Linux Mint's purpose is to produce an elegant, up-to-date, and comfortable GNU/Linux desktop based on Ubuntu. Linux Mint 16 is based on Ubuntu 13.10, Linux 3.11, Cinnamon 2.0, and MATE 1.6.
Ubuntu features a fast and easy install, a tight selection of excellent applications installed by default, and every other package you can imagine available with a few clicks.
Mageia is a fork of Mandriva Linux formed in September 2010 by former Mandriva employees and contributors. Features KDE 4.11, GNOME 3.10, and XFCE 4.10.
The Debian Project is an association of individuals who have made common cause to create a free operating system. Debian 7.4 features KDE 4.8.4, GNOME 3.4, and Linux 3.2.
Promoting the use of Linux everywhere, this project provides free, easy access to the world's most usable Linux distribution, openSUSE. Features Gnome 3.10, KDE 4.11, Linux 3.11.
Fedora is a Red Hat sponsored and community-supported project. It is also a proving ground for new technology that may eventually make its way into Red Hat products.