *clojure-2*
  :END:
@end example

@noindent
would force separate sessions for Clojure blocks in @samp{Heading} and
@samp{Subheading}, but use the same session for all R blocks.  Blocks in
@samp{Subheading} inherit settings from @samp{Heading}.

@anchor{Code block specific header arguments}
@subheading Code block specific header arguments

Header arguments are most commonly set at the source code block level,
on the @samp{#+BEGIN_SRC} line.  Arguments set at this level take
precedence over those set in the @code{org-babel-default-header-args}
variable, and also those set as header properties.

In the following example, setting @samp{:results} to @samp{silent} makes it
ignore results of the code execution.  Setting @samp{:exports} to @samp{code}
exports only the body of the code block to HTML or @LaTeX{}.

@example
#+NAME: factorial
#+BEGIN_SRC haskell :results silent :exports code :var n=0
  fac 0 = 1
  fac n = n * fac (n-1)
#+END_SRC
@end example

The same header arguments in an inline code block:

@example
src_haskell[:exports both]@{fac 5@}
@end example


@cindex @samp{HEADER}, keyword
Code block header arguments can span multiple lines using @samp{#+HEADER:}
on each line.  Note that Org currently accepts the plural spelling of
@samp{#+HEADER:} only as a convenience for backward-compatibility.  It may
be removed at some point.

Multi-line header arguments on an unnamed code block:

@example
#+HEADER: :var data1=1
#+BEGIN_SRC emacs-lisp :var data2=2
   (message "data1:%S, data2:%S" data1 data2)
#+END_SRC

#+RESULTS:
: data1:1, data2:2
@end example

Multi-line header arguments on a named code block:

@example
#+NAME: named-block
#+HEADER: :var data=2
#+BEGIN_SRC emacs-lisp
  (message "data:%S" data)
#+END_SRC

#+RESULTS: named-block
  : data:2
@end example

@anchor{Header arguments in function calls}
@subheading Header arguments in function calls

Header arguments in function calls are the most specific and override
all other settings in case of an overlap.  They get the highest
priority.  Two @samp{#+CALL:} examples are shown below.  For the complete
syntax of @samp{CALL} keyword, see @ref{Evaluating Code Blocks}.

In this example, @samp{:exports results} header argument is applied to the
evaluation of the @samp{#+CALL:} line.

@example
#+CALL: factorial(n=5) :exports results
@end example


In this example, @samp{:session special} header argument is applied to the
evaluation of @samp{factorial} code block.

@example
#+CALL: factorial[:session special](n=5)
@end example

@node Environment of a Code Block
@section Environment of a Code Block



@anchor{Passing arguments}
@subheading Passing arguments

@cindex passing arguments to code blocks
@cindex arguments, in code blocks
@cindex @samp{var}, header argument
Use @samp{var} for passing arguments to source code blocks.  The specifics
of variables in code blocks vary by the source language and are
covered in the language-specific documentation.  The syntax for @samp{var},
however, is the same for all languages.  This includes declaring
a variable, and assigning a default value.

The following syntax is used to pass arguments to code blocks using
the @samp{var} header argument.

@example
:var NAME=ASSIGN
@end example


@noindent
@var{NAME} is the name of the variable bound in the code block
body.  @var{ASSIGN} is a literal value, such as a string,
a number, a reference to a table, a list, a literal example, another
code block---with or without arguments---or the results of evaluating
a code block.

Here are examples of passing values by reference:

@table @asis
@item table
A table named with a @samp{NAME} keyword.

@example
#+NAME: example-table
| 1 |
| 2 |
| 3 |
| 4 |

#+NAME: table-length
#+BEGIN_SRC emacs-lisp :var table=example-table
  (length table)
#+END_SRC

#+RESULTS: table-length
: 4
@end example

When passing a table, you can treat specially the row, or the
column, containing labels for the columns, or the rows, in the
table.

@cindex @samp{colnames}, header argument
The @samp{colnames} header argument accepts @samp{yes}, @samp{no}, or @samp{nil} values.
The default value is @samp{nil}: if an input table has column
names---because the second row is a horizontal rule---then Org
removes the column names, processes the table, puts back the column
names, and then writes the table to the results block.  Using @samp{yes},
Org does the same to the first row, even if the initial table does
not contain any horizontal rule.  When set to @samp{no}, Org does not
pre-process column names at all.

@example
#+NAME: less-cols
| a |
|---|
| b |
| c |

#+BEGIN_SRC python :var tab=less-cols :colnames nil
  return [[val + '*' for val in row] for row in tab]
#+END_SRC

#+RESULTS:
| a  |
|----|
| b* |
| c* |
@end example

@cindex @samp{rownames}, header argument
Similarly, the @samp{rownames} header argument can take two values: @samp{yes}
or @samp{no}.  When set to @samp{yes}, Org removes the first column, processes
the table, puts back the first column, and then writes the table to
the results block.  The default is @samp{no}, which means Org does not
pre-process the first column.  Note that Emacs Lisp code blocks
ignore @samp{rownames} header argument because of the ease of
table-handling in Emacs.

@example
#+NAME: with-rownames
| one | 1 | 2 | 3 | 4 |  5 |
| two | 6 | 7 | 8 | 9 | 10 |

#+BEGIN_SRC python :var tab=with-rownames :rownames yes
  return [[val + 10 for val in row] for row in tab]
#+END_SRC

#+RESULTS:
| one | 11 | 12 | 13 | 14 | 15 |
| two | 16 | 17 | 18 | 19 | 20 |
@end example

@item list
A simple named list.

@example
#+NAME: example-list
- simple
  - not
  - nested
- list

#+BEGIN_SRC emacs-lisp :var x=example-list
  (print x)
#+END_SRC

#+RESULTS:
| simple | list |
@end example

Note that only the top level list items are passed along.  Nested
list items are ignored.

@item code block without arguments
A code block name, as assigned by @samp{NAME} keyword from the example
above, optionally followed by parentheses.

@example
#+BEGIN_SRC emacs-lisp :var length=table-length()
  (* 2 length)
#+END_SRC

#+RESULTS:
: 8
@end example

@item code block with arguments
A code block name, as assigned by @samp{NAME} keyword, followed by
parentheses and optional arguments passed within the parentheses.

@example
#+NAME: double
#+BEGIN_SRC emacs-lisp :var input=8
  (* 2 input)
#+END_SRC

#+RESULTS: double
: 16

#+NAME: squared
#+BEGIN_SRC emacs-lisp :var input=double(input=1)
  (* input input)
#+END_SRC

#+RESULTS: squared
: 4
@end example

@item literal example
A literal example block named with a @samp{NAME} keyword.

@example
#+NAME: literal-example
#+BEGIN_EXAMPLE
  A literal example
  on two lines
#+END_EXAMPLE

#+NAME: read-literal-example
#+BEGIN_SRC emacs-lisp :var x=literal-example
  (concatenate #'string x " for you.")
#+END_SRC

#+RESULTS: read-literal-example
: A literal example
: on two lines for you.
@end example
@end table

Indexing variable values enables referencing portions of a variable.
Indexes are 0 based with negative values counting backwards from the
end.  If an index is separated by commas then each subsequent section
indexes as the next dimension.  Note that this indexing occurs
@emph{before} other table-related header arguments are applied, such as
@samp{hlines}, @samp{colnames} and @samp{rownames}.  The following example assigns
the last cell of the first row the table @samp{example-table} to the
variable @samp{data}:

@example
#+NAME: example-table
| 1 | a |
| 2 | b |
| 3 | c |
| 4 | d |

#+BEGIN_SRC emacs-lisp :var data=example-table[0,-1]
  data
#+END_SRC

#+RESULTS:
: a
@end example

Two integers separated by a colon reference a range of variable
values.  In that case the entire inclusive range is referenced.  For
example the following assigns the middle three rows of @samp{example-table}
to @samp{data}.

@example
#+NAME: example-table
| 1 | a |
| 2 | b |
| 3 | c |
| 4 | d |
| 5 | 3 |

#+BEGIN_SRC emacs-lisp :var data=example-table[1:3]
  data
#+END_SRC

#+RESULTS:
| 2 | b |
| 3 | c |
| 4 | d |
@end example

To pick the entire range, use an empty index, or the single character
@samp{*}.  @samp{0:-1} does the same thing.  Example below shows how to
reference the first column only.

@example
#+NAME: example-table
| 1 | a |
| 2 | b |
| 3 | c |
| 4 | d |

#+BEGIN_SRC emacs-lisp :var data=example-table[,0]
  data
#+END_SRC

#+RESULTS:
| 1 | 2 | 3 | 4 |
@end example

Index referencing can be used for tables and code blocks.  Index
referencing can handle any number of dimensions.  Commas delimit
multiple dimensions, as shown below.

@example
#+NAME: 3D
#+BEGIN_SRC emacs-lisp
  '(((1  2  3)  (4  5  6)  (7  8  9))
    ((10 11 12) (13 14 15) (16 17 18))
    ((19 20 21) (22 23 24) (25 26 27)))
#+END_SRC

#+BEGIN_SRC emacs-lisp :var data=3D[1,,1]
  data
#+END_SRC

#+RESULTS:
| 11 | 14 | 17 |
@end example

Note that row names and column names are not removed prior to variable
indexing.  You need to take them into account, even when @samp{colnames} or
@samp{rownames} header arguments remove them.

Emacs lisp code can also set the values for variables.  To
differentiate a value from Lisp code, Org interprets any value
starting with @samp{(}, @samp{[}, @samp{'} or @samp{`} as Emacs Lisp code.  The result of
evaluating that code is then assigned to the value of that variable.
The following example shows how to reliably query and pass the file
name of the Org mode buffer to a code block using headers.  We need
reliability here because the file's name could change once the code in
the block starts executing.

@example
#+BEGIN_SRC sh :var filename=(buffer-file-name) :exports both
  wc -w $filename
#+END_SRC
@end example

Note that values read from tables and lists are not mistakenly
evaluated as Emacs Lisp code, as illustrated in the following example.

@example
#+NAME: table
| (a b c) |

#+HEADER: :var data=table[0,0]
#+BEGIN_SRC perl
  $data
#+END_SRC

#+RESULTS:
: (a b c)
@end example

@anchor{Using sessions}
@subheading Using sessions

@cindex using sessions in code blocks
@cindex @samp{session}, header argument
Two code blocks can share the same environment.  The @samp{session} header
argument is for running multiple source code blocks under one session.
Org runs code blocks with the same session name in the same
interpreter process.

@table @asis
@item @samp{none}
Default.  Each code block gets a new interpreter process to execute.
The process terminates once the block is evaluated.

@item @var{STRING}
Any string besides @samp{none} turns that string into the name of that
session.  For example, @samp{:session STRING} names it @samp{STRING}.  If
@samp{session} has no value, then the session name is derived from the
source language identifier.  Subsequent blocks with the same source
code language use the same session.  Depending on the language,
state variables, code from other blocks, and the overall interpreted
environment may be shared.  Some interpreted languages support
concurrent sessions when subsequent source code language blocks
change session names.
@end table

Only languages that provide interactive evaluation can have session
support.  Not all languages provide this support, such as C and ditaa.
Even languages, such as Python and Haskell, that do support
interactive evaluation impose limitations on allowable language
constructs that can run interactively.  Org inherits those limitations
for those code blocks running in a session.

@anchor{Choosing a working directory}
@subheading Choosing a working directory

@cindex working directory, in a code block
@cindex @samp{dir}, header argument
@cindex @samp{mkdirp}, header argument
The @samp{dir} header argument specifies the default directory during code
block execution.  If it is absent, then the directory associated with
the current buffer is used.  In other words, supplying @samp{:dir
DIRECTORY} temporarily has the same effect as changing the current
directory with @kbd{M-x cd @key{RET} DIRECTORY}, and then not setting
@samp{dir}.  Under the surface, @samp{dir} simply sets the value of the Emacs
variable @code{default-directory}.  Setting @samp{mkdirp} header argument to
a non-@code{nil} value creates the directory, if necessary.

For example, to save the plot file in the @samp{Work/} folder of the home
directory---notice tilde is expanded:

@example
#+BEGIN_SRC R :file myplot.png :dir ~/Work
  matplot(matrix(rnorm(100), 10), type="l")
#+END_SRC
@end example

To evaluate the code block on a remote machine, supply a remote
directory name using Tramp syntax.  For example:

@example
#+BEGIN_SRC R :file plot.png :dir /scp:dand@@yakuba.princeton.edu:
  plot(1:10, main=system("hostname", intern=TRUE))
#+END_SRC
@end example

Org first captures the text results as usual for insertion in the Org
file.  Then Org also inserts a link to the remote file, thanks to
Emacs Tramp.  Org constructs the remote path to the file name from
@samp{dir} and @code{default-directory}, as illustrated here:

@example
[[file:/scp:dand@@yakuba.princeton.edu:/home/dand/plot.png][plot.png]]
@end example


When @samp{dir} is used with @samp{session}, Org sets the starting directory for
a new session.  But Org does not alter the directory of an already
existing session.

Do not use @samp{dir} with @samp{:exports results} or with @samp{:exports both} to
avoid Org inserting incorrect links to remote files.  That is because
Org does not expand @code{default directory} to avoid some underlying
portability issues.

@anchor{Inserting headers and footers}
@subheading Inserting headers and footers

@cindex headers, in code blocks
@cindex footers, in code blocks
@cindex @samp{prologue}, header argument
The @samp{prologue} header argument is for appending to the top of the code
block for execution, like a reset instruction.  For example, you may
use @samp{:prologue "reset"} in a Gnuplot code block or, for every such
block:

@lisp
(add-to-list 'org-babel-default-header-args:gnuplot
             '((:prologue . "reset")))

@end lisp

@cindex @samp{epilogue}, header argument
Likewise, the value of the @samp{epilogue} header argument is for appending
to the end of the code block for execution.

@node Evaluating Code Blocks
@section Evaluating Code Blocks

@cindex code block, evaluating
@cindex source code, evaluating
@cindex @samp{RESULTS}, keyword

A note about security: With code evaluation comes the risk of harm.
Org safeguards by prompting for user's permission before executing any
code in the source block.  To customize this safeguard, or disable it,
see @ref{Code Evaluation Security}.

@anchor{How to evaluate source code}
@subheading How to evaluate source code

Org captures the results of the code block evaluation and inserts them
in the Org file, right after the code block.  The insertion point is
after a newline and the @samp{RESULTS} keyword.  Org creates the @samp{RESULTS}
keyword if one is not already there.

By default, Org enables only Emacs Lisp code blocks for execution.
See @ref{Languages} to enable other languages.

@kindex C-c C-c
@kindex C-c C-v e
@findex org-babel-execute-src-block
Org provides many ways to execute code blocks.  @kbd{C-c C-c} or
@kbd{C-c C-v e} with the point on a code block@footnote{The option @code{org-babel-no-eval-on-ctrl-c-ctrl-c} can be used
to remove code evaluation from the @kbd{C-c C-c} key binding.} calls the
@code{org-babel-execute-src-block} function, which executes the code in the
block, collects the results, and inserts them in the buffer.

@cindex @samp{CALL}, keyword
@vindex org-babel-inline-result-wrap
By calling a named code block@footnote{Actually, the constructs @samp{call_<name>()} and @samp{src_<lang>@{@}}
are not evaluated when they appear in a keyword (see @ref{In-buffer Settings}).} from an Org mode buffer or
a table.  Org can call the named code blocks from the current Org mode
buffer or from the ``Library of Babel'' (see @ref{Library of Babel}).

The syntax for @samp{CALL} keyword is:

@example
#+CALL: <name>(<arguments>)
#+CALL: <name>[<inside header arguments>](<arguments>) <end header arguments>
@end example

The syntax for inline named code blocks is:

@example
... call_<name>(<arguments>) ...
... call_<name>[<inside header arguments>](<arguments>)[<end header arguments>] ...
@end example

When inline syntax is used, the result is wrapped based on the
variable @code{org-babel-inline-result-wrap}, which by default is set to
@code{"=%s="} to produce verbatim text suitable for markup.

@table @asis
@item @samp{<name>}
This is the name of the code block (see @ref{Structure of Code Blocks})
to be evaluated in the current document.  If the block is located in
another file, start @samp{<name>} with the file name followed by
a colon. For example, in order to execute a block named @samp{clear-data}
in @samp{file.org}, you can write the following:

@example
#+CALL: file.org:clear-data()
@end example

@item @samp{<arguments>}
Org passes arguments to the code block using standard function call
syntax.  For example, a @samp{#+CALL:} line that passes @samp{4} to a code
block named @samp{double}, which declares the header argument @samp{:var n=2},
would be written as:

@example
#+CALL: double(n=4)
@end example


@noindent
Note how this function call syntax is different from the header
argument syntax.

@item @samp{<inside header arguments>}
Org passes inside header arguments to the named code block using the
header argument syntax.  Inside header arguments apply to code block
evaluation.  For example, @samp{[:results output]} collects results
printed to stdout during code execution of that block.  Note how
this header argument syntax is different from the function call
syntax.

@item @samp{<end header arguments>}
End header arguments affect the results returned by the code block.
For example, @samp{:results html} wraps the results in a @samp{#+BEGIN_EXPORT
  html} block before inserting the results in the Org buffer.
@end table

@anchor{Limit code block evaluation}
@subheading Limit code block evaluation

@cindex @samp{eval}, header argument
@cindex control code block evaluation
The @samp{eval} header argument can limit evaluation of specific code
blocks and @samp{CALL} keyword.  It is useful for protection against
evaluating untrusted code blocks by prompting for a confirmation.

@table @asis
@item @samp{never} or @samp{no}
Org never evaluates the source code.

@item @samp{query}
Org prompts the user for permission to evaluate the source code.

@item @samp{never-export} or @samp{no-export}
Org does not evaluate the source code when exporting, yet the user
can evaluate it interactively.

@item @samp{query-export}
Org prompts the user for permission to evaluate the source code
during export.
@end table

If @samp{eval} header argument is not set, then Org determines whether to
evaluate the source code from the @code{org-confirm-babel-evaluate}
variable (see @ref{Code Evaluation Security}).

@anchor{Cache results of evaluation}
@subheading Cache results of evaluation

@cindex @samp{cache}, header argument
@cindex cache results of code evaluation
The @samp{cache} header argument is for caching results of evaluating code
blocks.  Caching results can avoid re-evaluating a code block that
have not changed since the previous run.  To benefit from the cache
and avoid redundant evaluations, the source block must have a result
already present in the buffer, and neither the header
arguments---including the value of @samp{var} references---nor the text of
the block itself has changed since the result was last computed.  This
feature greatly helps avoid long-running calculations.  For some edge
cases, however, the cached results may not be reliable.

The caching feature is best for when code blocks are pure functions,
that is functions that return the same value for the same input
arguments (see @ref{Environment of a Code Block}), and that do not have
side effects, and do not rely on external variables other than the
input arguments.  Functions that depend on a timer, file system
objects, and random number generators are clearly unsuitable for
caching.

A note of warning: when @samp{cache} is used in a session, caching may
cause unexpected results.

When the caching mechanism tests for any source code changes, it does
not expand Noweb style references (see @ref{Noweb Reference Syntax}).  For
reasons why, see @uref{http://thread.gmane.org/gmane.emacs.orgmode/79046}.

The @samp{cache} header argument can have one of two values: @samp{yes} or @samp{no}.

@table @asis
@item @samp{no}
Default.  No caching of results; code block evaluated every time.

@item @samp{yes}
Whether to run the code or return the cached results is determined
by comparing the SHA1 hash value of the combined code block and
arguments passed to it.  This hash value is packed on the
@samp{#+RESULTS:} line from previous evaluation.  When hash values match,
Org does not evaluate the code block.  When hash values mismatch,
Org evaluates the code block, inserts the results, recalculates the
hash value, and updates @samp{#+RESULTS:} line.
@end table

In this example, both functions are cached.  But @samp{caller} runs only if
the result from @samp{random} has changed since the last run.

@example
#+NAME: random
#+BEGIN_SRC R :cache yes
  runif(1)
#+END_SRC

#+RESULTS[a2a72cd647ad44515fab62e144796432793d68e1]: random
0.4659510825295

#+NAME: caller
#+BEGIN_SRC emacs-lisp :var x=random :cache yes
  x
#+END_SRC

#+RESULTS[bec9c8724e397d5df3b696502df3ed7892fc4f5f]: caller
0.254227238707244
@end example

@node Results of Evaluation
@section Results of Evaluation

@cindex code block, results of evaluation
@cindex source code, results of evaluation

@cindex @samp{results}, header argument
How Org handles results of a code block execution depends on many
header arguments working together.  The primary determinant, however,
is the @samp{results} header argument.  It accepts four classes of options.
Each code block can take only one option per class:

@table @asis
@item Collection
For how the results should be collected from the code block;

@item Type
For which type of result the code block will return; affects how Org
processes and inserts results in the Org buffer;

@item Format
For the result; affects how Org processes results;

@item Handling
For inserting results once they are properly formatted.
@end table

@anchor{Collection}
@subheading Collection

Collection options specify the results.  Choose one of the options;
they are mutually exclusive.

