CCC can refer to variously as Chaos Communication Congress, an the organisation and legal entity Chaos Computer Club.
The Chaos Communication Congress (CCC),is an annual conference organized by the Chaos Computer Club. The congress features a variety of lectures and workshops on technical and political issues related to Security, Cryptography, Privacy and online Freedom of Speech - wikpedia 
Hackers all over the world are organizing events to bring the congress closer to home. Congress Everywhere: allows those unable to attend the Congress in Hamburg to celebrate their own Hackcenter experience, watch the streams, participate via twitter or chats, drink Tschunk, cook and have a good time.
CCC-TV, offers a wide variety of video and audio material distributed by the Chaos Computer Club provided in native formats (usually MPEG and/or Vorbis families) for online viewing. Older, archived recordings might require proprietary players. The media files on this site can also be downloaded for offline consumption - media.ccc.de
The Chaos Communication Camp is an international meeting of hackers that takes place every four years, organized by the Chaos Computer Club (CCC).