A BarCamp is an ad-hoc gathering born from the desire for people to share and learn in an open environment. It is an intense event with discussions, demos, and interaction from participants. If you want to attend, you are encouraged to give a presentation or a demo of some kind. Have a look at wikipedia for more information.
If you have questions or experience problems, please report them to the BarCamp support forum. For issues related to this wiki, please see the PBWiki Support Forum.