@table @asis
@item @samp{value}
Default.  Functional mode.  Org gets the value by wrapping the code
in a function definition in the language of the source block.  That
is why when using @samp{:results value}, code should execute like
a function and return a value.  For languages like Python, an
explicit @code{return} statement is mandatory when using @samp{:results
  value}.  Result is the value returned by the last statement in the
code block.

When evaluating the code block in a session (see @ref{Environment of a Code Block}), Org passes the code to an interpreter running as an
interactive Emacs inferior process. Org gets the value from the
source code interpreter's last statement output.  Org has to use
language-specific methods to obtain the value.  For example, from
the variable @code{_} in Python and Ruby, and the value of @code{.Last.value}
in R@.

@item @samp{output}
Scripting mode.  Org passes the code to an external process running
the interpreter.  Org returns the contents of the standard output
stream as text results.

When using a session, Org passes the code to the interpreter running
as an interactive Emacs inferior process.  Org concatenates any text
output from the interpreter and returns the collection as a result.

Note that this collection is not the same as that would be collected
from stdout of a non-interactive interpreter running as an external
process.  Compare for example these two blocks:

@example
#+BEGIN_SRC python :results output
  print "hello"
  2
  print "bye"
#+END_SRC

#+RESULTS:
: hello
: bye
@end example

In the above non-session mode, the ``2'' is not printed; so it does
not appear in results.

@example
#+BEGIN_SRC python :results output :session
  print "hello"
  2
  print "bye"
#+END_SRC

#+RESULTS:
: hello
: 2
: bye
@end example

In the above session, the interactive interpreter receives and
prints ``2''.  Results show that.
@end table

@anchor{Type}
@subheading Type

Type tells what result types to expect from the execution of the code
block.  Choose one of the options; they are mutually exclusive.  The
default behavior is to automatically determine the result type.

@table @asis
@item @samp{table}
@itemx @samp{vector}
Interpret the results as an Org table.  If the result is a single
value, create a table with one row and one column.  Usage example:
@samp{:results value table}.

@cindex @samp{hlines}, header argument
In-between each table row or below the table headings, sometimes
results have horizontal lines, which are also known as ``hlines''.
The @samp{hlines} argument with the default @samp{no} value strips such lines
from the input table.  For most code, this is desirable, or else
those @samp{hline} symbols raise unbound variable errors.  A @samp{yes}
accepts such lines, as demonstrated in the following example.

@example
#+NAME: many-cols
| a | b | c |
|---+---+---|
| d | e | f |
|---+---+---|
| g | h | i |

#+NAME: no-hline
#+BEGIN_SRC python :var tab=many-cols :hlines no
  return tab
#+END_SRC

#+RESULTS: no-hline
| a | b | c |
| d | e | f |
| g | h | i |

#+NAME: hlines
#+BEGIN_SRC python :var tab=many-cols :hlines yes
  return tab
#+END_SRC

#+RESULTS: hlines
| a | b | c |
|---+---+---|
| d | e | f |
|---+---+---|
| g | h | i |
@end example

@item @samp{list}
Interpret the results as an Org list.  If the result is a single
value, create a list of one element.

@item @samp{scalar}
@itemx @samp{verbatim}
Interpret literally and insert as quoted text.  Do not create
a table.  Usage example: @samp{:results value verbatim}.

@item @samp{file}
Interpret as a filename.  Save the results of execution of the code
block to that file, then insert a link to it.  You can control both
the filename and the description associated to the link.

@cindex @samp{file}, header argument
@cindex @samp{output-dir}, header argument
Org first tries to generate the filename from the value of the
@samp{file} header argument and the directory specified using the
@samp{output-dir} header arguments.  If @samp{output-dir} is not specified,
Org assumes it is the current directory.

@example
#+BEGIN_SRC asymptote :results value file :file circle.pdf :output-dir img/
  size(2cm);
  draw(unitcircle);
#+END_SRC
@end example

@cindex @samp{file-ext}, header argument
If @samp{file} header argument is missing, Org generates the base name of
the output file from the name of the code block, and its extension
from the @samp{file-ext} header argument.  In that case, both the name
and the extension are mandatory.

@example
#+name: circle
#+BEGIN_SRC asymptote :results value file :file-ext pdf
  size(2cm);
  draw(unitcircle);
#+END_SRC
@end example

@cindex @samp{file-desc}, header argument
The @samp{file-desc} header argument defines the description (see
@ref{Link Format}) for the link.  If @samp{file-desc} has no value, Org
uses the generated file name for both the ``link'' and
``description'' parts of the link.

@cindex @samp{sep}, header argument
By default, Org assumes that a table written to a file has
TAB-delimited output.  You can choose a different separator with
the @samp{sep} header argument.
@end table

@anchor{Format}
@subheading Format

Format pertains to the type of the result returned by the code block.
Choose one of the options; they are mutually exclusive.  The default
follows from the type specified above.

@table @asis
@item @samp{code}
Result enclosed in a code block.  Useful for parsing.  Usage
example: @samp{:results value code}.

@item @samp{drawer}
Result wrapped in a @samp{RESULTS} drawer.  Useful for containing @samp{raw}
or @samp{org} results for later scripting and automated processing.
Usage example: @samp{:results value drawer}.

@item @samp{html}
Results enclosed in a @samp{BEGIN_EXPORT html} block.  Usage example:
@samp{:results value html}.

@item @samp{latex}
Results enclosed in a @samp{BEGIN_EXPORT latex} block.  Usage example:
@samp{:results value latex}.

@item @samp{link}
@itemx @samp{graphics}
Result is a link to the file specified in @samp{:file} header argument.
However, unlike plain @samp{:file}, nothing is written to the disk.  The
block is used for its side-effects only, as in the following
example:

@example
#+begin_src shell :results link :file "download.tar.gz"
wget -c "http://example.com/download.tar.gz"
#+end_src
@end example

@item @samp{org}
Results enclosed in a @samp{BEGIN_SRC org} block.  For comma-escape,
either @kbd{@key{TAB}} in the block, or export the file.  Usage
example: @samp{:results value org}.

@item @samp{pp}
Result converted to pretty-print source code.  Enclosed in a code
block.  Languages supported: Emacs Lisp, Python, and Ruby.  Usage
example: @samp{:results value pp}.

@item @samp{raw}
Interpreted as raw Org mode.  Inserted directly into the buffer.
Aligned if it is a table.  Usage example: @samp{:results value raw}.
@end table

@cindex @samp{wrap}, header argument
The @samp{wrap} header argument unconditionally marks the results block by
appending strings to @samp{#+BEGIN_} and @samp{#+END_}.  If no string is
specified, Org wraps the results in a @samp{#+BEGIN_results}
@dots{} @samp{#+END_results} block.  It takes precedent over the @samp{results}
value listed above.  E.g.,

@example
#+BEGIN_SRC emacs-lisp :results html :wrap EXPORT markdown
"<blink>Welcome back to the 90's</blink>"
#+END_SRC

#+RESULTS:
#+BEGIN_EXPORT markdown
<blink>Welcome back to the 90's</blink>
#+END_EXPORT
@end example

@anchor{Handling}
@subheading Handling

Handling options after collecting the results.

@table @asis
@item @samp{silent}
Do not insert results in the Org mode buffer, but echo them in the
minibuffer.  Usage example: @samp{:results output silent}.

@item @samp{replace}
Default.  Insert results in the Org buffer.  Remove previous
results.  Usage example: @samp{:results output replace}.

@item @samp{append}
Append results to the Org buffer.  Latest results are at the bottom.
Does not remove previous results.  Usage example: @samp{:results output
  append}.

@item @samp{prepend}
Prepend results to the Org buffer.  Latest results are at the top.
Does not remove previous results.  Usage example: @samp{:results output
  prepend}.
@end table

@anchor{Post-processing}
@subheading Post-processing

@cindex @samp{post}, header argument
@cindex @samp{*this*}, in @samp{post} header argument
The @samp{post} header argument is for post-processing results from block
evaluation.  When @samp{post} has any value, Org binds the results to
@code{*this*} variable for easy passing to @samp{var} header argument
specifications (see @ref{Environment of a Code Block}).  That makes results
available to other code blocks, or even for direct Emacs Lisp code
execution.

The following two examples illustrate @samp{post} header argument in
action.  The first one shows how to attach an @samp{ATTR_LATEX} keyword
using @samp{post}.

@example
#+NAME: attr_wrap
#+BEGIN_SRC sh :var data="" :var width="\\textwidth" :results output
  echo "#+ATTR_LATEX: :width $width"
  echo "$data"
#+END_SRC

#+HEADER: :file /tmp/it.png
#+BEGIN_SRC dot :post attr_wrap(width="5cm", data=*this*) :results drawer
  digraph@{
          a -> b;
          b -> c;
          c -> a;
  @}
#+end_src

#+RESULTS:
:RESULTS:
#+ATTR_LATEX :width 5cm
[[file:/tmp/it.png]]
:END:
@end example

The second example shows use of @samp{colnames} header argument in @samp{post}
to pass data between code blocks.

@example
#+NAME: round-tbl
#+BEGIN_SRC emacs-lisp :var tbl="" fmt="%.3f"
  (mapcar (lambda (row)
            (mapcar (lambda (cell)
                      (if (numberp cell)
                          (format fmt cell)
                        cell))
                    row))
          tbl)
#+end_src

#+BEGIN_SRC R :colnames yes :post round-tbl[:colnames yes](*this*)
  set.seed(42)
  data.frame(foo=rnorm(1))
#+END_SRC

#+RESULTS:
|   foo |
|-------|
| 1.371 |
@end example

@node Exporting Code Blocks
@section Exporting Code Blocks

@cindex code block, exporting
@cindex source code, exporting

It is possible to export the @emph{code} of code blocks, the @emph{results} of
code block evaluation, @emph{both} the code and the results of code block
evaluation, or @emph{none}.  Org defaults to exporting @emph{code} for most
languages.  For some languages, such as ditaa, Org defaults to
@emph{results}.  To export just the body of code blocks, see @ref{Literal Examples}.  To selectively export sub-trees of an Org document, see
@ref{Exporting}.

@cindex @samp{exports}, header argument
The @samp{exports} header argument is to specify if that part of the Org
file is exported to, say, HTML or @LaTeX{} formats.

@table @asis
@item @samp{code}
The default.  The body of code is included into the exported file.
Example: @samp{:exports code}.

@item @samp{results}
The results of evaluation of the code is included in the exported
file.  Example: @samp{:exports results}.

@item @samp{both}
Both the code and results of evaluation are included in the exported
file.  Example: @samp{:exports both}.

@item @samp{none}
Neither the code nor the results of evaluation is included in the
exported file.  Whether the code is evaluated at all depends on
other options.  Example: @samp{:exports none}.
@end table

@vindex org-export-use-babel
To stop Org from evaluating code blocks to speed exports, use the
header argument @samp{:eval never-export} (see @ref{Evaluating Code Blocks}).
To stop Org from evaluating code blocks for greater security, set the
@code{org-export-use-babel} variable to @code{nil}, but understand that header
arguments will have no effect.

Turning off evaluation comes in handy when batch processing.  For
example, markup languages for wikis, which have a high risk of
untrusted code.  Stopping code block evaluation also stops evaluation
of all header arguments of the code block.  This may not be desirable
in some circumstances.  So during export, to allow evaluation of just
the header arguments but not any code evaluation in the source block,
set @samp{:eval never-export} (see @ref{Evaluating Code Blocks}).

Org never evaluates code blocks in commented sub-trees when exporting
(see @ref{Comment Lines}).  On the other hand, Org does evaluate code
blocks in sub-trees excluded from export (see @ref{Export Settings}).

@node Extracting Source Code
@section Extracting Source Code

@cindex tangling
@cindex source code, extracting
@cindex code block, extracting source code

Extracting source code from code blocks is a basic task in literate
programming.  Org has features to make this easy.  In literate
programming parlance, documents on creation are @emph{woven} with code and
documentation, and on export, the code is tangled for execution by
a computer.  Org facilitates weaving and tangling for producing,
maintaining, sharing, and exporting literate programming documents.
Org provides extensive customization options for extracting source
code.

When Org tangles code blocks, it expands, merges, and transforms them.
Then Org recomposes them into one or more separate files, as
configured through the options.  During this tangling process, Org
expands variables in the source code, and resolves any Noweb style
references (see @ref{Noweb Reference Syntax}).

@anchor{Header arguments}
@subheading Header arguments

@cindex @samp{tangle}, header argument
The @samp{tangle} header argument specifies if the code block is exported
to source file(s).

@table @asis
@item @samp{yes}
Export the code block to source file.  The file name for the source
file is derived from the name of the Org file, and the file
extension is derived from the source code language identifier.
Example: @samp{:tangle yes}.

@item @samp{no}
The default.  Do not extract the code in a source code file.
Example: @samp{:tangle no}.

@item @var{FILENAME}
Export the code block to source file whose file name is derived from
any string passed to the @samp{tangle} header argument.  Org derives the
file name as being relative to the directory of the Org file's
location.  Example: @samp{:tangle FILENAME}.
@end table

@cindex @samp{mkdirp}, header argument
The @samp{mkdirp} header argument creates parent directories for tangled
files if the directory does not exist.  A @samp{yes} value enables
directory creation whereas @samp{no} inhibits it.

@cindex @samp{comments}, header argument
The @samp{comments} header argument controls inserting comments into
tangled files.  These are above and beyond whatever comments may
already exist in the code block.

@table @asis
@item @samp{no}
The default.  Do not insert any extra comments during tangling.

@item @samp{link}
Wrap the code block in comments.  Include links pointing back to the
place in the Org file from where the code was tangled.

@item @samp{yes}
Kept for backward compatibility; same as @samp{link}.

@item @samp{org}
Nearest headline text from Org file is inserted as comment.  The
exact text that is inserted is picked from the leading context of
the source block.

@item @samp{both}
Includes both @samp{link} and @samp{org} options.

@item @samp{noweb}
Includes @samp{link} option, expands Noweb references (see @ref{Noweb Reference Syntax}), and wraps them in link comments inside the body
of the code block.
@end table

@cindex @samp{padline}, header argument
The @samp{padline} header argument controls insertion of newlines to pad
source code in the tangled file.

@table @asis
@item @samp{yes}
Default.  Insert a newline before and after each code block in the
tangled file.

@item @samp{no}
Do not insert newlines to pad the tangled code blocks.
@end table

@cindex @samp{shebang}, header argument
The @samp{shebang} header argument can turn results into executable script
files.  By setting it to a string value---for example, @samp{:shebang
"#!/bin/bash"}---Org inserts that string as the first line of the
tangled file that the code block is extracted to.  Org then turns on
the tangled file's executable permission.

@cindex @samp{tangle-mode}, header argument
The @samp{tangle-mode} header argument specifies what permissions to set
for tangled files by @code{set-file-modes}.  For example, to make
a read-only tangled file, use @samp{:tangle-mode (identity #o444)}.  To
make it executable, use @samp{:tangle-mode (identity #o755)}.  It also
overrides executable permission granted by @samp{shebang}.  When multiple
source code blocks tangle to a single file with different and
conflicting @samp{tangle-mode} header arguments, Org's behavior is
undefined.

@cindex @samp{no-expand}, header argument
By default Org expands code blocks during tangling.  The @samp{no-expand}
header argument turns off such expansions.  Note that one side-effect
of expansion by @code{org-babel-expand-src-block} also assigns values (see
@ref{Environment of a Code Block}) to variables.  Expansions also replace
Noweb references with their targets (see @ref{Noweb Reference Syntax}).
Some of these expansions may cause premature assignment, hence this
option.  This option makes a difference only for tangling.  It has no
effect when exporting since code blocks for execution have to be
expanded anyway.

@anchor{Functions}
@subheading Functions

@table @asis
@item @code{org-babel-tangle}
@findex org-babel-tangle
@kindex C-c C-v t
Tangle the current file.  Bound to @kbd{C-c C-v t}.

With prefix argument only tangle the current code block.

@item @code{org-babel-tangle-file}
@findex org-babel-tangle-file
@kindex C-c C-v f
Choose a file to tangle.  Bound to @kbd{C-c C-v f}.
@end table

@anchor{Hooks (1)}
@subheading Hooks

@table @asis
@item @code{org-babel-post-tangle-hook}
@vindex org-babel-post-tangle-hook
This hook is run from within code files tangled by
@code{org-babel-tangle}, making it suitable for post-processing,
compilation, and evaluation of code in the tangled files.
@end table

@anchor{Jumping between code and Org}
@subheading Jumping between code and Org

@findex org-babel-tangle-jump-to-org
Debuggers normally link errors and messages back to the source code.
But for tangled files, we want to link back to the Org file, not to
the tangled source file.  To make this extra jump, Org uses
@code{org-babel-tangle-jump-to-org} function with two additional source
code block header arguments:

@enumerate
@item
Set @samp{padline} to true---this is the default setting.
@item
Set @samp{comments} to @samp{link}, which makes Org insert links to the Org
file.
@end enumerate

@node Languages
@section Languages

@cindex babel, languages
@cindex source code, languages
@cindex code block, languages

Code blocks in the following languages are supported.

@multitable @columnfractions 0.20 0.35 0.20 0.20
@headitem Language
@tab Identifier
@tab Language
@tab Identifier
@item Asymptote
@tab @samp{asymptote}
@tab Lisp
@tab @samp{lisp}
@item Awk
@tab @samp{awk}
@tab Lua
@tab @samp{lua}
@item C
@tab @samp{C}
@tab MATLAB
@tab @samp{matlab}
@item C++
@tab @samp{C++}@footnote{C++ language is handled in @samp{ob-C.el}.  Even though the
identifier for such source blocks is @samp{C++}, you activate it by loading
the C language.}
@tab Mscgen
@tab @samp{mscgen}
@item Clojure
@tab @samp{clojure}
@tab Objective Caml
@tab @samp{ocaml}
@item CSS
@tab @samp{css}
@tab Octave
@tab @samp{octave}
@item D
@tab @samp{D}@footnote{D language is handled in @samp{ob-C.el}.  Even though the
identifier for such source blocks is @samp{D}, you activate it by loading
the C language.}
@tab Org mode
@tab @samp{org}
@item ditaa
@tab @samp{ditaa}
@tab Oz
@tab @samp{oz}
@item Emacs Calc
@tab @samp{calc}
@tab Perl
@tab @samp{perl}
@item Emacs Lisp
@tab @samp{emacs-lisp}
@tab Plantuml
@tab @samp{plantuml}
@item Eshell
@tab @samp{eshell}
@tab Processing.js
@tab @samp{processing}
@item Fortran
@tab @samp{fortran}
@tab Python
@tab @samp{python}
@item Gnuplot
@tab @samp{gnuplot}
@tab R
@tab @samp{R}
@item GNU Screen
@tab @samp{screen}
@tab Ruby
@tab @samp{ruby}
@item Graphviz
@tab @samp{dot}
@tab Sass
@tab @samp{sass}
@item Haskell
@tab @samp{haskell}
@tab Scheme
@tab @samp{scheme}
@item Java
@tab @samp{java}
@tab Sed
@tab @samp{sed}
@item Javascript
@tab @samp{js}
@tab shell
@tab @samp{sh}
@item @LaTeX{}
@tab @samp{latex}
@tab SQL
@tab @samp{sql}
@item Ledger
@tab @samp{ledger}
@tab SQLite
@tab @samp{sqlite}
@item Lilypond
@tab @samp{lilypond}
@tab Vala
@tab @samp{vala}
@end multitable

Additional documentation for some languages is at
@uref{https://orgmode.org/worg/org-contrib/babel/languages.html}.

@vindex org-babel-load-languages
By default, only Emacs Lisp is enabled for evaluation.  To enable or
disable other languages, customize the @code{org-babel-load-languages}
variable either through the Emacs customization interface, or by
adding code to the init file as shown next.

In this example, evaluation is disabled for Emacs Lisp, and enabled
for R@.

@lisp
(org-babel-do-load-languages
 'org-babel-load-languages
 '((emacs-lisp . nil)
   (R . t)))
@end lisp

Note that this is not the only way to enable a language.  Org also
enables languages when loaded with @code{require} statement.  For example,
the following enables execution of Clojure code blocks:

@lisp
(require 'ob-clojure)
@end lisp

@node Editing Source Code
@section Editing Source Code

@cindex code block, editing
@cindex source code, editing

@kindex C-c '
Use @kbd{C-c '} to edit the current code block.  It opens a new
major mode edit buffer containing the body of the source code block,
ready for any edits.  Use @kbd{C-c '} again to close the buffer
and return to the Org buffer.

