As mentioned on FOSDEM's about page,
FOSDEM is a free and non-commercial event organized by the community for the community. The goal is to provide Free Software and Open Source developers and communities a place to meet to:
- get in touch with other developers and projects;
- be informed about the latest developments in the Free Software and Open Source world;
- attend interesting talks and presentations held in large conference rooms by Free Software and Open Source project leaders and committers on various topics; and
- to promote the development and the benefits of Free Software and Open Source solutions.
Participation and attendance is totally free, though the organization gratefully accepts donationals and sponsorships.