Fedora is an open source operating system using ''RPM-based'' -- linux distributions that use a tool to automate the process of installing, upgrading, configuring and removing software packages from a computer --, built on top of the Linux kernel. It is developed and maintained by a community-support known as the Fedora Project which is sponsored by Red Hat. The Fedora Project's mission is "To lead the advancement of free and open source software and content as a collaborative community." Fedora’s main aim is to be a leader in the use and distribution on software designed as open source. Fedora has a release every six months and a maintenance period of about thirteen months for each of its releases. Fedora 12 was released November 11, 2009 and Fedora 13 has an expected release date of May 18, 2010.