@kindex C-x C-s
@vindex org-edit-src-auto-save-idle-delay
@cindex auto-save, in code block editing
@kbd{C-x C-s} saves the buffer and updates the contents of the
Org buffer.  Set @code{org-edit-src-auto-save-idle-delay} to save the base
buffer after a certain idle delay time.  Set
@code{org-edit-src-turn-on-auto-save} to auto-save this buffer into
a separate file using Auto-save mode.

While editing the source code in the major mode, the Org Src minor
mode remains active.  It provides these customization variables as
described below.  For even more variables, look in the customization
group @code{org-edit-structure}.

@table @asis
@item @code{org-src-lang-modes}
@vindex org-src-lang-modes
If an Emacs major-mode named @code{<LANG>-mode} exists, where
@var{<LANG>} is the language identifier from code block's
header line, then the edit buffer uses that major mode.  Use this
variable to arbitrarily map language identifiers to major modes.

@item @code{org-src-window-setup}
@vindex org-src-window-setup
For specifying Emacs window arrangement when the new edit buffer is
created.

@item @code{org-src-preserve-indentation}
@cindex indentation, in code blocks
@vindex org-src-preserve-indentation
Default is @code{nil}.  Source code is indented.  This indentation
applies during export or tangling, and depending on the context, may
alter leading spaces and tabs.  When non-@code{nil}, source code is
aligned with the leftmost column.  No lines are modified during
export or tangling, which is very useful for white-space sensitive
languages, such as Python.

@item @code{org-src-ask-before-returning-to-edit-buffer}
@vindex org-src-ask-before-returning-to-edit-buffer
When @code{nil}, Org returns to the edit buffer without further prompts.
The default prompts for a confirmation.
@end table

@vindex org-src-fontify-natively
@vindex org-src-block-faces
Set @code{org-src-fontify-natively} to non-@code{nil} to turn on native code
fontification in the @emph{Org} buffer.  Fontification of code blocks can
give visual separation of text and code on the display page.  To
further customize the appearance of @code{org-block} for specific
languages, customize @code{org-src-block-faces}.  The following example
shades the background of regular blocks, and colors source blocks only
for Python and Emacs Lisp languages.

@lisp
(require 'color)
(set-face-attribute 'org-block nil :background
                    (color-darken-name
                     (face-attribute 'default :background) 3))

(setq org-src-block-faces '(("emacs-lisp" (:background "#EEE2FF"))
                            ("python" (:background "#E5FFB8"))))
@end lisp

@node Noweb Reference Syntax
@section Noweb Reference Syntax

@cindex code block, Noweb reference
@cindex syntax, Noweb
@cindex source code, Noweb reference

Org supports named blocks in Noweb@footnote{For Noweb literate programming details, see
@uref{http://www.cs.tufts.edu/~nr/noweb/}.} style syntax:

@example
<<CODE-BLOCK-ID>>
@end example


Org can replace the construct with the source code, or the results of
evaluation, of the code block identified as @var{CODE-BLOCK-ID}.

@cindex @samp{noweb}, header argument
The @samp{noweb} header argument controls expansion of Noweb syntax
references.  Expansions occur when source code blocks are evaluated,
tangled, or exported.

@table @asis
@item @samp{no}
Default.  No expansion of Noweb syntax references in the body of the
code when evaluating, tangling, or exporting.

@item @samp{yes}
Expansion of Noweb syntax references in the body of the code block
when evaluating, tangling, or exporting.

@item @samp{tangle}
Expansion of Noweb syntax references in the body of the code block
when tangling.  No expansion when evaluating or exporting.

@item @samp{no-export}
Expansion of Noweb syntax references in the body of the code block
when evaluating or tangling.  No expansion when exporting.

@item @samp{strip-export}
Expansion of Noweb syntax references in the body of the code block
when expanding prior to evaluating or tangling.  Removes Noweb
syntax references when exporting.

@item @samp{eval}
Expansion of Noweb syntax references in the body of the code block
only before evaluating.
@end table

In the following example,

@example
#+NAME: initialization
#+BEGIN_SRC emacs-lisp
  (setq sentence "Never a foot too far, even.")
#+END_SRC

#+BEGIN_SRC emacs-lisp :noweb yes
  <<initialization>>
  (reverse sentence)
#+END_SRC
@end example

@noindent
the second code block is expanded as

@example
#+BEGIN_SRC emacs-lisp :noweb yes
  (setq sentence "Never a foot too far, even.")
  (reverse sentence)
#+END_SRC
@end example

Noweb insertions honor prefix characters that appear before the Noweb
syntax reference.  This behavior is illustrated in the following
example.  Because the @samp{<<example>>} Noweb reference appears behind the
SQL comment syntax, each line of the expanded Noweb reference is
commented.  With:

@example
#+NAME: example
#+BEGIN_SRC text
  this is the
  multi-line body of example
#+END_SRC
@end example

@noindent
this code block:

@example
#+BEGIN_SRC sql :noweb yes
 ---<<example>>
#+END_SRC
@end example

@noindent
expands to:

@example
#+BEGIN_SRC sql :noweb yes
 ---this is the
 ---multi-line body of example
#+END_SRC
@end example

Since this change does not affect Noweb replacement text without
newlines in them, inline Noweb references are acceptable.

This feature can also be used for management of indentation in
exported code snippets.  With:

@example
#+NAME: if-true
#+BEGIN_SRC python :exports none
  print('do things when true')
#+end_src

#+name: if-false
#+begin_src python :exports none
  print('do things when false')
#+end_src
@end example

@noindent
this code block:

@example
#+begin_src python :noweb yes :results output
  if true:
      <<if-true>>
  else:
      <<if-false>>
#+end_src
@end example

@noindent
expands to:

@example
if true:
    print('do things when true')
else:
    print('do things when false')
@end example

@cindex @samp{noweb-ref}, header argument
When expanding Noweb style references, Org concatenates code blocks by
matching the reference name to either the code block name or, if none
is found, to the @samp{noweb-ref} header argument.

For simple concatenation, set this @samp{noweb-ref} header argument at the
sub-tree or file level.  In the example Org file shown next, the body
of the source code in each block is extracted for concatenation to
a pure code file when tangled.

@example
#+BEGIN_SRC sh :tangle yes :noweb yes :shebang #!/bin/sh
  <<fullest-disk>>
#+END_SRC
* the mount point of the fullest disk
  :PROPERTIES:
  :header-args: :noweb-ref fullest-disk
  :END:

** query all mounted disks
#+BEGIN_SRC sh
  df \
#+END_SRC

** strip the header row
#+BEGIN_SRC sh
  |sed '1d' \
#+END_SRC

** output mount point of fullest disk
#+BEGIN_SRC sh
  |awk '@{if (u < +$5) @{u = +$5; m = $6@}@} END @{print m@}'
#+END_SRC
@end example

@cindex @samp{noweb-sep}, header argument
By default a newline separates each noweb reference concatenation.  To
change this newline separator, edit the @samp{noweb-sep} header argument.

Eventually, Org can include the results of a code block rather than
its body.  To that effect, append parentheses, possibly including
arguments, to the code block name, as shown below.

@example
<<code-block-name(optional arguments)>>
@end example


Note that when using the above approach to a code block's results, the
code block name set by @samp{NAME} keyword is required; the reference set
by @samp{noweb-ref} does not work in that case.

Here is an example that demonstrates how the exported content changes
when Noweb style references are used with parentheses versus without.
With:

@example
#+NAME: some-code
#+BEGIN_SRC python :var num=0 :results output :exports none
  print(num*10)
#+END_SRC
@end example

@noindent
this code block:

@example
#+BEGIN_SRC text :noweb yes
  <<some-code>>
#+END_SRC
@end example

@noindent
expands to:

@example
print(num*10)
@end example


Below, a similar Noweb style reference is used, but with parentheses,
while setting a variable @samp{num} to 10:

@example
#+BEGIN_SRC text :noweb yes
  <<some-code(num=10)>>
#+END_SRC
@end example

@noindent
Note that now the expansion contains the results of the code block
@samp{some-code}, not the code block itself:

@example
100
@end example

@node Library of Babel
@section Library of Babel

@cindex babel, library of
@cindex source code, library
@cindex code block, library

The ``Library of Babel'' is a collection of code blocks.  Like
a function library, these code blocks can be called from other Org
files.  A collection of useful code blocks is available on @uref{https://orgmode.org/worg/library-of-babel.html, Worg}.  For
remote code block evaluation syntax, see @ref{Evaluating Code Blocks}.

@kindex C-c C-v i
@findex org-babel-lob-ingest
For any user to add code to the library, first save the code in
regular code blocks of an Org file, and then load the Org file with
@code{org-babel-lob-ingest}, which is bound to @kbd{C-c C-v i}.

@node Key bindings and Useful Functions
@section Key bindings and Useful Functions

@cindex code block, key bindings

Many common Org mode key sequences are re-bound depending on
the context.

Active key bindings in code blocks:

@kindex C-c C-c
@findex org-babel-execute-src-block
@kindex C-c C-o
@findex org-babel-open-src-block-result
@kindex M-UP
@findex org-babel-load-in-session
@kindex M-DOWN
@findex org-babel-pop-to-session
@multitable @columnfractions 0.2 0.55
@headitem Key binding
@tab Function
@item @kbd{C-c C-c}
@tab @code{org-babel-execute-src-block}
@item @kbd{C-c C-o}
@tab @code{org-babel-open-src-block-result}
@item @kbd{M-@key{UP}}
@tab @code{org-babel-load-in-session}
@item @kbd{M-@key{DOWN}}
@tab @code{org-babel-pop-to-session}
@end multitable

Active key bindings in Org mode buffer:

@kindex C-c C-v p
@kindex C-c C-v C-p
@kindex C-c C-v n
@kindex C-c C-v C-n
@kindex C-c C-v e
@kindex C-c C-v C-e
@kindex C-c C-v o
@kindex C-c C-v C-o
@kindex C-c C-v v
@kindex C-c C-v C-v
@kindex C-c C-v u
@kindex C-c C-v C-u
@kindex C-c C-v g
@kindex C-c C-v C-g
@kindex C-c C-v r
@kindex C-c C-v C-r
@kindex C-c C-v b
@kindex C-c C-v C-b
@kindex C-c C-v s
@kindex C-c C-v C-s
@kindex C-c C-v d
@kindex C-c C-v C-d
@kindex C-c C-v t
@kindex C-c C-v C-t
@kindex C-c C-v f
@kindex C-c C-v C-f
@kindex C-c C-v c
@kindex C-c C-v C-c
@kindex C-c C-v j
@kindex C-c C-v C-j
@kindex C-c C-v l
@kindex C-c C-v C-l
@kindex C-c C-v i
@kindex C-c C-v C-i
@kindex C-c C-v I
@kindex C-c C-v C-I
@kindex C-c C-v z
@kindex C-c C-v C-z
@kindex C-c C-v a
@kindex C-c C-v C-a
@kindex C-c C-v h
@kindex C-c C-v C-h
@kindex C-c C-v x
@kindex C-c C-v C-x
@findex org-babel-previous-src-block
@findex org-babel-next-src-block
@findex org-babel-execute-maybe
@findex org-babel-open-src-block-result
@findex org-babel-expand-src-block
@findex org-babel-goto-src-block-head
@findex org-babel-goto-named-src-block
@findex org-babel-goto-named-result
@findex org-babel-execute-buffer
@findex org-babel-execute-subtree
@findex org-babel-demarcate-block
@findex org-babel-tangle
@findex org-babel-tangle-file
@findex org-babel-check-src-block
@findex org-babel-insert-header-arg
@findex org-babel-load-in-session
@findex org-babel-lob-ingest
@findex org-babel-view-src-block-info
@findex org-babel-switch-to-session-with-code
@findex org-babel-sha1-hash
@findex org-babel-describe-bindings
@findex org-babel-do-key-sequence-in-edit-buffer
@multitable @columnfractions 0.45 0.55
@headitem Key binding
@tab Function
@item @kbd{C-c C-v p} or @kbd{C-c C-v C-p}
@tab @code{org-babel-previous-src-block}
@item @kbd{C-c C-v n} or @kbd{C-c C-v C-n}
@tab @code{org-babel-next-src-block}
@item @kbd{C-c C-v e} or @kbd{C-c C-v C-e}
@tab @code{org-babel-execute-maybe}
@item @kbd{C-c C-v o} or @kbd{C-c C-v C-o}
@tab @code{org-babel-open-src-block-result}
@item @kbd{C-c C-v v} or @kbd{C-c C-v C-v}
@tab @code{org-babel-expand-src-block}
@item @kbd{C-c C-v u} or @kbd{C-c C-v C-u}
@tab @code{org-babel-goto-src-block-head}
@item @kbd{C-c C-v g} or @kbd{C-c C-v C-g}
@tab @code{org-babel-goto-named-src-block}
@item @kbd{C-c C-v r} or @kbd{C-c C-v C-r}
@tab @code{org-babel-goto-named-result}
@item @kbd{C-c C-v b} or @kbd{C-c C-v C-b}
@tab @code{org-babel-execute-buffer}
@item @kbd{C-c C-v s} or @kbd{C-c C-v C-s}
@tab @code{org-babel-execute-subtree}
@item @kbd{C-c C-v d} or @kbd{C-c C-v C-d}
@tab @code{org-babel-demarcate-block}
@item @kbd{C-c C-v t} or @kbd{C-c C-v C-t}
@tab @code{org-babel-tangle}
@item @kbd{C-c C-v f} or @kbd{C-c C-v C-f}
@tab @code{org-babel-tangle-file}
@item @kbd{C-c C-v c} or @kbd{C-c C-v C-c}
@tab @code{org-babel-check-src-block}
@item @kbd{C-c C-v j} or @kbd{C-c C-v C-j}
@tab @code{org-babel-insert-header-arg}
@item @kbd{C-c C-v l} or @kbd{C-c C-v C-l}
@tab @code{org-babel-load-in-session}
@item @kbd{C-c C-v i} or @kbd{C-c C-v C-i}
@tab @code{org-babel-lob-ingest}
@item @kbd{C-c C-v I} or @kbd{C-c C-v C-I}
@tab @code{org-babel-view-src-block-info}
@item @kbd{C-c C-v z} or @kbd{C-c C-v C-z}
@tab @code{org-babel-switch-to-session-with-code}
@item @kbd{C-c C-v a} or @kbd{C-c C-v C-a}
@tab @code{org-babel-sha1-hash}
@item @kbd{C-c C-v h} or @kbd{C-c C-v C-h}
@tab @code{org-babel-describe-bindings}
@item @kbd{C-c C-v x} or @kbd{C-c C-v C-x}
@tab @code{org-babel-do-key-sequence-in-edit-buffer}
@end multitable

@node Batch Execution
@section Batch Execution

@cindex code block, batch execution
@cindex source code, batch execution

Org mode features, including working with source code facilities can
be invoked from the command line.  This enables building shell scripts
for batch processing, running automated system tasks, and expanding
Org mode's usefulness.

The sample script shows batch processing of multiple files using
@code{org-babel-tangle}.

@example
#!/bin/sh
# Tangle files with Org mode
#
emacs -Q --batch --eval "
    (progn
      (require 'ob-tangle)
      (dolist (file command-line-args-left)
        (with-current-buffer (find-file-noselect file)
          (org-babel-tangle))))
  " "$@@"
@end example

@node Miscellaneous
@chapter Miscellaneous

@menu
* Completion::                   @kbd{M-@key{TAB}} guesses completions.
* Structure Templates::          Quick insertion of structural elements.
* Speed Keys::                   Electric commands at the beginning of a headline.
* Clean View::                   Getting rid of leading stars in the outline.
* Dynamic Headline Numbering::   Display and update outline numbering.
* The Very Busy @kbd{C-c C-c} Key:: When in doubt, press @kbd{C-c C-c}.
* In-buffer Settings::           Overview of keywords.
* Org Syntax::                   Formal description of Org's syntax.
* Documentation Access::         Read documentation about current syntax.
* Escape Character::
* Code Evaluation Security::     Org files evaluate in-line code.
* Interaction::                  With other Emacs packages.
* TTY Keys::                     Using Org on a tty.
* Protocols::                    External access to Emacs and Org.
* Org Crypt::                    Encrypting Org files.
* Org Mobile::                   Viewing and capture on a mobile device.
@end menu

@node Completion
@section Completion

@cindex completion, of @TeX{} symbols
@cindex completion, of TODO keywords
@cindex completion, of dictionary words
@cindex completion, of option keywords
@cindex completion, of tags
@cindex completion, of property keys
@cindex completion, of link abbreviations
@cindex @TeX{} symbol completion
@cindex TODO keywords completion
@cindex dictionary word completion
@cindex option keyword completion
@cindex tag completion
@cindex link abbreviations, completion of

Org has in-buffer completions.  Unlike minibuffer completions, which
are useful for quick command interactions, Org's in-buffer completions
are more suitable for content creation in Org documents.  Type one or
more letters and invoke the hot key to complete the text in-place.
Depending on the context and the keys, Org offers different types of
completions.  No minibuffer is involved.  Such mode-specific hot keys
have become an integral part of Emacs and Org provides several
shortcuts.

@table @asis
@item @kbd{M-@key{TAB}}
@kindex M-TAB

Complete word at point.

@itemize
@item
At the beginning of an empty headline, complete TODO keywords.

@item
After @samp{\}, complete @TeX{} symbols supported by the exporter.

@item
After @samp{*}, complete headlines in the current buffer so that they
can be used in search links like: @samp{[[*find this headline]]}

@item
After @samp{:} in a headline, complete tags.  Org deduces the list of
tags from the @samp{TAGS} in-buffer option (see @ref{Setting Tags}), the
variable @code{org-tag-alist}, or from all tags used in the current
buffer.

@item
After @samp{:} and not in a headline, complete property keys.  The list
of keys is constructed dynamically from all keys used in the
current buffer.

@item
After @samp{[}, complete link abbreviations (see @ref{Link Abbreviations}).

@item
After @samp{#+}, complete the special keywords like @samp{TYP_TODO} or
file-specific @samp{OPTIONS}.  After option keyword is complete,
pressing @kbd{M-@key{TAB}} again inserts example settings for this
keyword.

@item
After @samp{STARTUP} keyword, complete startup items.

@item
When point is anywhere else, complete dictionary words using
Ispell.
@end itemize
@end table

@node Structure Templates
@section Structure Templates

@cindex template insertion
@cindex insertion, of templates

With just a few keystrokes, it is possible to insert empty structural
blocks, such as @samp{#+BEGIN_SRC} @dots{} @samp{#+END_SRC}, or to wrap existing
text in such a block.

@table @asis
@item @kbd{C-c C-,} (@code{org-insert-structure-template})
@findex org-insert-structure-template
@kindex C-c C-,
Prompt for a type of block structure, and insert the block at point.
If the region is active, it is wrapped in the block.  First prompts
the user for keys, which are used to look up a structure type from
the variable below.  If the key is @kbd{@key{TAB}}, @kbd{@key{RET}},
or @kbd{@key{SPC}}, the user is prompted to enter a block type.
@end table

@vindex org-structure-template-alist
Available structure types are defined in
@code{org-structure-template-alist}, see the docstring for adding or
changing values.

@cindex Tempo
@cindex template expansion
@cindex insertion, of templates
@vindex org-tempo-keywords-alist
Org Tempo expands snippets to structures defined in
@code{org-structure-template-alist} and @code{org-tempo-keywords-alist}.  For
example, @kbd{< s @key{TAB}} creates a code block.  Enable it by
customizing @code{org-modules} or add @samp{(require 'org-tempo)} to your Emacs
init file@footnote{For more information, please refer to the commentary section
in @samp{org-tempo.el}.}.

@multitable @columnfractions 0.1 0.9
@item @kbd{a}
@tab @samp{#+BEGIN_EXPORT ascii} @dots{} @samp{#+END_EXPORT}
@item @kbd{c}
@tab @samp{#+BEGIN_CENTER} @dots{} @samp{#+END_CENTER}
@item @kbd{C}
@tab @samp{#+BEGIN_COMMENT} @dots{} @samp{#+END_COMMENT}
@item @kbd{e}
@tab @samp{#+BEGIN_EXAMPLE} @dots{} @samp{#+END_EXAMPLE}
@item @kbd{E}
@tab @samp{#+BEGIN_EXPORT} @dots{} @samp{#+END_EXPORT}
@item @kbd{h}
@tab @samp{#+BEGIN_EXPORT html} @dots{} @samp{#+END_EXPORT}
@item @kbd{l}
@tab @samp{#+BEGIN_EXPORT latex} @dots{} @samp{#+END_EXPORT}
@item @kbd{q}
@tab @samp{#+BEGIN_QUOTE} @dots{} @samp{#+END_QUOTE}
@item @kbd{s}
@tab @samp{#+BEGIN_SRC} @dots{} @samp{#+END_SRC}
@item @kbd{v}
@tab @samp{#+BEGIN_VERSE} @dots{} @samp{#+END_VERSE}
@end multitable

@node Speed Keys
@section Speed Keys

@cindex speed keys

Single keystrokes can execute custom commands in an Org file when
point is on a headline.  Without the extra burden of a meta or
modifier key, Speed Keys can speed navigation or execute custom
commands.  Besides faster navigation, Speed Keys may come in handy on
small mobile devices that do not have full keyboards.  Speed Keys may
also work on TTY devices known for their problems when entering Emacs
key chords.

