Ubuntu (pronounced /u'bun.tu/, or "oo-boon-too"), is a Debian-derived computer operating system based on GNU/Linux. Ubuntu's goals include providing an up-to-date, stable operating system for the average user, with a strong focus on usability and ease-of-installation. Ubuntu has been selected by readers of desktoplinux.com as the most popular Linux distribution for the desktop, claiming approximately 30% of their desktop installations in both 2006 and 2007.

Ubuntu is composed of multiple software packages distributed under free software /open source licenses, especially the GNU General Public License (GNU GPL) so that users are free to run, copy, distribute, study, change and improve the software. Ubuntu is sponsored by the company Canonical Ltd., owned by South African entrepreneur Mark Shuttleworth. Instead of selling Ubuntu for profit, Canonical creates revenue by selling technical support. By keeping Ubuntu free software and open source, Canonical is able to take advantage of the talents of outside developers in Ubuntu's constituent components without developing the entire operating system itself (which is based primarily on current Linux kernels).

Canonical endorses and provides support for four additional Ubuntu-like operating systems: Kubuntu, Xubuntu, Edubuntu (a subproject and add-on for Ubuntu, designed for school environments and home users), and Ubuntu JeOS (pronounced "Juice", a stripped-down version of Ubuntu optimized for virtual appliances).

Canonical releases new versions of Ubuntu every six months and supports Ubuntu for eighteen months by providing security fixes, patches to critical bugs and minor updates to programs. LTS (Long Term Support) versions, which are released every two years, are supported for three years on the desktop and five years for servers. The current version of Ubuntu, 9.04, was released on April 23, 2009, and the upcoming version, Karmic Koala, is expected to be released on 29 October 2009.

History and development process

Ubuntu was initially forked from the Debian project's code base. The aim was to release a new version of Ubuntu every six months, resulting in a more frequently updated system. Ubuntu's first release was on October 20, 2004. The name Ubuntu, pronounced IPA2: uːˈbuːntuː in English, comes from the Zulu word "ubuntu" (1), translated as "humanity to others", describing the ubuntu philosophy: "I am what I am because of who we all are", a positive aspect of community.

New releases of Ubuntu coincide a month after GNOME releases. In contrast to previous general-purpose forks of Debian — such as MEPIS, Xandros, Linspire, Progeny and Libranet, many of which relied on proprietary and closed source add-ons as part of their business model — Ubuntu has stayed closer to Debian's philosophy and uses free (libre) software, making an exception only for some proprietary hardware drivers.