From Fedora Project Wiki
FUDCon is the Fedora Users and Developers Conference, a major free software event held in various regions around the world, usually annually per region. FUDCon is a combination of sessions, talks, workshops, and hackfests in which contributors work on specific initiatives. Topics include infrastructure, feature development, community building, general management and governance, marketing, testing and QA, packaging, etc.
FUDCon is always free to attend for anyone in the world.