@vindex org-use-speed-commands
By default, Org has Speed Keys disabled.  To activate Speed Keys, set
the variable @code{org-use-speed-commands} to a non-@code{nil} value.  To
trigger a Speed Key, point must be at the beginning of an Org
headline, before any of the stars.

@vindex org-speed-commands-user
@findex org-speed-command-help
Org comes with a pre-defined list of Speed Keys.  To add or modify
Speed Keys, customize the variable, @code{org-speed-commands-user}.  For
more details, see the variable's docstring.  With Speed Keys
activated, @kbd{M-x org-speed-command-help}, or @kbd{?} when
point is at the beginning of an Org headline, shows currently active
Speed Keys, including the user-defined ones.

@node Clean View
@section A Cleaner Outline View

@cindex hiding leading stars
@cindex dynamic indentation
@cindex odd-levels-only outlines
@cindex clean outline view

Org's outline with stars and no indents can look cluttered for short
documents.  For @emph{book-like} long documents, the effect is not as
noticeable.  Org provides an alternate stars and indentation scheme,
as shown on the right in the following table.  It displays only one
star and indents text to line up with the heading:

@example
* Top level headline             |    * Top level headline
** Second level                  |      * Second level
*** Third level                  |        * Third level
some text                        |          some text
*** Third level                  |        * Third level
more text                        |          more text
* Another top level headline     |    * Another top level headline
@end example

Org can achieve this in two ways, (1) by just displaying the buffer in
this way without changing it, or (2) by actually indenting every line
in the desired amount with hard spaces and hiding leading stars.

@menu
* Org Indent Mode::
* Hard indentation::
@end menu

@node Org Indent Mode
@subsection Org Indent Mode

@cindex Indent mode
@findex org-indent-mode
To display the buffer in the indented view, activate Org Indent minor
mode, using @kbd{M-x org-indent-mode}.  Text lines that are not
headlines are prefixed with virtual spaces to vertically align with
the headline text@footnote{Org Indent mode also sets @code{wrap-prefix} correctly for
indenting and wrapping long lines of headlines or text.  This minor
mode also handles Visual Line mode and directly applied settings
through @code{word-wrap}.}.

@vindex org-indent-indentation-per-level
To make more horizontal space, the headlines are shifted by two
characters.  Configure @code{org-indent-indentation-per-level} variable for
a different number.  Only one star on each headline is visible, the
rest are masked with the same font color as the background@footnote{Note that turning on Org Indent mode sets
@code{org-hide-leading-stars} to @code{t} and @code{org-adapt-indentation} to @code{nil}.}.

@vindex org-startup-indented
To globally turn on Org Indent mode for all files, customize the
variable @code{org-startup-indented}.  To control it for individual files,
use @samp{STARTUP} keyword as follows:

@example
#+STARTUP: indent
#+STARTUP: noindent
@end example

@node Hard indentation
@subsection Hard indentation

It is possible to use hard spaces to achieve the indentation instead,
if the bare ASCII file should have the indented look also outside
Emacs@footnote{This works, but requires extra effort.  Org Indent mode is
more convenient for most applications.}.  With Org's support, you have to indent all lines to
line up with the outline headers.  You would use these settings:

@lisp
(setq org-adapt-indentation t
      org-hide-leading-stars t
      org-odd-levels-only t)
@end lisp

@table @asis
@item @emph{Indentation of text below headlines} (@code{org-adapt-indentation})
@vindex org-adapt-indentation
The first setting modifies paragraph filling, line wrapping, and
structure editing commands to preserving or adapting the indentation
as appropriate.

@item @emph{Hiding leading stars} (@code{org-hide-leading-stars})
@vindex org-hide-leading-stars
@vindex org-hide, face
The second setting makes leading stars invisible by applying the
face @code{org-hide} to them.  For per-file preference, use these file
@samp{STARTUP} options:

@example
#+STARTUP: hidestars
#+STARTUP: showstars
@end example

@item @emph{Odd levels} (@code{org-odd-levels-only})
@vindex org-odd-levels-only
The third setting makes Org use only odd levels, 1, 3, 5, @dots{}, in
the outline to create more indentation.  On a  per-file level,
control this with:

@example
#+STARTUP: odd
#+STARTUP: oddeven
@end example

To convert a file between single and double stars layouts, use
@kbd{M-x org-convert-to-odd-levels} and @kbd{M-x org-convert-to-oddeven-levels}.
@end table

@node Dynamic Headline Numbering
@section Dynamic Headline Numbering

@cindex Org Num mode
@cindex number headlines
The Org Num minor mode, toggled with @kbd{M-x org-num-mode},
displays outline numbering on top of headlines.  It also updates it
automatically upon changes to the structure of the document.

@vindex org-num-max-level
@vindex org-num-skip-tags
@vindex org-num-skip-commented
@vindex org-num-skip-unnumbered
By default, all headlines are numbered.  You can limit numbering to
specific headlines according to their level, tags, @samp{COMMENT} keyword,
or @samp{UNNUMBERED} property.  Set @code{org-num-max-level},
@code{org-num-skip-tags}, @code{org-num-skip-commented},
@code{org-num-skip-unnumbered}, or @code{org-num-skip-footnotes} accordingly.

@vindex org-num-skip-footnotes
If @code{org-num-skip-footnotes} is non-@code{nil}, footnotes sections (see
@ref{Creating Footnotes}) are not numbered either.

@vindex org-num-face
@vindex org-num-format-function
You can control how the numbering is displayed by setting
@code{org-num-face} and @code{org-num-format-function}.

@node The Very Busy @kbd{C-c C-c} Key
@section The Very Busy @kbd{C-c C-c} Key

@kindex C-c C-c
@cindex @kbd{C-c C-c}, overview

The @kbd{C-c C-c} key in Org serves many purposes depending on
the context.  It is probably the most over-worked, multi-purpose key
combination in Org.  Its uses are well documented throughout this
manual, but here is a consolidated list for easy reference.

@itemize
@item
If any highlights shown in the buffer from the creation of a sparse
tree, or from clock display, remove such highlights.

@item
If point is in one of the special @samp{KEYWORD} lines, scan the buffer
for these lines and update the information.  Also reset the Org file
cache used to temporary store the contents of URLs used as values
for keywords like @samp{SETUPFILE}.

@item
If point is inside a table, realign the table.

@item
If point is on a @samp{TBLFM} keyword, re-apply the formulas to the
entire table.

@item
If the current buffer is a capture buffer, close the note and file
it.  With a prefix argument, also jump to the target location after
saving the note.

@item
If point is on a @samp{<<<target>>>}, update radio targets and
corresponding links in this buffer.

@item
If point is on a property line or at the start or end of a property
drawer, offer property commands.

@item
If point is at a footnote reference, go to the corresponding
definition, and @emph{vice versa}.

@item
If point is on a statistics cookie, update it.

@item
If point is in a plain list item with a checkbox, toggle the status
of the checkbox.

@item
If point is on a numbered item in a plain list, renumber the ordered
list.

@item
If point is on the @samp{#+BEGIN} line of a dynamic block, the block is
updated.

@item
If point is at a timestamp, fix the day name in the timestamp.
@end itemize

@node In-buffer Settings
@section Summary of In-Buffer Settings

@cindex in-buffer settings
@cindex special keywords

In-buffer settings start with @samp{#+}, followed by a keyword, a colon,
and then a word for each setting.  Org accepts multiple settings on
the same line.  Org also accepts multiple lines for a keyword.  This
manual describes these settings throughout.  A summary follows here.

@cindex refresh set-up
@kbd{C-c C-c} activates any changes to the in-buffer settings.
Closing and reopening the Org file in Emacs also activates the
changes.

@table @asis
@item @samp{#+ARCHIVE: %s_done}
@cindex @samp{ARCHIVE}, keyword
@vindex org-archive-location
Sets the archive location of the agenda file.  The corresponding
variable is @code{org-archive-location}.

@item @samp{#+CATEGORY}
@cindex @samp{CATEGORY}, keyword
Sets the category of the agenda file, which applies to the entire
document.

@item @samp{#+COLUMNS: %25ITEM ...}
@cindex @samp{COLUMNS}, property
Set the default format for columns view.  This format applies when
columns view is invoked in locations where no @samp{COLUMNS} property
applies.

@item @samp{#+CONSTANTS: name1=value1 ...}
@cindex @samp{CONSTANTS}, keyword
@vindex org-table-formula-constants
@vindex org-table-formula
Set file-local values for constants that table formulas can use.
This line sets the local variable
@code{org-table-formula-constants-local}.  The global version of this
variable is @code{org-table-formula-constants}.

@item @samp{#+FILETAGS: :tag1:tag2:tag3:}
@cindex @samp{FILETAGS}, keyword
Set tags that all entries in the file inherit from, including the
top-level entries.

@item @samp{#+LINK: linkword replace}
@cindex @samp{LINK}, keyword
@vindex org-link-abbrev-alist
Each line specifies one abbreviation for one link.  Use multiple
@samp{LINK} keywords for more, see @ref{Link Abbreviations}.  The
corresponding variable is @code{org-link-abbrev-alist}.

@item @samp{#+PRIORITIES: highest lowest default}
@cindex @samp{PRIORITIES}, keyword
@vindex org-highest-priority
@vindex org-lowest-priority
@vindex org-default-priority
This line sets the limits and the default for the priorities.  All
three must be either letters A--Z or numbers 0--9.  The highest
priority must have a lower ASCII number than the lowest priority.

@item @samp{#+PROPERTY: Property_Name Value}
@cindex @samp{PROPERTY}, keyword
This line sets a default inheritance value for entries in the
current buffer, most useful for specifying the allowed values of
a property.

@item @samp{#+SETUPFILE: file}
@cindex @samp{SETUPFILE}, keyword
The setup file or a URL pointing to such file is for additional
in-buffer settings.  Org loads this file and parses it for any
settings in it only when Org opens the main file.  If URL is
specified, the contents are downloaded and stored in a temporary
file cache.  @kbd{C-c C-c} on the settings line parses and
loads the file, and also resets the temporary file cache.  Org also
parses and loads the document during normal exporting process.  Org
parses the contents of this document as if it was included in the
buffer.  It can be another Org file.  To visit the file---not
a URL---use @kbd{C-c '} while point is on the line with the
file name.

@item @samp{#+STARTUP:}
@cindex @samp{STARTUP}, keyword
Startup options Org uses when first visiting a file.

@vindex org-startup-folded
The first set of options deals with the initial visibility of the
outline tree.  The corresponding variable for global default
settings is @code{org-startup-folded} with a default value of @code{t}, which
is the same as @code{overview}.

@multitable {aaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{overview}
@tab Top-level headlines only.
@item @samp{content}
@tab All headlines.
@item @samp{showall}
@tab No folding on any entry.
@item @samp{showeverything}
@tab Show even drawer contents.
@end multitable

@vindex org-startup-indented
Dynamic virtual indentation is controlled by the variable
@code{org-startup-indented}@footnote{Note that Org Indent mode also sets the @code{wrap-prefix}
property, such that Visual Line mode (or purely setting @code{word-wrap})
wraps long lines, including headlines, correctly indented.}.

@multitable {aaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{indent}
@tab Start with Org Indent mode turned on.
@item @samp{noindent}
@tab Start with Org Indent mode turned off.
@end multitable

@vindex org-startup-align-all-tables
Aligns tables consistently upon visiting a file.  The
corresponding variable is @code{org-startup-align-all-tables} with
@code{nil} as default value.

@multitable {aaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{align}
@tab Align all tables.
@item @samp{noalign}
@tab Do not align tables on startup.
@end multitable

@vindex org-startup-shrink-all-tables
Shrink table columns with a width cookie.  The corresponding
variable is @code{org-startup-shrink-all-tables} with @code{nil} as
default value.

@vindex org-startup-with-inline-images
When visiting a file, inline images can be automatically
displayed.  The corresponding variable is
@code{org-startup-with-inline-images}, with a default value @code{nil} to
avoid delays when visiting a file.

@multitable {aaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{inlineimages}
@tab Show inline images.
@item @samp{noinlineimages}
@tab Do not show inline images on startup.
@end multitable

@vindex org-log-done
@vindex org-log-note-clock-out
@vindex org-log-repeat
Logging the closing and reopening of TODO items and clock
intervals can be configured using these options (see variables
@code{org-log-done}, @code{org-log-note-clock-out}, and @code{org-log-repeat}).

@multitable {aaaaaaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{logdone}
@tab Record a timestamp when an item is marked as done.
@item @samp{lognotedone}
@tab Record timestamp and a note when DONE@.
@item @samp{nologdone}
@tab Do not record when items are marked as done.
@item @samp{logrepeat}
@tab Record a time when reinstating a repeating item.
@item @samp{lognoterepeat}
@tab Record a note when reinstating a repeating item.
@item @samp{nologrepeat}
@tab Do not record when reinstating repeating item.
@item @samp{lognoteclock-out}
@tab Record a note when clocking out.
@item @samp{nolognoteclock-out}
@tab Do not record a note when clocking out.
@item @samp{logreschedule}
@tab Record a timestamp when scheduling time changes.
@item @samp{lognotereschedule}
@tab Record a note when scheduling time changes.
@item @samp{nologreschedule}
@tab Do not record when a scheduling date changes.
@item @samp{logredeadline}
@tab Record a timestamp when deadline changes.
@item @samp{lognoteredeadline}
@tab Record a note when deadline changes.
@item @samp{nologredeadline}
@tab Do not record when a deadline date changes.
@item @samp{logrefile}
@tab Record a timestamp when refiling.
@item @samp{lognoterefile}
@tab Record a note when refiling.
@item @samp{nologrefile}
@tab Do not record when refiling.
@end multitable

@vindex org-hide-leading-stars
@vindex org-odd-levels-only
Here are the options for hiding leading stars in outline
headings, and for indenting outlines.  The corresponding
variables are @code{org-hide-leading-stars} and
@code{org-odd-levels-only}, both with a default setting @code{nil}
(meaning @samp{showstars} and @samp{oddeven}).

@multitable {aaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{hidestars}
@tab Make all but one of the stars starting a headline invisible.
@item @samp{showstars}
@tab Show all stars starting a headline.
@item @samp{indent}
@tab Virtual indentation according to outline level.
@item @samp{noindent}
@tab No virtual indentation according to outline level.
@item @samp{odd}
@tab Allow only odd outline levels (1, 3, @dots{}).
@item @samp{oddeven}
@tab Allow all outline levels.
@end multitable

@vindex org-put-time-stamp-overlays
@vindex org-time-stamp-overlay-formats
To turn on custom format overlays over timestamps (variables
@code{org-put-time-stamp-overlays} and
@code{org-time-stamp-overlay-formats}), use:

@multitable {aaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{customtime}
@tab Overlay custom time format.
@end multitable

@vindex constants-unit-system
The following options influence the table spreadsheet (variable
@code{constants-unit-system}).

@multitable {aaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{constcgs}
@tab @samp{constants.el} should use the c-g-s unit system.
@item @samp{constSI}
@tab @samp{constants.el} should use the SI unit system.
@end multitable

@vindex org-footnote-define-inline
@vindex org-footnote-auto-label
@vindex org-footnote-auto-adjust
To influence footnote settings, use the following keywords.  The
corresponding variables are @code{org-footnote-define-inline},
@code{org-footnote-auto-label}, and @code{org-footnote-auto-adjust}.

@multitable {aaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{fninline}
@tab Define footnotes inline.
@item @samp{fnnoinline}
@tab Define footnotes in separate section.
@item @samp{fnlocal}
@tab Define footnotes near first reference, but not inline.
@item @samp{fnprompt}
@tab Prompt for footnote labels.
@item @samp{fnauto}
@tab Create @samp{[fn:1]}-like labels automatically (default).
@item @samp{fnconfirm}
@tab Offer automatic label for editing or confirmation.
@item @samp{fnadjust}
@tab Automatically renumber and sort footnotes.
@item @samp{nofnadjust}
@tab Do not renumber and sort automatically.
@end multitable

@vindex org-hide-block-startup
To hide blocks on startup, use these keywords.  The
corresponding variable is @code{org-hide-block-startup}.

@multitable {aaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{hideblocks}
@tab Hide all begin/end blocks on startup.
@item @samp{nohideblocks}
@tab Do not hide blocks on startup.
@end multitable

@vindex org-pretty-entities
The display of entities as UTF-8 characters is governed by the
variable @code{org-pretty-entities} and the keywords

@multitable {aaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @samp{entitiespretty}
@tab Show entities as UTF-8 characters where possible.
@item @samp{entitiesplain}
@tab Leave entities plain.
@end multitable

@item @samp{#+TAGS: TAG1(c1) TAG2(c2)}
@cindex @samp{TAGS}, keyword
@vindex org-tag-alist
These lines (several such lines are allowed) specify the valid tags
in this file, and (potentially) the corresponding @emph{fast tag
selection} keys.  The corresponding variable is @code{org-tag-alist}.

@item @samp{#+TODO:}
@itemx @samp{#+SEQ_TODO:}
@itemx @samp{#+TYP_TODO:}
@cindex @samp{SEQ_TODO}, keyword
@cindex @samp{TODO}, keyword
@cindex @samp{TYP_TODO}, keyword
@vindex org-todo-keywords
These lines set the TODO keywords and their interpretation in the
current file.  The corresponding variable is @code{org-todo-keywords}.
@end table

@node Org Syntax
@section Org Syntax

A reference document providing a formal description of Org's syntax is
available as @uref{https://orgmode.org/worg/dev/org-syntax.html, a draft on Worg}, written and maintained by Nicolas
Goaziou.  It defines Org's core internal concepts such as ``headlines'',
``sections'', ``affiliated keywords'', ``(greater) elements'' and ``objects''.
Each part of an Org document belongs to one of the previous
categories.

To explore the abstract structure of an Org buffer, run this in
a buffer:

@example
M-: (org-element-parse-buffer) <RET>
@end example


@noindent
It outputs a list containing the buffer's content represented as an
abstract structure.  The export engine relies on the information
stored in this list.  Most interactive commands---e.g., for structure
editing---also rely on the syntactic meaning of the surrounding
context.

@cindex syntax checker
@cindex linter
@findex org-lint
You can probe the syntax of your documents with the command

@example
M-x org-lint <RET>
@end example


@noindent
It runs a number of checks to find common mistakes.  It then displays
their location in a dedicated buffer, along with a description and
a ``trust level'', since false-positive are possible.  From there, you
can operate on the reports with the following keys:

@multitable @columnfractions 0.22 0.78
@item @kbd{C-j}, @kbd{@key{TAB}}
@tab Display the offending line
@item @kbd{@key{RET}}
@tab Move point to the offending line
@item @kbd{g}
@tab Check the document again
@item @kbd{h}
@tab Hide all reports from the same checker
@item @kbd{i}
@tab Also remove them from all subsequent checks
@item @kbd{S}
@tab Sort reports by the column at point
@end multitable

@node Documentation Access
@section Context Dependent Documentation

@cindex documentation
@cindex Info

@findex org-info-find-node
@kindex C-c C-x I
@kbd{C-c C-x I} in an Org file tries to open a suitable section
of the Org manual depending on the syntax at point.  For example,
using it on a headline displays ``Document Structure'' section.

@kbd{q} closes the Info window.

@node Escape Character
@section Escape Character

@cindex escape character
@cindex zero width space
You may sometimes want to write text that looks like Org syntax, but
should really read as plain text.  Org may use a specific escape
character in some situations, e.g., a backslash in macros (see @ref{Macro Replacement}) or a comma in source and example blocks (see @ref{Literal Examples}).  In the general case, however, we suggest to use the zero
width space.  You can insert one with any of the following:

@example
C-x 8 <RET> zero width space <RET>
C-x 8 <RET> 200B <RET>
@end example


For example, in order to write @samp{[[1,2]]} as-is in your document, you
may write instead

@example
[X[1,2]]
@end example


where @samp{X} denotes the zero width space character.

@node Code Evaluation Security
@section Code Evaluation and Security Issues

Unlike plain text, running code comes with risk.  Each source code
block, in terms of risk, is equivalent to an executable file.  Org
therefore puts a few confirmation prompts by default.  This is to
alert the casual user from accidentally running untrusted code.

For users who do not run code blocks or write code regularly, Org's
default settings should suffice.  However, some users may want to
tweak the prompts for fewer interruptions.  To weigh the risks of
automatic execution of code blocks, here are some details about code
evaluation.

Org evaluates code in the following circumstances:

@table @asis
@item @emph{Source code blocks}
Org evaluates source code blocks in an Org file during export.  Org
also evaluates a source code block with the @kbd{C-c C-c} key
chord.  Users exporting or running code blocks must load files only
from trusted sources.  Be wary of customizing variables that remove
or alter default security measures.

