Linux distributions are versions of the operating system which are developed by different groups. Built with architecture similar to Unix, programs and desktops available in one distro are often available in others.
Well updated and widely distributed distros typically have support forums. Users may ask questions, and search for previous questions which have been answered.
Most of the kernel and supporting packages are free and open source software. Linux distributions have taken a wide variety of forms, from fully featured desktop and server operating systems to minimal environments for use on floppy disk.
One can distinguish between commercially backed distributions, such as Fedora (Red Hat), openSUSE (Novell), Ubuntu (Canonical Ltd.), and Mandriva Linux (Mandriva), and entirely community-driven distributions, such as Debian and Gentoo, though there are other distributions that are driven neither by a corporation nor a community, perhaps most famously Slackware.
Many distributions have large international networks of testers and support personal.