BarCamp is an international network of user generated conferences (or unconferences) - open, participatory workshop-events, whose content is provided by participants. The first BarCamps focused on early-stage web applications, and related open source technologies, social protocols, and open data formats. The format has also been used for a variety of other topics, including public transit, health care, and political organizing.

The name "BarCamp" is a playful allusion to the event's origins, with reference to the hacker slang term, foobar: BarCamp arose as a spin-off of Foo Camp, an annual invitation-only participant driven conference hosted by open source publishing luminary Tim O'Reilly.

The idea is that participants help to make the event into a success. The best contribution you can make is give a presentation on a topic that you have knowledge, experiences or ideas about. You don't need to request a timeslot beforehand or supply your slides. Just bring a laptop or USB stick (or use Slideshare) and pick a presentation slot in the morning. If you already have an idea for a presentation, it is nice to mention this during registration. In this way, participants can get a feeling of what the day will look like.

Other ways of contributing is helping with registration, timekeeping, serving coffee or cleaning up. The general principle is that everyone is available to do small things, nobody is a "customer".

To keep a barcamp free, it is important to offer good exposure to your sponsors. They know that if you honor them, the participants will check out their website and services. When there are no reserved presentation slots for sponsor's commercial messages, the sponsor gains more sympathy from the participants.