@defopt org-confirm-babel-evaluate
When @code{t}, Org prompts the user for confirmation before executing
each code block.  When @code{nil}, Org executes code blocks without
prompting the user for confirmation.  When this option is set to
a custom function, Org invokes the function with these two
arguments: the source code language and the body of the code block.
The custom function must return either a @code{t} or @code{nil}, which
determines if the user is prompted.  Each source code language can
be handled separately through this function argument.
@end defopt

For example, here is how to execute ditaa code blocks without
prompting:

@lisp
(defun my-org-confirm-babel-evaluate (lang body)
  (not (string= lang "ditaa")))  ;don't ask for ditaa
(setq org-confirm-babel-evaluate #'my-org-confirm-babel-evaluate)
@end lisp

@item @emph{Following @samp{shell} and @samp{elisp} links}
Org has two link types that can directly evaluate code (see
@ref{External Links}).  Because such code is not visible, these links
have a potential risk.  Org therefore prompts the user when it
encounters such links.  The customization variables are:

@defopt org-link-shell-confirm-function
Function that prompts the user before executing a shell link.
@end defopt

@defopt org-link-elisp-confirm-function
Function that prompts the user before executing an Emacs Lisp link.
@end defopt

@item @emph{Formulas in tables}
Formulas in tables (see @ref{The Spreadsheet}) are code that is evaluated
either by the Calc interpreter, or by the Emacs Lisp interpreter.
@end table

@node Interaction
@section Interaction with Other Packages

@cindex packages, interaction with other

Org's compatibility and the level of interaction with other Emacs
packages are documented here.

@menu
* Cooperation::                  Packages Org cooperates with.
* Conflicts::                    Packages that lead to conflicts.
@end menu

@node Cooperation
@subsection Packages that Org cooperates with

@table @asis
@item @samp{calc.el} by Dave Gillespie
@cindex @file{calc.el}

Org uses the Calc package for implementing spreadsheet functionality
in its tables (see @ref{The Spreadsheet}).  Org also uses Calc for
embedded calculations.  See @ref{Embedded Mode,GNU Emacs Calc Manual,,calc,}.

@item @samp{constants.el} by Carsten Dominik
@cindex @file{constants.el}
@vindex org-table-formula-constants

Org can use names for constants in formulas in tables.  Org can also
use calculation suffixes for units, such as @samp{M} for @samp{Mega}.  For
a standard collection of such constants, install the @samp{constants}
package.  Install version 2.0 of this package, available at
@uref{http://www.astro.uva.nl/~dominik/Tools}.  Org checks if the function
@code{constants-get} has been autoloaded.  Installation instructions are
in the file @samp{constants.el}.

@item @samp{cdlatex.el} by Carsten Dominik
@cindex @file{cdlatex.el}

Org mode can make use of the CD@LaTeX{} package to efficiently enter
@LaTeX{} fragments into Org files.  See @ref{CD@LaTeX{} mode}.

@item @samp{imenu.el} by Ake Stenhoff and Lars Lindberg
@cindex @file{imenu.el}

Imenu creates dynamic menus based on an index of items in a file.
Org mode supports Imenu menus.  Enable it with a mode hook as
follows:

@lisp
(add-hook 'org-mode-hook
          (lambda () (imenu-add-to-menubar "Imenu")))
@end lisp

@vindex org-imenu-depth
By default the index is two levels deep---you can modify the
depth using the option @code{org-imenu-depth}.

@item @samp{speedbar.el} by Eric@tie{}M@.@tie{}Ludlam
@cindex @file{speedbar.el}

Speedbar package creates a special Emacs frame for displaying files
and index items in files.  Org mode supports Speedbar; users can
drill into Org files directly from the Speedbar.  The @kbd{<}
in the Speedbar frame tweaks the agenda commands to that file or to
a subtree.

@item @samp{table.el} by Takaaki Ota
@cindex table editor, @file{table.el}
@cindex @file{table.el}

Complex ASCII tables with automatic line wrapping, column- and
row-spanning, and alignment can be created using the Emacs table
package by Takaaki Ota.  Org mode recognizes such tables and exports
them properly.  @kbd{C-c '} to edit these tables in a special
buffer, much like Org's code blocks.  Because of interference with
other Org mode functionality, Takaaki Ota tables cannot be edited
directly in the Org buffer.

@table @asis
@item @kbd{C-c '} (@code{org-edit-special})
@kindex C-c '
@findex org-edit-special
Edit a @samp{table.el} table.  Works when point is in a @samp{table.el}
table.

@item @kbd{C-c ~​} (@code{org-table-create-with-table.el})
@kindex C-c ~
@findex org-table-create-with-table.el
Insert a @samp{table.el} table.  If there is already a table at point,
this command converts it between the @samp{table.el} format and the Org
mode format.  See the documentation string of the command
@code{org-convert-table} for the restrictions under which this is
possible.
@end table
@end table

@node Conflicts
@subsection Packages that conflict with Org mode

@cindex shift-selection
@vindex org-support-shift-select
In Emacs, shift-selection combines motions of point with shift key to
enlarge regions.  Emacs sets this mode by default.  This conflicts
with Org's use of @kbd{S-<cursor>} commands to change timestamps,
TODO keywords, priorities, and item bullet types, etc.  Since
@kbd{S-<cursor>} commands outside of specific contexts do not do
anything, Org offers the variable @code{org-support-shift-select} for
customization.  Org mode accommodates shift selection by (i) making it
available outside of the special contexts where special commands
apply, and (ii) extending an existing active region even if point
moves across a special context.

@table @asis
@item @samp{cua.el} by Kim@tie{}F@.@tie{}Storm
@cindex @file{cua.el}
@vindex org-replace-disputed-keys
Org key bindings conflict with @kbd{S-<cursor>} keys used by
CUA mode.  For Org to relinquish these bindings to CUA mode,
configure the variable @code{org-replace-disputed-keys}.  When set, Org
moves the following key bindings in Org files, and in the agenda
buffer---but not during date selection.

@multitable @columnfractions 0.4 0.4
@item @kbd{S-@key{UP}}      @result{}  @kbd{M-p}
@tab @kbd{S-@key{DOWN}}     @result{}  @kbd{M-n}
@item @kbd{S-@key{LEFT}}    @result{}  @kbd{M--}
@tab @kbd{S-@key{RIGHT}}    @result{}  @kbd{M-+}
@item @kbd{C-S-@key{LEFT}}  @result{}  @kbd{M-S--}
@tab @kbd{C-S-@key{RIGHT}}  @result{}  @kbd{M-S-+}
@end multitable

@vindex org-disputed-keys
Yes, these are unfortunately more difficult to remember.  If you
want to have other replacement keys, look at the variable
@code{org-disputed-keys}.

@item @samp{ecomplete.el} by Lars Magne Ingebrigtsen
@cindex @file{ecomplete.el}
Ecomplete provides ``electric'' address completion in address header
lines in message buffers.  Sadly Orgtbl mode cuts Ecomplete's power
supply: no completion happens when Orgtbl mode is enabled in message
buffers while entering text in address header lines.  If one wants
to use ecomplete one should @emph{not} follow the advice to automagically
turn on Orgtbl mode in message buffers (see @ref{Orgtbl Mode}),
but instead---after filling in the message headers---turn on Orgtbl
mode manually when needed in the messages body.

@item @samp{filladapt.el} by Kyle Jones
@cindex @file{filladapt.el}
Org mode tries to do the right thing when filling paragraphs, list
items and other elements.  Many users reported problems using both
@samp{filladapt.el} and Org mode, so a safe thing to do is to disable
filladapt like this:

@lisp
(add-hook 'org-mode-hook 'turn-off-filladapt-mode)
@end lisp

@item @samp{viper.el} by Michael Kifer
@cindex @file{viper.el}
@kindex C-c /

Viper uses @kbd{C-c /} and therefore makes this key not access
the corresponding Org mode command @code{org-sparse-tree}.  You need to
find another key for this command, or override the key in
@code{viper-vi-global-user-map} with

@lisp
(define-key viper-vi-global-user-map "C-c /" 'org-sparse-tree)
@end lisp

@item @samp{windmove.el} by Hovav Shacham
@cindex @file{windmove.el}

This package also uses the @kbd{S-<cursor>} keys, so everything
written in the paragraph above about CUA mode also applies here.  If
you want to make the windmove function active in locations where Org
mode does not have special functionality on @kbd{S-<cursor>},
add this to your configuration:

@lisp
;; Make windmove work in Org mode:
(add-hook 'org-shiftup-final-hook 'windmove-up)
(add-hook 'org-shiftleft-final-hook 'windmove-left)
(add-hook 'org-shiftdown-final-hook 'windmove-down)
(add-hook 'org-shiftright-final-hook 'windmove-right)
@end lisp

@item @samp{yasnippet.el}
@cindex @file{yasnippet.el}
The way Org mode binds the @kbd{@key{TAB}} key (binding to @code{[tab]}
instead of @code{"\t"}) overrules YASnippet's access to this key.  The
following code fixed this problem:

@lisp
(add-hook 'org-mode-hook
          (lambda ()
            (setq-local yas/trigger-key [tab])
            (define-key yas/keymap [tab] 'yas/next-field-or-maybe-expand)))
@end lisp

The latest version of YASnippet does not play well with Org mode.
If the above code does not fix the conflict, start by defining
the following function:

@lisp
(defun yas/org-very-safe-expand ()
  (let ((yas/fallback-behavior 'return-nil)) (yas/expand)))
@end lisp

Then, tell Org mode to use that function:

@lisp
(add-hook 'org-mode-hook
          (lambda ()
            (make-variable-buffer-local 'yas/trigger-key)
            (setq yas/trigger-key [tab])
            (add-to-list 'org-tab-first-hook 'yas/org-very-safe-expand)
            (define-key yas/keymap [tab] 'yas/next-field)))
@end lisp
@end table

@node TTY Keys
@section Using Org on a TTY

@cindex tty key bindings

Org provides alternative key bindings for TTY and modern mobile
devices that cannot perform movement commands on point and key
bindings with modifier keys.  Some of these workarounds may be more
cumbersome than necessary.  Users should look into customizing these
further based on their usage needs.  For example, the normal
@kbd{S-<cursor>} for editing timestamp might be better with
@kbd{C-c .} chord.

@multitable @columnfractions 0.2 0.28 0.15 0.21
@headitem Default
@tab Alternative 1
@tab Speed key
@tab Alternative 2
@item @kbd{S-@key{TAB}}
@tab @kbd{C-u @key{TAB}}
@tab @kbd{C}
@tab 
@item @kbd{M-@key{LEFT}}
@tab @kbd{C-c C-x l}
@tab @kbd{l}
@tab @kbd{Esc @key{LEFT}}
@item @kbd{M-S-@key{LEFT}}
@tab @kbd{C-c C-x L}
@tab @kbd{L}
@tab 
@item @kbd{M-@key{RIGHT}}
@tab @kbd{C-c C-x r}
@tab @kbd{r}
@tab @kbd{Esc @key{RIGHT}}
@item @kbd{M-S-@key{RIGHT}}
@tab @kbd{C-c C-x R}
@tab @kbd{R}
@tab 
@item @kbd{M-@key{UP}}
@tab @kbd{C-c C-x u}
@tab 
@tab @kbd{Esc @key{UP}}
@item @kbd{M-S-@key{UP}}
@tab @kbd{C-c C-x U}
@tab @kbd{U}
@tab 
@item @kbd{M-@key{DOWN}}
@tab @kbd{C-c C-x d}
@tab 
@tab @kbd{Esc @key{DOWN}}
@item @kbd{M-S-@key{DOWN}}
@tab @kbd{C-c C-x D}
@tab @kbd{D}
@tab 
@item @kbd{S-@key{RET}}
@tab @kbd{C-c C-x c}
@tab 
@tab 
@item @kbd{M-@key{RET}}
@tab @kbd{C-c C-x m}
@tab 
@tab @kbd{Esc @key{RET}}
@item @kbd{M-S-@key{RET}}
@tab @kbd{C-c C-x M}
@tab 
@tab 
@item @kbd{S-@key{LEFT}}
@tab @kbd{C-c @key{LEFT}}
@tab 
@tab 
@item @kbd{S-@key{RIGHT}}
@tab @kbd{C-c @key{RIGHT}}
@tab 
@tab 
@item @kbd{S-@key{UP}}
@tab @kbd{C-c @key{UP}}
@tab 
@tab 
@item @kbd{S-@key{DOWN}}
@tab @kbd{C-c @key{DOWN}}
@tab 
@tab 
@item @kbd{C-S-@key{LEFT}}
@tab @kbd{C-c C-x @key{LEFT}}
@tab 
@tab 
@item @kbd{C-S-@key{RIGHT}}
@tab @kbd{C-c C-x @key{RIGHT}}
@tab 
@tab 
@end multitable

@node Protocols
@section Protocols for External Access

@cindex protocols, for external access

Org protocol is a tool to trigger custom actions in Emacs from
external applications.  Any application that supports calling external
programs with an URL as argument may be used with this functionality.
For example, you can configure bookmarks in your web browser to send a
link to the current page to Org and create a note from it using
capture (see @ref{Capture}).  You can also create a bookmark that tells
Emacs to open the local source file of a remote website you are
browsing.

@cindex Org protocol, set-up
@cindex Installing Org protocol
In order to use Org protocol from an application, you need to register
@samp{org-protocol://} as a valid scheme-handler.  External calls are
passed to Emacs through the @samp{emacsclient} command, so you also need to
ensure an Emacs server is running.  More precisely, when the
application calls

@example
emacsclient org-protocol://PROTOCOL?key1=val1&key2=val2
@end example


@noindent
Emacs calls the handler associated to @var{PROTOCOL} with
argument @samp{(:key1 val1 :key2 val2)}.

@cindex protocol, new protocol
@cindex defining new protocols
Org protocol comes with three predefined protocols, detailed in the
following sections.  Configure @code{org-protocol-protocol-alist} to define
your own.

@menu
* The @code{store-link} protocol:: Store a link, push URL to kill-ring.
* The @code{capture} protocol::  Fill a buffer with external information.
* The @code{open-source} protocol:: Edit published contents.
@end menu

@node The @code{store-link} protocol
@subsection The @code{store-link} protocol

@cindex store-link protocol
@cindex protocol, store-link

Using the @code{store-link} handler, you can copy links, to that they can
be inserted using @kbd{M-x org-insert-link} or yanking.  More
precisely, the command

@example
emacsclient org-protocol://store-link?url=URL&title=TITLE
@end example


@noindent
stores the following link:

@example
[[URL][TITLE]]
@end example


In addition, @var{URL} is pushed on the kill-ring for yanking.
You need to encode @var{URL} and @var{TITLE} if they contain
slashes, and probably quote those for the shell.

To use this feature from a browser, add a bookmark with an arbitrary
name, e.g., @samp{Org: store-link} and enter this as @emph{Location}:

@example
javascript:location.href='org-protocol://store-link?url='+
      encodeURIComponent(location.href);
@end example

@node The @code{capture} protocol
@subsection The @code{capture} protocol

@cindex capture protocol
@cindex protocol, capture

Activating the ``capture'' handler pops up a @samp{Capture} buffer in Emacs,
using acapture template.

@example
emacsclient org-protocol://capture?template=X?url=URL?title=TITLE?body=BODY
@end example


To use this feature, add a bookmark with an arbitrary name, e.g.,
@samp{Org: capture}, and enter this as @samp{Location}:

@example
javascript:location.href='org-protocol://capture?template=x'+
      '&url='+encodeURIComponent(window.location.href)+
      '&title='+encodeURIComponent(document.title)+
      '&body='+encodeURIComponent(window.getSelection());
@end example

@vindex org-protocol-default-template-key
The capture template to be used can be specified in the bookmark (like
@samp{X} above). If unspecified, the template key is set in the variable
@code{org-protocol-default-template-key}. The following template
placeholders are available:

@example
%:link          The URL
%:description   The webpage title
%:annotation    Equivalent to [[%:link][%:description]]
%i              The selected text
@end example

@node The @code{open-source} protocol
@subsection The @code{open-source} protocol

@cindex open-source protocol
@cindex protocol, open-source

The @code{open-source} handler is designed to help with editing local
sources when reading a document.  To that effect, you can use
a bookmark with the following location:

@example
javascript:location.href='org-protocol://open-source?&url='+
      encodeURIComponent(location.href)
@end example

@vindex org-protocol-project-alist
The variable @code{org-protocol-project-alist} maps URLs to local file
names, by stripping URL parameters from the end and replacing the
@code{:base-url} with @code{:working-directory} and @code{:online-suffix} with
@code{:working-suffix}.  For example, assuming you own a local copy of
@samp{https://orgmode.org/worg/} contents at @samp{/home/user/worg}, you can set
@code{org-protocol-project-alist} to the following

@lisp
(setq org-protocol-project-alist
      '(("Worg"
         :base-url "https://orgmode.org/worg/"
         :working-directory "/home/user/worg/"
         :online-suffix ".html"
         :working-suffix ".org")))
@end lisp

@noindent
If you are now browsing
@samp{https://orgmode.org/worg/org-contrib/org-protocol.html} and find
a typo or have an idea about how to enhance the documentation, simply
click the bookmark and start editing.

@cindex rewritten URL in open-source protocol
@cindex protocol, open-source rewritten URL
However, such mapping may not always yield the desired results.
Suppose you maintain an online store located at @samp{http://example.com/}.
The local sources reside in @samp{/home/user/example/}.  It is common
practice to serve all products in such a store through one file and
rewrite URLs that do not match an existing file on the server.  That
way, a request to @samp{http://example.com/print/posters.html} might be
rewritten on the server to something like
@samp{http://example.com/shop/products.php/posters.html.php}.  The
@code{open-source} handler probably cannot find a file named
@samp{/home/user/example/print/posters.html.php} and fails.

Such an entry in @code{org-protocol-project-alist} may hold an additional
property @code{:rewrites}.  This property is a list of cons cells, each of
which maps a regular expression to a path relative to the
@code{:working-directory}.

Now map the URL to the path @samp{/home/user/example/products.php} by
adding @code{:rewrites} rules like this:

@lisp
(setq org-protocol-project-alist
      '(("example.com"
         :base-url "http://example.com/"
         :working-directory "/home/user/example/"
         :online-suffix ".php"
         :working-suffix ".php"
         :rewrites (("example.com/print/" . "products.php")
                    ("example.com/$" . "index.php")))))
@end lisp

@noindent
Since @samp{example.com/$} is used as a regular expression, it maps
@samp{http://example.com/}, @samp{https://example.com},
@samp{http://www.example.com/} and similar to
@samp{/home/user/example/index.php}.

The @code{:rewrites} rules are searched as a last resort if and only if no
existing file name is matched.

@cindex protocol, open-source, set-up mapping
@cindex mappings in open-source protocol
@findex org-protocol-create
@findex org-protocol-create-for-org
Two functions can help you filling @code{org-protocol-project-alist} with
valid contents: @code{org-protocol-create} and
@code{org-protocol-create-for-org}.  The latter is of use if you're editing
an Org file that is part of a publishing project.

@node Org Crypt
@section Org Crypt

Org Crypt encrypts the text of an entry, but not the headline, or
properties.  Behind the scene, it uses the Emacs EasyPG library to
encrypt and decrypt files.

@vindex org-crypt-tag-matcher
Any text below a headline that has a @samp{crypt} tag is automatically
encrypted when the file is saved.  To use a different tag, customize
the @code{org-crypt-tag-matcher} setting.

Here is a suggestion for Org Crypt settings in Emacs init file:

@lisp
(require 'org-crypt)
(org-crypt-use-before-save-magic)
(setq org-tags-exclude-from-inheritance '("crypt"))

(setq org-crypt-key nil)
;; GPG key to use for encryption
;; Either the Key ID or set to nil to use symmetric encryption.

(setq auto-save-default nil)
;; Auto-saving does not cooperate with org-crypt.el: so you need to
;; turn it off if you plan to use org-crypt.el quite often.  Otherwise,
;; you'll get an (annoying) message each time you start Org.

;; To turn it off only locally, you can insert this:
;;
;; # -*- buffer-auto-save-file-name: nil; -*-
@end lisp

It's possible to use different keys for different headings by
specifying the respective key as property @samp{CRYPTKEY}, e.g.:

@example
* Totally secret :crypt:
  :PROPERTIES:
  :CRYPTKEY: 0x0123456789012345678901234567890123456789
  :END:
@end example

Excluding the @samp{crypt} tag from inheritance prevents already encrypted
text from being encrypted again.

@node Org Mobile
@section Org Mobile

@cindex smartphone

Org Mobile is a protocol for synchronizing Org files between Emacs and
other applications, e.g., on mobile devices.  It enables offline-views
and capture support for an Org mode system that is rooted on a ``real''
computer.  The external application can also record changes to
existing entries.

This appendix describes Org's support for agenda view formats
compatible with Org Mobile.  It also describes synchronizing changes,
such as to notes, between the mobile application and the computer.

