http://fedoraproject.org/wiki/Overview
An operating system, a set of projects, and a mindset.
What is Fedora? Fedora is a Linux-based operating system that showcases the latest in free and open source software. Fedora is always free for anyone to use, modify, and distribute. It is built by people across the globe who work together as a community: the Fedora Project. The Fedora Project is open and anyone is welcome to join. The Fedora Project is out front for you, leading the advancement of free, open software and content.
The operating system is Fedora. It comes out twice a year. It's completely free, and we're committed to keeping it that way. It's the best combination of robust and latest software that exists in the free software world.
The mindset is doing the right thing. To us, that means providing free and open software and content, at no cost, freely usable, modifiable, redistributable, and unencumbered by software patents.