Linux
GuixSD is an advanced distribution of the GNU operating system developed by the GNU Project—which respects the freedom of computer users.
Aryalinux is a GNU/Linux Operating System built from the source code of the various component packages it consists of
Elementary OS is a well-polished desktop Linux distribution based on Ubuntu, known as the most beautiful Linux distribution
CentOS 6 is a community-supported distribution derived from sources freely provided to the public by Red Hat for Red Hat Enterprise Linux.
Pinguy OS is an Ubuntu-based distribution for Linux novices. It features a large number of user-friendly enhancements, out-of-the-box support for multimedia codecs and browser plug-ins
Redcore Linux shares the same idea as his defunct ancestor, Kogaion Linux: to bring the power of Gentoo Linux to the masses.
Bodhi Linux is a desktop-based Ubuntu-based distribution that features an elegant and lightweight Enlightenment window manager.
SliTaz GNU/Linux is a free operating system working completely in memory from removable media such as a CD-ROM or USB key.
Raspbian is a free operating system based on Debian GNU / Linux, which is optimized for Raspberry Pi hardware (armhf processor architecture)