To change tags and TODO states in the mobile application, first
customize the variables @code{org-todo-keywords} and @code{org-tag-alist}.
These should cover all the important tags and TODO keywords, even if
Org files use only some of them.  Though the mobile application is
expected to support in-buffer settings, it is required to understand
TODO states @emph{sets} (see @ref{Per-file keywords}) and
@emph{mutually exclusive} tags (see @ref{Setting Tags}) only for those set in
these variables.

@menu
* Setting up the staging area::  For the mobile device.
* Pushing to the mobile application:: Uploading Org files and agendas.
* Pulling from the mobile application:: Integrating captured and flagged items.
@end menu

@node Setting up the staging area
@subsection Setting up the staging area

@vindex org-mobile-directory
The mobile application needs access to a file directory on
a server@footnote{For a server to host files, consider using a WebDAV server,
such as @uref{https://nextcloud.com, Nextcloud}.  Additional help is at this @uref{https://orgmode.org/worg/org-faq.html#mobileorg_webdav, FAQ entry}.} to interact with Emacs.  Pass its location through
the @code{org-mobile-directory} variable.  If you can mount that directory
locally just set the variable to point to that directory:

@lisp
(setq org-mobile-directory "~/orgmobile/")
@end lisp

Alternatively, by using TRAMP (see @ref{Top,TRAMP User Manual,,tramp,}),
@code{org-mobile-directory} may point to a remote directory accessible
through, for example, SSH, SCP, or DAVS:

@lisp
(setq org-mobile-directory "/davs:user@@remote.host:/org/webdav/")
@end lisp

@vindex org-mobile-encryption
With a public server, consider encrypting the files.  Org also
requires OpenSSL installed on the local computer.  To turn on
encryption, set the same password in the mobile application and in
Emacs.  Set the password in the variable
@code{org-mobile-use-encryption}@footnote{If Emacs is configured for safe storing of passwords, then
configure the variable @code{org-mobile-encryption-password}; please read
the docstring of that variable.}.  Note that even after the mobile
application encrypts the file contents, the file name remains visible
on the file systems of the local computer, the server, and the mobile
device.

@node Pushing to the mobile application
@subsection Pushing to the mobile application

@findex org-mobile-push
@vindex org-mobile-files
The command @code{org-mobile-push} copies files listed in
@code{org-mobile-files} into the staging area.  Files include agenda files
(as listed in @code{org-agenda-files}).  Customize @code{org-mobile-files} to
add other files.  File names are staged with paths relative to
@code{org-directory}, so all files should be inside this directory@footnote{Symbolic links in @code{org-directory} need to have the same name
as their targets.}.

Push creates a special Org file @samp{agendas.org} with custom agenda views
defined by the user@footnote{While creating the agendas, Org mode forces @samp{ID} properties
on all referenced entries, so that these entries can be uniquely
identified if Org Mobile flags them for further action.  To avoid
setting properties configure the variable
@code{org-mobile-force-id-on-agenda-items} to @code{nil}.  Org mode then relies
on outline paths, assuming they are unique.}.

Finally, Org writes the file @samp{index.org}, containing links to other
files.  The mobile application reads this file first from the server
to determine what other files to download for agendas.  For faster
downloads, it is expected to only read files whose checksums@footnote{Checksums are stored automatically in the file
@samp{checksums.dat}.}
have changed.

@node Pulling from the mobile application
@subsection Pulling from the mobile application

@findex org-mobile-pull
The command @code{org-mobile-pull} synchronizes changes with the server.
More specifically, it first pulls the Org files for viewing.  It then
appends captured entries and pointers to flagged or changed entries to
the file @samp{mobileorg.org} on the server.  Org ultimately integrates its
data in an inbox file format, through the following steps:

@enumerate
@item
@vindex org-mobile-inbox-for-pull
Org moves all entries found in @samp{mobileorg.org}@footnote{The file will be empty after this operation.} and appends
them to the file pointed to by the variable
@code{org-mobile-inbox-for-pull}.  It should reside neither in the
staging area nor on the server.  Each captured entry and each
editing event is a top-level entry in the inbox file.

@item
@cindex @samp{FLAGGED}, tag
After moving the entries, Org processes changes to the shared
files.  Some of them are applied directly and without user
interaction.  Examples include changes to tags, TODO state,
headline and body text.  Entries requiring further action are
tagged as @samp{FLAGGED}.  Org marks entries with problems with an error
message in the inbox.  They have to be resolved manually.

@item
Org generates an agenda view for flagged entries for user
intervention to clean up.  For notes stored in flagged entries, Org
displays them in the echo area when point is on the corresponding
agenda item.

@table @asis
@item @kbd{?}
Pressing @kbd{?} displays the entire flagged note in another
window.  Org also pushes it to the kill ring.  To store flagged
note as a normal note, use @kbd{? z C-y C-c C-c}.  Pressing
@kbd{?} twice does these things: first it removes the
@samp{FLAGGED} tag; second, it removes the flagged note from the
property drawer; third, it signals that manual editing of the
flagged entry is now finished.
@end table
@end enumerate

@kindex ? @r{(Agenda dispatcher)}
From the agenda dispatcher, @kbd{?} returns to the view to finish
processing flagged entries.  Note that these entries may not be the
most recent since the mobile application searches files that were last
pulled.  To get an updated agenda view with changes since the last
pull, pull again.

@node Hacking
@appendix Hacking

@cindex hacking

This appendix describes some ways a user can extend the functionality
of Org.

@menu
* Hooks: Hooks (2).              How to reach into Org's internals.
* Add-on Packages::              Available extensions.
* Adding Hyperlink Types::       New custom link types.
* Adding Export Back-ends::      How to write new export back-ends.
* Tables in Arbitrary Syntax::   Orgtbl for LaTeX and other programs.
* Dynamic Blocks::               Automatically filled blocks.
* Special Agenda Views::         Customized views.
* Speeding Up Your Agendas::     Tips on how to speed up your agendas.
* Extracting Agenda Information:: Post-processing agenda information.
* Using the Property API::       Writing programs that use entry properties.
* Using the Mapping API::        Mapping over all or selected entries.
@end menu

@node Hooks (2)
@appendixsec Hooks

@cindex hooks

Org has a large number of hook variables for adding functionality.
This appendix illustrates using a few.  A complete list of hooks with
documentation is maintained by the Worg project at
@uref{https://orgmode.org/worg/doc.html#hooks}.

@node Add-on Packages
@appendixsec Add-on Packages

@cindex add-on packages

Various authors wrote a large number of add-on packages for Org.

These packages are not part of Emacs, but they are distributed as
contributed packages with the separate release available at
@uref{https://orgmode.org}.  See the @samp{contrib/README} file in the source code
directory for a list of contributed files.  Worg page with more
information is at: @uref{https://orgmode.org/worg/org-contrib/}.

@node Adding Hyperlink Types
@appendixsec Adding Hyperlink Types

@cindex hyperlinks, adding new types

Org has many built-in hyperlink types (see @ref{Hyperlinks}), and an
interface for adding new link types.  The following example shows the
process of adding Org links to Unix man pages, which look like this

@example
[[man:printf][The printf manual]]
@end example


@noindent
The following @samp{org-man.el} file implements it

@lisp
;;; org-man.el - Support for links to man pages in Org mode
(require 'org)

(org-link-set-parameters "man"
                         :follow org-man-command
                         :export #'org-man-export
                         :store #'org-man-store-link)

(defcustom org-man-command 'man
  "The Emacs command to be used to display a man page."
  :group 'org-link
  :type '(choice (const man) (const woman)))

(defun org-man-store-link ()
  "Store a link to a man page."
  (when (memq major-mode '(Man-mode woman-mode))
    ;; This is a man page, we do make this link.
    (let* ((page (org-man-get-page-name))
           (link (concat "man:" page))
           (description (format "Man page for %s" page)))
      (org-store-link-props
       :type "man"
       :link link
       :description description))))

(defun org-man-get-page-name ()
  "Extract the page name from the buffer name."
  ;; This works for both `Man-mode' and `woman-mode'.
  (if (string-match " \\(\\S-+\\)\\*" (buffer-name))
      (match-string 1 (buffer-name))
    (error "Cannot create link to this man page")))

(defun org-man-export (link description format)
  "Export a man page link from Org files."
  (let ((path (format "http://man.he.net/?topic=%s&section=all" link))
        (desc (or description link)))
    (pcase format
      (`html (format "<a target=\"_blank\" href=\"%s\">%s</a>" path desc))
      (`latex (format "\\href@{%s@}@{%s@}" path desc))
      (`texinfo (format "@@uref@{%s,%s@}" path desc))
      (`ascii (format "%s (%s)" desc path))
      (t path))))

(provide 'org-man)
;;; org-man.el ends here
@end lisp

@noindent
To activate links to man pages in Org, enter this in the Emacs init
file:

@lisp
(require 'org-man)
@end lisp

@noindent
A review of @samp{org-man.el}:

@enumerate
@item
First, @samp{(require 'org)} ensures @samp{org.el} is loaded.

@item
@findex org-link-set-parameters
@vindex org-link-parameters
Then @code{org-link-set-parameters} defines a new link type with @samp{man}
prefix and associates functions for following, exporting and
storing such links.  See the variable @code{org-link-parameters} for
a complete list of possible associations.

@item
The rest of the file implements necessary variables and functions.

For example, @code{org-man-store-link} is responsible for storing a link
when @code{org-store-link} (see @ref{Handling Links}) is called from a buffer
displaying a man page.  It first checks if the major mode is
appropriate.  If check fails, the function returns @code{nil}, which
means it isn't responsible for creating a link to the current
buffer.  Otherwise the function makes a link string by combining
the @samp{man:} prefix with the man topic.  It also provides a default
description.  The function @code{org-insert-link} can insert it back
into an Org buffer later on.
@end enumerate

@node Adding Export Back-ends
@appendixsec Adding Export Back-ends

@cindex Export, writing back-ends

Org's export engine makes it easy for writing new back-ends.  The
framework on which the engine was built makes it easy to derive new
back-ends from existing ones.

@findex org-export-define-backend
@findex org-export-define-derived-backend
The two main entry points to the export engine are:
@code{org-export-define-backend} and @code{org-export-define-derived-backend}.
To grok these functions, see @samp{ox-latex.el} for an example of defining
a new back-end from scratch, and @samp{ox-beamer.el} for an example of
deriving from an existing engine.

For creating a new back-end from scratch, first set its name as
a symbol in an alist consisting of elements and export functions.  To
make the back-end visible to the export dispatcher, set @code{:menu-entry}
keyword.  For export options specific to this back-end, set the
@code{:options-alist}.

For creating a new back-end from an existing one, set
@code{:translate-alist} to an alist of export functions.  This alist
replaces the parent back-end functions.

For complete documentation, see @uref{https://orgmode.org/worg/dev/org-export-reference.html, the Org Export Reference on Worg}.

@node Tables in Arbitrary Syntax
@appendixsec Tables in Arbitrary Syntax

@cindex tables, in other modes
@cindex lists, in other modes
@cindex Orgtbl mode

Due to Org's success in handling tables with Orgtbl, a frequently
requested feature is the use of Org's table functions in other modes,
e.g., @LaTeX{}.  This would be hard to do in a general way without
complicated customization nightmares.  Moreover, that would take Org
away from its simplicity roots that Orgtbl has proven.  There is,
however, an alternate approach to accomplishing the same.

This approach involves implementing a custom @emph{translate} function that
operates on a native Org @emph{source table} to produce a table in another
format.  This strategy would keep the excellently working Orgtbl
simple and isolate complications, if any, confined to the translate
function.  To add more alien table formats, we just add more translate
functions.  Also the burden of developing custom translate functions
for new table formats is in the hands of those who know those formats
best.

@menu
* Radio tables::                 Sending and receiving radio tables.
* A @LaTeX{} example::           Step by step, almost a tutorial.
* Translator functions::         Copy and modify.
@end menu

@node Radio tables
@appendixsubsec Radio tables

@cindex radio tables

Radio tables are target locations for translated tables that are not near
their source.  Org finds the target location and inserts the translated
table.

The key to finding the target location is the magic words @samp{BEGIN/END
RECEIVE ORGTBL}.  They have to appear as comments in the current mode.
If the mode is C, then:

@example
/* BEGIN RECEIVE ORGTBL table_name */
/* END RECEIVE ORGTBL table_name */
@end example

At the location of source, Org needs a special line to direct Orgtbl
to translate and to find the target for inserting the translated
table.  For example:

@cindex @samp{ORGTBL}, keyword
@example
#+ORGTBL: SEND table_name translation_function arguments ...
@end example


@noindent
@samp{table_name} is the table's reference name, which is also used in the
receiver lines, and the @samp{translation_function} is the Lisp function
that translates.  This line, in addition, may also contain alternating
key and value arguments at the end.  The translation function gets
these values as a property list.  A few standard parameters are
already recognized and acted upon before the translation function is
called:

@table @asis
@item @samp{:skip N}
Skip the first N lines of the table.  Hlines do count; include them
if they are to be skipped.

@item @samp{:skipcols (n1 n2 ...)}
List of columns to be skipped.  First Org automatically discards
columns with calculation marks and then sends the table to the
translator function, which then skips columns as specified in
@samp{skipcols}.
@end table

To keep the source table intact in the buffer without being disturbed
when the source file is compiled or otherwise being worked on, use one
of these strategies:

@itemize
@item
Place the table in a block comment.  For example, in C mode you
could wrap the table between @samp{/*} and @samp{*/} lines.

@item
Put the table after an ``end'' statement.  For example @code{\bye} in @TeX{}
and @code{\end@{document@}} in @LaTeX{}.

@item
Comment and un-comment each line of the table during edits.  The
@kbd{M-x orgtbl-toggle-comment} command makes toggling easy.
@end itemize

@node A @LaTeX{} example
@appendixsubsec A @LaTeX{} example of radio tables

@cindex @LaTeX{}, and Orgtbl mode

To wrap a source table in @LaTeX{}, use the @samp{comment} environment
provided by @samp{comment.sty}@footnote{@uref{https://www.ctan.org/pkg/comment}}.  To activate it, put
@code{\usepackage@{comment@}} in the document header.  Orgtbl mode inserts
a radio table skeleton@footnote{By default this works only for @LaTeX{}, HTML, and Texinfo.
Configure the variable @code{orgtbl-radio-table-templates} to install
templates for other modes.} with the command @kbd{M-x orgtbl-insert-radio-table}, which prompts for a table name.  For
example, if @samp{salesfigures} is the name, the template inserts:

@example
% BEGIN RECEIVE ORGTBL salesfigures
% END RECEIVE ORGTBL salesfigures
\begin@{comment@}
#+ORGTBL: SEND salesfigures orgtbl-to-latex
| | |
\end@{comment@}
@end example

@vindex LaTeX-verbatim-environments
@noindent
The line @samp{#+ORGTBL: SEND} tells Orgtbl mode to use the function
@code{orgtbl-to-latex} to convert the table to @LaTeX{} format, then insert
the table at the target (receive) location named @samp{salesfigures}.  Now
the table is ready for data entry.  It can even use spreadsheet
features@footnote{If the @samp{TBLFM} keyword contains an odd number of dollar
characters, this may cause problems with Font Lock in @LaTeX{} mode.  As
shown in the example you can fix this by adding an extra line inside
the @samp{comment} environment that is used to balance the dollar
expressions.  If you are using AUC@TeX{} with the font-latex library,
a much better solution is to add the @samp{comment} environment to the
variable @code{LaTeX-verbatim-environments}.}:

@example
% BEGIN RECEIVE ORGTBL salesfigures
% END RECEIVE ORGTBL salesfigures
\begin@{comment@}
#+ORGTBL: SEND salesfigures orgtbl-to-latex
| Month | Days | Nr sold | per day |
|-------+------+---------+---------|
| Jan   |   23 |      55 |     2.4 |
| Feb   |   21 |      16 |     0.8 |
| March |   22 |     278 |    12.6 |
#+TBLFM: $4=$3/$2;%.1f
% $ (optional extra dollar to keep Font Lock happy, see footnote)
\end@{comment@}
@end example

After editing, @kbd{C-c C-c} inserts the translated table at the
target location, between the two marker lines.

For hand-made custom tables, note that the translator needs to skip
the first two lines of the source table.  Also the command has to
@emph{splice} out the target table without the header and footer.

@example
\begin@{tabular@}@{lrrr@}
Month & \multicolumn@{1@}@{c@}@{Days@} & Nr.\ sold & per day\\
% BEGIN RECEIVE ORGTBL salesfigures
% END RECEIVE ORGTBL salesfigures
\end@{tabular@}
%
\begin@{comment@}
#+ORGTBL: SEND salesfigures orgtbl-to-latex :splice t :skip 2
| Month | Days | Nr sold | per day |
|-------+------+---------+---------|
| Jan   |   23 |      55 |     2.4 |
| Feb   |   21 |      16 |     0.8 |
| March |   22 |     278 |    12.6 |
#+TBLFM: $4=$3/$2;%.1f
\end@{comment@}
@end example

The @LaTeX{} translator function @code{orgtbl-to-latex} is already part of
Orgtbl mode and uses a @samp{tabular} environment to typeset the table and
marks horizontal lines with @code{\hline}.  For additional parameters to
control output, see @ref{Translator functions}:

@table @asis
@item @samp{:splice BOOLEAN}
When @{@{@{var(BOOLEAN@}@}@} is non-@code{nil}, return only table body lines;
i.e., not wrapped in @samp{tabular} environment.  Default is @code{nil}.

@item @samp{:fmt FMT}
Format string to warp each field.  It should contain @samp{%s} for the
original field value.  For example, to wrap each field value in
dollar symbol, you could use @samp{:fmt "$%s$"}.  Format can also wrap
a property list with column numbers and formats, for example @samp{:fmt
  (2 "$%s$" 4 "%s\\%%")}.  In place of a string, a function of one
argument can be used; the function must return a formatted string.

@item @samp{:efmt EFMT}
Format numbers as exponentials.  The spec should have @samp{%s} twice for
inserting mantissa and exponent, for example @samp{"%s\\times10^@{%s@}"}.  This
may also be a property list with column numbers and formats, for
example @samp{:efmt (2 "$%s\\times10^@{%s@}$" 4 "$%s\\cdot10^@{%s@}$")}.  After
@var{EFMT} has been applied to a value, @var{FMT}---see
above---is also applied.  Functions with two arguments can be
supplied instead of strings.  By default, no special formatting is
applied.
@end table

@node Translator functions
@appendixsubsec Translator functions

@cindex HTML, and Orgtbl mode
@cindex translator function

@findex orgtbl-to-csv
@findex orgtbl-to-tsv
@findex orgtbl-to-latex
@findex orgtbl-to-html
@findex orgtbl-to-texinfo
@findex orgtbl-to-unicode
@findex orgtbl-to-orgtbl
@findex orgtbl-to-generic
Orgtbl mode has built-in translator functions: @code{orgtbl-to-csv}
(comma-separated values), @code{orgtbl-to-tsv} (TAB-separated values),
@code{orgtbl-to-latex}, @code{orgtbl-to-html}, @code{orgtbl-to-texinfo},
@code{orgtbl-to-unicode} and @code{orgtbl-to-orgtbl}.  They use the generic
translator, @code{orgtbl-to-generic}, which delegates translations to
various export back-ends.

Properties passed to the function through the @samp{ORGTBL SEND} line take
precedence over properties defined inside the function.  For example,
this overrides the default @LaTeX{} line endings, @code{\\}, with @code{\\[2mm]}:

@example
#+ORGTBL: SEND test orgtbl-to-latex :lend " \\\\[2mm]"
@end example


For a new language translator, define a converter function.  It can be
a generic function, such as shown in this example.  It marks
a beginning and ending of a table with @samp{!BTBL!} and @samp{!ETBL!};
a beginning and ending of lines with @samp{!BL!} and @samp{!EL!}; and uses a TAB
for a field separator:

@lisp
(defun orgtbl-to-language (table params)
  "Convert the orgtbl-mode TABLE to language."
  (orgtbl-to-generic
   table
   (org-combine-plists
    '(:tstart "!BTBL!" :tend "!ETBL!" :lstart "!BL!" :lend "!EL!" :sep "\t")
    params)))
@end lisp

@noindent
The documentation for the @code{orgtbl-to-generic} function shows
a complete list of parameters, each of which can be passed through to
@code{orgtbl-to-latex}, @code{orgtbl-to-texinfo}, and any other function using
that generic function.

For complicated translations the generic translator function could be
replaced by a custom translator function.  Such a custom function must
take two arguments and return a single string containing the formatted
table.  The first argument is the table whose lines are a list of
fields or the symbol @code{hline}.  The second argument is the property
list consisting of parameters specified in the @samp{#+ORGTBL: SEND} line.
Please share your translator functions by posting them to the Org
users mailing list, at @email{emacs-orgmode@@gnu.org}.

