unrar (or unrar-free in some Linux distributions) is a free software version of the non-free unrar utility that exists on many GNU/Linux systems today. It uses the GPL'd UniquE RAR Library by Christian Scheurer and Johannes Winkelmann. This program is a simple command-line front-end to this library, and can list and extract RAR archives. It does not rival the non-free unrar in terms of features, but special care has been taken to ensure it meets most user's needs and it is hoped that GUI archivers such as GNOME's file-roller and KDE's ark will use this utility as a back-end. It does not support the RAR3 format.