Fedora is a Linux-based operating system, a collection of software that makes your computer run. You can use Fedora in addition to, or instead of, other operating systems such as Microsoft Windows™ or Mac OS X™. The Fedora operating system is completely free of cost for you to enjoy and share.

The Fedora Project is the name of a worldwide community of people who love, use, and build free software. We want to lead in the creation and spread of free code and content by working together as a community. Fedora is sponsored by Red Hat, the world's most trusted provider of open source technology. Red Hat invests in Fedora to encourage collaboration and incubate innovative new free software technologies.

http://www.fedoraproject.org