@node Dynamic Blocks
@appendixsec Dynamic Blocks

@cindex dynamic blocks

Org supports @emph{dynamic blocks} in Org documents.  They are inserted
with begin and end markers like any other code block, but the contents
are updated automatically by a user function.

@kindex C-c C-x x
@findex org-dynamic-block-insert-dblock
You can insert a dynamic block with @code{org-dynamic-block-insert-dblock},
which is bound to @kbd{C-c C-x x} by default.  For example,
@kbd{C-c C-x x c l o c k t a b l e @key{RET}} inserts a table that
updates the work time (see @ref{Clocking Work Time}).

Dynamic blocks can have names and function parameters.  The syntax is
similar to source code block specifications:

@example
#+BEGIN: myblock :parameter1 value1 :parameter2 value2 ...
  ...
#+END:
@end example

These commands update dynamic blocks:

@table @asis
@item @kbd{C-c C-x C-u} (@code{org-dblock-update})
@kindex C-c C-x C-u
@findex org-dblock-update
Update dynamic block at point.

@item @kbd{C-u C-c C-x C-u}
@kindex C-u C-c C-x C-u
Update all dynamic blocks in the current file.
@end table

Before updating a dynamic block, Org removes content between the
@samp{BEGIN} and @samp{END} markers.  Org then reads the parameters on the
@samp{BEGIN} line for passing to the writer function as a plist. The
previous content of the dynamic block becomes erased from the buffer
and appended to the plist under @code{:content}.

The syntax for naming a writer function with a dynamic block labelled
@samp{myblock} is: @code{org-dblock-write:myblock}.

The following is an example of a dynamic block and a block writer function
that updates the time when the function was last run:

@example
#+BEGIN: block-update-time :format "on %m/%d/%Y at %H:%M"
  ...
#+END:
@end example

@noindent
The dynamic block's writer function:

@lisp
(defun org-dblock-write:block-update-time (params)
  (let ((fmt (or (plist-get params :format) "%d. %m. %Y")))
    (insert "Last block update at: "
            (format-time-string fmt))))
@end lisp

To keep dynamic blocks up-to-date in an Org file, use the function,
@code{org-update-all-dblocks} in hook, such as @code{before-save-hook}.  The
@code{org-update-all-dblocks} function does not run if the file is not in
Org mode.

@findex org-narrow-to-block
Dynamic blocks, like any other block, can be narrowed with
@code{org-narrow-to-block}.

@node Special Agenda Views
@appendixsec Special Agenda Views

@cindex agenda views, user-defined

@vindex org-agenda-skip-function
@vindex org-agenda-skip-function-global
Org provides a special hook to further limit items in agenda views:
@code{agenda}, @code{agenda*}@footnote{The @code{agenda*} view is the same as @code{agenda} except that it
only considers @emph{appointments}, i.e., scheduled and deadline items that
have a time specification @samp{[h]h:mm} in their time-stamps.}, @code{todo}, @code{alltodo}, @code{tags}, @code{tags-todo},
@code{tags-tree}.  Specify a custom function that tests inclusion of every
matched item in the view.  This function can also skip as much as is
needed.

For a global condition applicable to agenda views, use the
@code{org-agenda-skip-function-global} variable.  Org uses a global
condition with @code{org-agenda-skip-function} for custom searching.

This example defines a function for a custom view showing TODO items
with @samp{waiting} status.  Manually this is a multi-step search process,
but with a custom view, this can be automated as follows:

The custom function searches the subtree for the @samp{waiting} tag and
returns @code{nil} on match.  Otherwise it gives the location from where
the search continues.

@lisp
(defun my-skip-unless-waiting ()
  "Skip trees that are not waiting"
  (let ((subtree-end (save-excursion (org-end-of-subtree t))))
    (if (re-search-forward ":waiting:" subtree-end t)
        nil          ; tag found, do not skip
      subtree-end))) ; tag not found, continue after end of subtree
@end lisp

To use this custom function in a custom agenda command:

@lisp
(org-add-agenda-custom-command
 '("b" todo "PROJECT"
   ((org-agenda-skip-function 'my-skip-unless-waiting)
    (org-agenda-overriding-header "Projects waiting for something: "))))
@end lisp

@vindex org-agenda-overriding-header
Note that this also binds @code{org-agenda-overriding-header} to a more
meaningful string suitable for the agenda view.

@vindex org-odd-levels-only
@vindex org-agenda-skip-function
Search for entries with a limit set on levels for the custom search.
This is a general approach to creating custom searches in Org.  To
include all levels, use @samp{LEVEL>0}@footnote{Note that, for @code{org-odd-levels-only}, a level number
corresponds to order in the hierarchy, not to the number of stars.}.  Then to selectively pick
the matched entries, use @code{org-agenda-skip-function}, which also
accepts Lisp forms, such as @code{org-agenda-skip-entry-if} and
@code{org-agenda-skip-subtree-if}.  For example:

@table @asis
@item @samp{(org-agenda-skip-entry-if 'scheduled)}
Skip current entry if it has been scheduled.

@item @samp{(org-agenda-skip-entry-if 'notscheduled)}
Skip current entry if it has not been scheduled.

@item @samp{(org-agenda-skip-entry-if 'deadline)}
Skip current entry if it has a deadline.

@item @samp{(org-agenda-skip-entry-if 'scheduled 'deadline)}
Skip current entry if it has a deadline, or if it is scheduled.

@item @samp{(org-agenda-skip-entry-if 'todo '("TODO" "WAITING"))}
Skip current entry if the TODO keyword is TODO or WAITING@.

@item @samp{(org-agenda-skip-entry-if 'todo 'done)}
Skip current entry if the TODO keyword marks a DONE state.

@item @samp{(org-agenda-skip-entry-if 'timestamp)}
Skip current entry if it has any timestamp, may also be deadline or
scheduled.

@item @samp{(org-agenda-skip-entry-if 'regexp "regular expression")}
Skip current entry if the regular expression matches in the entry.

@item @samp{(org-agenda-skip-entry-if 'notregexp "regular expression")}
Skip current entry unless the regular expression matches.

@item @samp{(org-agenda-skip-subtree-if 'regexp "regular expression")}
Same as above, but check and skip the entire subtree.
@end table

The following is an example of a search for @samp{waiting} without the
special function:

@lisp
(org-add-agenda-custom-command
 '("b" todo "PROJECT"
   ((org-agenda-skip-function '(org-agenda-skip-subtree-if
                                'regexp ":waiting:"))
    (org-agenda-overriding-header "Projects waiting for something: "))))
@end lisp

@node Speeding Up Your Agendas
@appendixsec Speeding Up Your Agendas

@cindex agenda views, optimization

Some agenda commands slow down when the Org files grow in size or
number.  Here are tips to speed up:

@itemize
@item
Reduce the number of Org agenda files to avoid slowdowns due to hard drive
accesses.

@item
Reduce the number of DONE and archived headlines so agenda
operations that skip over these can finish faster.

@item
Do not dim blocked tasks:
@vindex org-agenda-dim-blocked-tasks

@lisp
(setq org-agenda-dim-blocked-tasks nil)
@end lisp

@item
Stop preparing agenda buffers on startup:
@vindex org-startup-folded
@vindex org-agenda-inhibit-startup

@lisp
(setq org-agenda-inhibit-startup t)
@end lisp

@item
Disable tag inheritance for agendas:
@vindex org-agenda-show-inherited-tags
@vindex org-agenda-use-tag-inheritance

@lisp
(setq org-agenda-use-tag-inheritance nil)
@end lisp
@end itemize

These options can be applied to selected agenda views.  For more
details about generation of agenda views, see the docstrings for the
relevant variables, and this @uref{https://orgmode.org/worg/agenda-optimization.html, dedicated Worg page} for agenda
optimization.

@node Extracting Agenda Information
@appendixsec Extracting Agenda Information

@cindex agenda, pipe
@cindex scripts, for agenda processing

Org provides commands to access agendas through Emacs batch mode.
Through this command-line interface, agendas are automated for further
processing or printing.

@vindex org-agenda-custom-commands
@findex org-batch-agenda
@code{org-batch-agenda} creates an agenda view in ASCII and outputs to
standard output.  This command takes one string parameter.  When
string consists of a single character, Org uses it as a key to
@code{org-agenda-custom-commands}.  These are the same ones available
through the agenda dispatcher (see @ref{Agenda Dispatcher}).

This example command line directly prints the TODO list to the printer:

@example
emacs -batch -l ~/.emacs -eval '(org-batch-agenda "t")' | lpr
@end example


When the string parameter length is two or more characters, Org
matches it with tags/TODO strings.  For example, this example command
line prints items tagged with @samp{shop}, but excludes items tagged with
@samp{NewYork}:

@example
emacs -batch -l ~/.emacs                                      \
      -eval '(org-batch-agenda "+shop-NewYork")' | lpr
@end example

@noindent
An example showing on-the-fly parameter modifications:

@example
emacs -batch -l ~/.emacs                                      \
   -eval '(org-batch-agenda "a"                               \
           org-agenda-span (quote month)                      \
           org-agenda-include-diary nil                       \
           org-agenda-files (quote ("~/org/project.org")))'   \
   | lpr
@end example

@noindent
which produces an agenda for the next 30 days from just the
@samp{~/org/projects.org} file.

@findex org-batch-agenda-csv
For structured processing of agenda output, use @code{org-batch-agenda-csv}
with the following fields:

@table @asis
@item category
The category of the item
@item head
The headline, without TODO keyword, TAGS and PRIORITY
@item type
The type of the agenda entry, can be

@multitable {aaaaaaaaaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa}
@item @code{todo}
@tab selected in TODO match
@item @code{tagsmatch}
@tab selected in tags match
@item @code{diary}
@tab imported from diary
@item @code{deadline}
@tab a deadline
@item @code{scheduled}
@tab scheduled
@item @code{timestamp}
@tab appointment, selected by timestamp
@item @code{closed}
@tab entry was closed on date
@item @code{upcoming-deadline}
@tab warning about nearing deadline
@item @code{past-scheduled}
@tab forwarded scheduled item
@item @code{block}
@tab entry has date block including date
@end multitable

@item todo
The TODO keyword, if any
@item tags
All tags including inherited ones, separated by colons
@item date
The relevant date, like @samp{2007-2-14}
@item time
The time, like @samp{15:00-16:50}
@item extra
String with extra planning info
@item priority-l
The priority letter if any was given
@item priority-n
The computed numerical priority
@end table

If the selection of the agenda item was based on a timestamp,
including those items with @samp{DEADLINE} and @samp{SCHEDULED} keywords, then
Org includes date and time in the output.

If the selection of the agenda item was based on a timestamp  (or
deadline/scheduled), then Org includes date and time in the output.

Here is an example of a post-processing script in Perl.  It takes the
CSV output from Emacs and prints with a checkbox:

@example
#!/usr/bin/perl

# define the Emacs command to run
$cmd = "emacs -batch -l ~/.emacs -eval '(org-batch-agenda-csv \"t\")'";

# run it and capture the output
$agenda = qx@{$cmd 2>/dev/null@};

# loop over all lines
foreach $line (split(/\n/,$agenda)) @{
    # get the individual values
    ($category,$head,$type,$todo,$tags,$date,$time,$extra,
     $priority_l,$priority_n) = split(/,/,$line);
    # process and print
    print "[ ] $head\n";
@}
@end example

@node Using the Property API
@appendixsec Using the Property API

@cindex API, for properties
@cindex properties, API

Here is a description of the functions that can be used to work with
properties.

@defun org-entry-properties &optional pom which
Get all properties of the entry at point-or-marker @var{POM}.
This includes the TODO keyword, the tags, time strings for deadline,
scheduled, and clocking, and any additional properties defined in the
entry.  The return value is an alist.  Keys may occur multiple times
if the property key was used several times.  @var{POM} may also
be @code{nil}, in which case the current entry is used.  If
@var{WHICH} is @code{nil} or @code{all}, get all properties.  If
@var{WHICH} is @code{special} or @code{standard}, only get that subclass.
@end defun

@vindex org-use-property-inheritance
@findex org-insert-property-drawer
@defun org-entry-get pom property &optional inherit
Get value of @var{PROPERTY} for entry at point-or-marker
@var{POM}.  By default, this only looks at properties defined
locally in the entry.  If @var{INHERIT} is non-@code{nil} and the
entry does not have the property, then also check higher levels of the
hierarchy.  If @var{INHERIT} is the symbol @code{selective}, use
inheritance if and only if the setting of
@code{org-use-property-inheritance} selects @var{PROPERTY} for
inheritance.
@end defun

@defun org-entry-delete pom property
Delete the property @var{PROPERTY} from entry at point-or-marker
@var{POM}.
@end defun

@defun org-entry-put pom property value
Set @var{PROPERTY} to @var{VALUES} for entry at
point-or-marker POM@.
@end defun

@defun org-buffer-property-keys &optional include-specials
Get all property keys in the current buffer.
@end defun

@defun org-insert-property-drawer
Insert a property drawer for the current entry.  Also
@end defun

@defun org-entry-put-multivalued-property pom property &rest values
Set @var{PROPERTY} at point-or-marker @var{POM} to
@var{VALUES}.  @var{VALUES} should be a list of strings.
They are concatenated, with spaces as separators.
@end defun

@defun org-entry-get-multivalued-property pom property
Treat the value of the property @var{PROPERTY} as
a whitespace-separated list of values and return the values as a list
of strings.
@end defun

@defun org-entry-add-to-multivalued-property pom property value
Treat the value of the property @var{PROPERTY} as
a whitespace-separated list of values and make sure that
@var{VALUE} is in this list.
@end defun

@defun org-entry-remove-from-multivalued-property pom property value
Treat the value of the property @var{PROPERTY} as
a whitespace-separated list of values and make sure that
@var{VALUE} is @emph{not} in this list.
@end defun

@defun org-entry-member-in-multivalued-property pom property value
Treat the value of the property @var{PROPERTY} as
a whitespace-separated list of values and check if @var{VALUE} is
in this list.
@end defun

@defopt org-property-allowed-value-functions
Hook for functions supplying allowed values for a specific property.
The functions must take a single argument, the name of the property,
and return a flat list of allowed values.  If @samp{:ETC} is one of the
values, use the values as completion help, but allow also other values
to be entered.  The functions must return @code{nil} if they are not
responsible for this property.
@end defopt

@node Using the Mapping API
@appendixsec Using the Mapping API

@cindex API, for mapping
@cindex mapping entries, API

Org has sophisticated mapping capabilities to find all entries
satisfying certain criteria.  Internally, this functionality is used
to produce agenda views, but there is also an API that can be used to
execute arbitrary functions for each or selected entries.  The main
entry point for this API is:

@defun org-map-entries func &optional match scope &rest skip
Call @var{FUNC} at each headline selected by @var{MATCH} in
@var{SCOPE}.

@var{FUNC} is a function or a Lisp form.  With point positioned
at the beginning of the headline, call the function without arguments.
Org returns an alist of return values of calls to the function.

To avoid preserving point, Org wraps the call to @var{FUNC} in
@code{save-excursion} form.  After evaluation, Org moves point to the end
of the line that was just processed.  Search continues from that point
forward.  This may not always work as expected under some conditions,
such as if the current sub-tree was removed by a previous archiving
operation.  In such rare circumstances, Org skips the next entry
entirely when it should not.  To stop Org from such skips, make
@var{FUNC} set the variable @code{org-map-continue-from} to a specific
buffer position.

@var{MATCH} is a tags/property/TODO match.  Org iterates only
matched headlines.  Org iterates over all headlines when
@var{MATCH} is @code{nil} or @code{t}.

@var{SCOPE} determines the scope of this command.  It can be any
of:

@table @asis
@item @code{nil}
The current buffer, respecting the restriction, if any.

@item @code{tree}
The subtree started with the entry at point.

@item @code{region}
The entries within the active region, if any.

@item @code{file}
The current buffer, without restriction.

@item @code{file-with-archives}
The current buffer, and any archives associated with it.

@item @code{agenda}
All agenda files.

@item @code{agenda-with-archives}
All agenda files with any archive files associated with them.

@item list of filenames
If this is a list, all files in the list are scanned.
@end table

@noindent
The remaining arguments are treated as settings for the scanner's
skipping facilities.  Valid arguments are:

@table @asis
@item @code{archive}
Skip trees with the @samp{ARCHIVE} tag.

@item @code{comment}
Skip trees with the COMMENT keyword.

@item function or Lisp form
@vindex org-agenda-skip-function
Used as value for @code{org-agenda-skip-function}, so whenever the
function returns @code{t}, @var{FUNC} is called for that entry and
search continues from the point where the function leaves it.
@end table
@end defun

The mapping routine can call any arbitrary function, even functions
that change meta data or query the property API (see @ref{Using the Property API}).  Here are some handy functions:

@defun org-todo &optional arg
Change the TODO state of the entry.  See the docstring of the
functions for the many possible values for the argument
@var{ARG}.
@end defun

@defun org-priority &optional action
Change the priority of the entry.  See the docstring of this function
for the possible values for @var{ACTION}.
@end defun

@defun org-toggle-tag tag &optional onoff
Toggle the tag @var{TAG} in the current entry.  Setting
@var{ONOFF} to either @code{on} or @code{off} does not toggle tag, but
ensure that it is either on or off.
@end defun

@defun org-promote
Promote the current entry.
@end defun

@defun org-demote
Demote the current entry.
@end defun

This example turns all entries tagged with @samp{TOMORROW} into TODO
entries with keyword @samp{UPCOMING}.  Org ignores entries in comment trees
and archive trees.

@lisp
(org-map-entries '(org-todo "UPCOMING")
                 "+TOMORROW" 'file 'archive 'comment)
@end lisp

The following example counts the number of entries with TODO keyword
@samp{WAITING}, in all agenda files.

@lisp
(length (org-map-entries t "/+WAITING" 'agenda))
@end lisp

@node History and Acknowledgments
@appendix History and Acknowledgments



@anchor{From Carsten}
@appendixsec From Carsten

Org was born in 2003, out of frustration over the user interface of
the Emacs Outline mode.  I was trying to organize my notes and
projects, and using Emacs seemed to be the natural way to go.
However, having to remember eleven different commands with two or
three keys per command, only to hide and show parts of the outline
tree, that seemed entirely unacceptable to me.  Also, when using
outlines to take notes, I constantly wanted to restructure the tree,
organizing it parallel to my thoughts and plans.  @emph{Visibility cycling}
and @emph{structure editing} were originally implemented in the package
@samp{outline-magic.el}, but quickly moved to the more general @samp{org.el}.
As this environment became comfortable for project planning, the next
step was adding @emph{TODO entries}, basic @emph{timestamps}, and @emph{table
support}.  These areas highlighted the two main goals that Org still
has today: to be a new, outline-based, plain text mode with innovative
and intuitive editing features, and to incorporate project planning
functionality directly into a notes file.

Since the first release, literally thousands of emails to me or to the
@email{emacs-orgmode@@gnu.org, mailing list} have provided a constant stream of bug reports, feedback,
new ideas, and sometimes patches and add-on code.  Many thanks to
everyone who has helped to improve this package.  I am trying to keep
here a list of the people who had significant influence in shaping one
or more aspects of Org.  The list may not be complete, if I have
forgotten someone, please accept my apologies and let me know.

Before I get to this list, a few special mentions are in order:

@table @asis
@item Bastien Guerry
Bastien has written a large number of extensions to Org (most of
them integrated into the core by now), including the @LaTeX{} exporter
and the plain list parser.  His support during the early days was
central to the success of this project.  Bastien also invented Worg,
helped establishing the Web presence of Org, and sponsored hosting
costs for the orgmode.org website.  Bastien stepped in as maintainer
of Org between 2011 and 2013, at a time when I desperately needed
a break.

@item Eric Schulte and Dan Davison
Eric and Dan are jointly responsible for the Org Babel system, which
turns Org into a multi-language environment for evaluating code and
doing literate programming and reproducible research.  This has
become one of Org's killer features that define what Org is today.

@item John Wiegley
John has contributed a number of great ideas and patches directly to
Org, including the attachment system (@samp{org-attach.el}), integration
with Apple Mail (@samp{org-mac-message.el}), hierarchical dependencies of
TODO items, habit tracking (@samp{org-habits.el}), and encryption
(@samp{org-crypt.el}).  Also, the capture system is really an extended
copy of his great @samp{remember.el}.

@item Sebastian Rose
Without Sebastian, the HTML/XHTML publishing of Org would be the
pitiful work of an ignorant amateur.  Sebastian has pushed this part
of Org onto a much higher level.  He also wrote @samp{org-info.js},
a JavaScript program for displaying webpages derived from Org using
an Info-like or a folding interface with single-key navigation.
@end table

See below for the full list of contributions! Again, please let me
know what I am missing here!

@anchor{From Bastien}
@appendixsec From Bastien

I (Bastien) have been maintaining Org between 2011 and 2013.  This
appendix would not be complete without adding a few more
acknowledgments and thanks.

