# Yubico Universal 2nd Factor C Library

The latest version of this documentation can be found on-line at https://github.com/Yubico/libu2f-host.

## Yubico Universal 2nd Factor C Library

This is a C library that implements the host-side of the U2F protocol. More precisely, it provides an API for applications that wishes to talk to a U2F device and perform the U2F Register and U2F Authenticate operations.