I am first grateful to Carsten for his trust while handing me over the
maintainership of Org.  His unremitting support is what really helped
me getting more confident over time, with both the community and the
code.

When I took over maintainership, I knew I would have to make Org more
collaborative than ever, as I would have to rely on people that are
more knowledgeable than I am on many parts of the code.  Here is
a list of the persons I could rely on, they should really be
considered co-maintainers, either of the code or the community:

@table @asis
@item Eric Schulte
Eric is maintaining the Babel parts of Org.  His reactivity here
kept me away from worrying about possible bugs here and let me focus
on other parts.

@item Nicolas Goaziou
Nicolas is maintaining the consistency of the deepest parts of Org.
His work on @samp{org-element.el} and @samp{ox.el} has been outstanding, and
it opened the doors for many new ideas and features.  He rewrote
many of the old exporters to use the new export engine, and helped
with documenting this major change.  More importantly (if that's
possible), he has been more than reliable during all the work done
for Org 8.0, and always very reactive on the mailing list.

@item Achim Gratz
Achim rewrote the building process of Org, turning some @emph{ad hoc}
tools into a flexible and conceptually clean process.  He patiently
coped with the many hiccups that such a change can create for users.

@item Nick Dokos
The Org mode mailing list would not be such a nice place without
Nick, who patiently helped users so many times.  It is impossible to
overestimate such a great help, and the list would not be so active
without him.
@end table

I received support from so many users that it is clearly impossible to
be fair when shortlisting a few of them, but Org's history would not
be complete if the ones above were not mentioned in this manual.

@anchor{List of Contributions}
@appendixsec List of Contributions

@itemize
@item
Russel Adams came up with the idea for drawers.

@item
Thomas Baumann wrote @samp{ol-bbdb.el} and @samp{ol-mhe.el}.

@item
Christophe Bataillon created the great unicorn logo that we use on
the Org mode website.

@item
Alex Bochannek provided a patch for rounding timestamps.

@item
Jan Böcker wrote @samp{ol-docview.el}.

@item
Brad Bozarth showed how to pull RSS feed data into Org files.

@item
Tom Breton wrote @samp{org-choose.el}.

@item
Charles Cave's suggestion sparked the implementation of templates
for Remember, which are now templates for capture.

@item
Pavel Chalmoviansky influenced the agenda treatment of items with
specified time.

@item
Gregory Chernov patched support for Lisp forms into table
calculations and improved XEmacs compatibility, in particular by
porting @samp{nouline.el} to XEmacs.

@item
Sacha Chua suggested copying some linking code from Planner.

@item
Baoqiu Cui contributed the DocBook exporter.

@item
Eddward DeVilla proposed and tested checkbox statistics.  He also
came up with the idea of properties, and that there should be an API
for them.

@item
Nick Dokos tracked down several nasty bugs.

@item
Kees Dullemond used to edit projects lists directly in HTML and so
inspired some of the early development, including HTML export.  He
also asked for a way to narrow wide table columns.

@item
Thomas@tie{}S@.@tie{}Dye contributed documentation on Worg and helped
integrating the Org Babel documentation into the manual.

@item
Christian Egli converted the documentation into Texinfo format,
inspired the agenda, patched CSS formatting into the HTML exporter,
and wrote @samp{org-taskjuggler.el}.

@item
David Emery provided a patch for custom CSS support in exported HTML
agendas.

@item
Nic Ferrier contributed mailcap and XOXO support.

@item
Miguel@tie{}A@.@tie{}Figueroa-Villanueva implemented hierarchical checkboxes.

@item
John Foerch figured out how to make incremental search show context
around a match in a hidden outline tree.

@item
Raimar Finken wrote @samp{org-git-line.el}.

@item
Mikael Fornius works as a mailing list moderator.

@item
Austin Frank works as a mailing list moderator.

@item
Eric Fraga drove the development of Beamer export with ideas and
testing.

@item
Barry Gidden did proofreading the manual in preparation for the book
publication through Network Theory Ltd.

@item
Niels Giesen had the idea to automatically archive DONE trees.

@item
Nicolas Goaziou rewrote much of the plain list code.

@item
Kai Grossjohann pointed out key-binding conflicts with other
packages.

@item
Brian Gough of Network Theory Ltd publishes the Org mode manual as
a book.

@item
Bernt Hansen has driven much of the support for auto-repeating
tasks, task state change logging, and the clocktable.  His clear
explanations have been critical when we started to adopt the Git
version control system.

@item
Manuel Hermenegildo has contributed various ideas, small fixes and
patches.

@item
Phil Jackson wrote @samp{ol-irc.el}.

@item
Scott Jaderholm proposed footnotes, control over whitespace between
folded entries, and column view for properties.

@item
Matt Jones wrote MobileOrg Android.

@item
Tokuya Kameshima wrote @samp{org-wl.el} and @samp{org-mew.el}.

@item
Shidai Liu (``Leo'') asked for embedded @LaTeX{} and tested it.  He also
provided frequent feedback and some patches.

@item
Matt Lundin has proposed last-row references for table formulas and
named invisible anchors.  He has also worked a lot on the FAQ@.

@item
David Maus wrote @samp{org-atom.el}, maintains the issues file for Org,
and is a prolific contributor on the mailing list with competent
replies, small fixes and patches.

@item
Jason@tie{}F@.@tie{}McBrayer suggested agenda export to CSV format.

@item
Max Mikhanosha came up with the idea of refiling.

@item
Dmitri Minaev sent a patch to set priority limits on a per-file
basis.

@item
Stefan Monnier provided a patch to keep the Emacs Lisp compiler
happy.

@item
Richard Moreland wrote MobileOrg for the iPhone.

@item
Rick Moynihan proposed allowing multiple TODO sequences in a file
and being able to quickly restrict the agenda to a subtree.

@item
Todd Neal provided patches for links to Info files and Elisp forms.

@item
Greg Newman refreshed the unicorn logo into its current form.

@item
Tim O'Callaghan suggested in-file links, search options for general
file links, and tags.

@item
Osamu Okano wrote @samp{orgcard2ref.pl}, a Perl program to create a text
version of the reference card.

@item
Takeshi Okano translated the manual and David O'Toole's tutorial
into Japanese.

@item
Oliver Oppitz suggested multi-state TODO items.

@item
Scott Otterson sparked the introduction of descriptive text for
links, among other things.

@item
Pete Phillips helped during the development of the TAGS feature,
and provided frequent feedback.

@item
Martin Pohlack provided the code snippet to bundle character
insertion into bundles of 20 for undo.

@item
T@.@tie{}V@.@tie{}Raman reported bugs and suggested improvements.

@item
Matthias Rempe (Oelde) provided ideas, Windows support, and quality
control.

@item
Paul Rivier provided the basic implementation of named footnotes.
He also acted as mailing list moderator for some time.

@item
Kevin Rogers contributed code to access VM files on remote hosts.

@item
Frank Ruell solved the mystery of the @samp{keymapp nil} bug, a conflict
with @samp{allout.el}.

@item
Jason Riedy generalized the send-receive mechanism for Orgtbl
tables with extensive patches.

@item
Philip Rooke created the Org reference card, provided lots of
feedback, developed and applied standards to the Org documentation.

@item
Christian Schlauer proposed angular brackets around links, among
other things.

@item
Paul Sexton wrote @samp{org-ctags.el}.

@item
Tom Shannon's @samp{organizer-mode.el} inspired linking to VM/BBDB/Gnus.

@item
Ilya Shlyakhter proposed the Archive Sibling, line numbering in
literal examples, and remote highlighting for referenced code lines.

@item
Stathis Sideris wrote the @samp{ditaa.jar} ASCII to PNG converter that is
now packaged into Org's @samp{contrib/} directory.

@item
Daniel Sinder came up with the idea of internal archiving by locking
subtrees.

@item
Dale Smith proposed link abbreviations.

@item
James TD Smith has contributed a large number of patches for
useful tweaks and features.

@item
Adam Spiers asked for global linking commands, inspired the link
extension system, added support for Mairix, and proposed the mapping
API@.

@item
Ulf Stegemann created the table to translate special symbols to
HTML, @LaTeX{}, UTF-8, Latin-1 and ASCII@.

@item
Andy Stewart contributed code to @samp{ol-w3m.el}, to copy
HTML content with links transformation to Org syntax.

@item
David O'Toole wrote @samp{org-publish.el} and drafted the
manual chapter about publishing.

@item
Jambunathan@tie{}K@.@tie{}contributed the ODT exporter.

@item
Sebastien Vauban reported many issues with @LaTeX{} and Beamer export
and enabled source code highlighting in Gnus.

@item
Stefan Vollmar organized a video-recorded talk at the
Max-Planck-Institute for Neurology.  He also inspired the creation
of a concept index for HTML export.

@item
Jürgen Vollmer contributed code generating the table of contents in
HTML output.

@item
Samuel Wales has provided important feedback and bug reports.

@item
Chris Wallace provided a patch implementing the @samp{QUOTE} block.

@item
David Wainberg suggested archiving, and improvements to the
linking system.

@item
Carsten Wimmer suggested some changes and helped fix a bug in
linking to Gnus.

@item
Roland Winkler requested additional key bindings to make Org work on
a TTY@.

@item
Piotr Zielinski wrote @samp{org-mouse.el}, proposed agenda
blocks and contributed various ideas and code snippets.

@item
Marco Wahl wrote @samp{ol-eww.el}.
@end itemize

@node GNU Free Documentation License
@appendix GNU Free Documentation License

@center Version 1.3, 3 November 2008

@display
Copyright @copyright{} 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc.
@uref{http://fsf.org/}

Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.
@end display

@enumerate 0
@item
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We have designed this License in order to use it for manuals for
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@item
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network protocols a complete Transparent copy of the Document, free
of added material.  If you use the latter option, you must take
reasonably prudent steps, when you begin distribution of Opaque
copies in quantity, to ensure that this Transparent copy will
remain thus accessible at the stated location until at least one
year after the last time you distribute an Opaque copy (directly or
through your agents or retailers) of that edition to the public.

It is requested, but not required, that you contact the authors of
the Document well before redistributing any large number of copies,
to give them a chance to provide you with an updated version of the
Document.

@item
MODIFICATIONS

You may copy and distribute a Modified Version of the Document
under the conditions of sections 2 and 3 above, provided that you
release the Modified Version under precisely this License, with the
Modified Version filling the role of the Document, thus licensing
distribution and modification of the Modified Version to whoever
possesses a copy of it.  In addition, you must do these things in
the Modified Version:

@enumerate A
@item
Use in the Title Page (and on the covers, if any) a title
distinct from that of the Document, and from those of previous
versions (which should, if there were any, be listed in the
History section of the Document). You may use the same title as
a previous version if the original publisher of that version
gives permission.

@item
List on the Title Page, as authors, one or more persons or
entities responsible for authorship of the modifications in the
Modified Version, together with at least five of the principal
authors of the Document (all of its principal authors, if it has
fewer than five), unless they release you from this requirement.

@item
State on the Title page the name of the publisher of the
Modified Version, as the publisher.

@item
Preserve all the copyright notices of the Document.

@item
Add an appropriate copyright notice for your modifications
adjacent to the other copyright notices.

@item
Include, immediately after the copyright notices, a license
notice giving the public permission to use the Modified Version
under the terms of this License, in the form shown in the
Addendum below.

@item
Preserve in that license notice the full lists of Invariant
Sections and required Cover Texts given in the Document's
license notice.

@item
Include an unaltered copy of this License.

@item
Preserve the section Entitled ``History'', Preserve its Title, and
add to it an item stating at least the title, year, new authors,
and publisher of the Modified Version as given on the Title
Page. If there is no section Entitled ``History'' in the Document,
create one stating the title, year, authors, and publisher of
the Document as given on its Title Page, then add an item
describing the Modified Version as stated in the previous
sentence.

@item
Preserve the network location, if any, given in the Document
for public access to a Transparent copy of the Document, and
likewise the network locations given in the Document for
previous versions it was based on. These may be placed in the
``History'' section. You may omit a network location for a work
that was published at least four years before the Document
itself, or if the original publisher of the version it refers
to gives permission.

@item
For any section Entitled ``Acknowledgements'' or ``Dedications'',
Preserve the Title of the section, and preserve in the section
all the substance and tone of each of the contributor
acknowledgements and/or dedications given therein.

@item
Preserve all the Invariant Sections of the Document, unaltered
in their text and in their titles. Section numbers or the
equivalent are not considered part of the section titles.

@item
Delete any section Entitled ``Endorsements''. Such a section may
not be included in the Modified Version.

@item
Do not retitle any existing section to be Entitled
``Endorsements'' or to conflict in title with any Invariant
Section.

@item
Preserve any Warranty Disclaimers.
@end enumerate

If the Modified Version includes new front-matter sections or
appendices that qualify as Secondary Sections and contain no material
copied from the Document, you may at your option designate some or all
of these sections as invariant.  To do this, add their titles to the
list of Invariant Sections in the Modified Version's license notice.
These titles must be distinct from any other section titles.

You may add a section Entitled ``Endorsements'', provided it contains
nothing but endorsements of your Modified Version by various
parties---for example, statements of peer review or that the text has
been approved by an organization as the authoritative definition of a
standard.

You may add a passage of up to five words as a Front-Cover Text, and a
passage of up to 25 words as a Back-Cover Text, to the end of the list
of Cover Texts in the Modified Version.  Only one passage of
Front-Cover Text and one of Back-Cover Text may be added by (or
through arrangements made by) any one entity.  If the Document already
includes a cover text for the same cover, previously added by you or
by arrangement made by the same entity you are acting on behalf of,
you may not add another; but you may replace the old one, on explicit
permission from the previous publisher that added the old one.

The author(s) and publisher(s) of the Document do not by this License
give permission to use their names for publicity for or to assert or
imply endorsement of any Modified Version.

@item
COMBINING DOCUMENTS

You may combine the Document with other documents released under
this License, under the terms defined in section 4 above for
modified versions, provided that you include in the combination all
of the Invariant Sections of all of the original documents,
unmodified, and list them all as Invariant Sections of your
combined work in its license notice, and that you preserve all
their Warranty Disclaimers.

The combined work need only contain one copy of this License, and
multiple identical Invariant Sections may be replaced with a single
copy.  If there are multiple Invariant Sections with the same name
but different contents, make the title of each such section unique
by adding at the end of it, in parentheses, the name of the
original author or publisher of that section if known, or else
a unique number.  Make the same adjustment to the section titles in
the list of Invariant Sections in the license notice of the
combined work.

In the combination, you must combine any sections Entitled
``History'' in the various original documents, forming one section
Entitled ``History''; likewise combine any sections Entitled
``Acknowledgements'', and any sections Entitled ``Dedications''.  You
must delete all sections Entitled ``Endorsements.''

@item
COLLECTIONS OF DOCUMENTS

You may make a collection consisting of the Document and other
documents released under this License, and replace the individual
copies of this License in the various documents with a single copy
that is included in the collection, provided that you follow the
rules of this License for verbatim copying of each of the documents
in all other respects.

You may extract a single document from such a collection, and
distribute it individually under this License, provided you insert
a copy of this License into the extracted document, and follow this
License in all other respects regarding verbatim copying of that
document.

@item
AGGREGATION WITH INDEPENDENT WORKS

A compilation of the Document or its derivatives with other
separate and independent documents or works, in or on a volume of
a storage or distribution medium, is called an ``aggregate'' if the
copyright resulting from the compilation is not used to limit the
legal rights of the compilation's users beyond what the individual
works permit.  When the Document is included in an aggregate, this
License does not apply to the other works in the aggregate which
are not themselves derivative works of the Document.

If the Cover Text requirement of section 3 is applicable to these
copies of the Document, then if the Document is less than one half
of the entire aggregate, the Document's Cover Texts may be placed
on covers that bracket the Document within the aggregate, or the
electronic equivalent of covers if the Document is in electronic
form.  Otherwise they must appear on printed covers that bracket
the whole aggregate.

@item
TRANSLATION

Translation is considered a kind of modification, so you may
distribute translations of the Document under the terms of
section 4.  Replacing Invariant Sections with translations requires
special permission from their copyright holders, but you may
include translations of some or all Invariant Sections in addition
to the original versions of these Invariant Sections.  You may
include a translation of this License, and all the license notices
in the Document, and any Warranty Disclaimers, provided that you
also include the original English version of this License and the
original versions of those notices and disclaimers.  In case of
a disagreement between the translation and the original version of
this License or a notice or disclaimer, the original version will
prevail.

If a section in the Document is Entitled ``Acknowledgements'',
``Dedications'', or ``History'', the requirement (section 4) to
Preserve its Title (section 1) will typically require changing the
actual title.

@item
TERMINATION

You may not copy, modify, sublicense, or distribute the Document
except as expressly provided under this License.  Any attempt
otherwise to copy, modify, sublicense, or distribute it is void,
and will automatically terminate your rights under this License.

However, if you cease all violation of this License, then your
license from a particular copyright holder is reinstated (a)
provisionally, unless and until the copyright holder explicitly and
finally terminates your license, and (b) permanently, if the
copyright holder fails to notify you of the violation by some
reasonable means prior to 60 days after the cessation.

Moreover, your license from a particular copyright holder is
reinstated permanently if the copyright holder notifies you of the
violation by some reasonable means, this is the first time you have
received notice of violation of this License (for any work) from
that copyright holder, and you cure the violation prior to 30 days
after your receipt of the notice.

Termination of your rights under this section does not terminate
the licenses of parties who have received copies or rights from you
under this License.  If your rights have been terminated and not
permanently reinstated, receipt of a copy of some or all of the
same material does not give you any rights to use it.

@item
FUTURE REVISIONS OF THIS LICENSE

The Free Software Foundation may publish new, revised versions of
the GNU Free Documentation License from time to time.  Such new
versions will be similar in spirit to the present version, but may
differ in detail to address new problems or concerns.  See
@uref{http://www.gnu.org/copyleft/}.

Each version of the License is given a distinguishing version
number.  If the Document specifies that a particular numbered
version of this License ``or any later version'' applies to it, you
have the option of following the terms and conditions either of
that specified version or of any later version that has been
published (not as a draft) by the Free Software Foundation.  If
the Document does not specify a version number of this License,
you may choose any version ever published (not as a draft) by the
Free Software Foundation.  If the Document specifies that a proxy
can decide which future versions of this License can be used, that
proxy's public statement of acceptance of a version permanently
authorizes you to choose that version for the Document.

@item
RELICENSING

``Massive Multiauthor Collaboration Site'' (or ``MMC Site'') means any
World Wide Web server that publishes copyrightable works and also
provides prominent facilities for anybody to edit those works.
A public wiki that anybody can edit is an example of such
a server.  A ``Massive Multiauthor Collaboration'' (or ``MMC'')
contained in the site means any set of copyrightable works thus
published on the MMC site.

``CC-BY-SA'' means the Creative Commons Attribution-Share Alike 3.0
license published by Creative Commons Corporation,
a not-for-profit corporation with a principal place of business in
San Francisco, California, as well as future copyleft versions of
that license published by that same organization.

``Incorporate'' means to publish or republish a Document, in whole
or in part, as part of another Document.

An MMC is ``eligible for relicensing'' if it is licensed under this
License, and if all works that were first published under this
License somewhere other than this MMC, and subsequently
incorporated in whole or in part into the MMC, (1) had no cover
texts or invariant sections, and (2) were thus incorporated prior
to November 1, 2008.

The operator of an MMC Site may republish an MMC contained in the
site under CC-BY-SA on the same site at any time before August 1,
2009, provided the MMC is eligible for relicensing.
@end enumerate

@page

@anchor{ADDENDUM How to use this License for your documents}
@appendixsec ADDENDUM: How to use this License for your documents

To use this License in a document you have written, include a copy of
the License in the document and put the following copyright and
license notices just after the title page:

@example
Copyright (C)  YEAR  YOUR NAME.
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.3
or any later version published by the Free Software Foundation;
with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
Texts.  A copy of the license is included in the section entitled ``GNU
Free Documentation License''.
@end example

If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts,
replace the ``with@dots{}Texts.''@tie{}line with this:

@example
with the Invariant Sections being LIST THEIR TITLES, with
the Front-Cover Texts being LIST, and with the Back-Cover Texts
being LIST.
@end example

If you have Invariant Sections without Cover Texts, or some other
combination of the three, merge those two alternatives to suit the
situation.

If your document contains nontrivial examples of program code, we
recommend releasing these examples in parallel under your choice of
free software license, such as the GNU General Public License, to
permit their use in free software.

@node Main Index
@chapter Main Index

@printindex cp

@node Key Index
@chapter Key Index

@printindex ky

@node Command and Function Index
@chapter Command and Function Index

@printindex fn

@node Variable Index
@chapter Variable Index

This is not a complete index of variables and faces, only the ones
that are mentioned in the manual.  For a more complete list, use
@kbd{M-x org-customize} and then click yourself through the tree.

@printindex vr

@bye