A demoparty is an event that gathers demosceners and other computer enthusiasts to partake in competitions of demos (short audio-visual presentations of computer art). A typical demoparty is a non-stop event spanning a weekend, providing the visitors a lot of time to socialize. The competing works, at least those in the most important competitions, are usually shown at night, using a video projector and big loudspeakers. The most important competition is usually the demo compo.
The visitors of a demoparty often bring their own computers to compete and show off their works. To this end, most parties provide a large hall with tables, electricity and usually a local area network connected to the Internet. In this respect, many demoparties resemble LAN parties, and many of the largest events also gather gamers and other computer enthusiasts in addition to demosceners. A major difference between a real demoparty and a LAN party is that demosceners typically spend more time socializing (often outside the actual party hall) than in front of their computers.
Large parties have often tried to come up with alternative terms to describe the concept to the general public. While the events have always been known as "demoparties", "copyparties" or just "parties" by the subculture itself, they are often referred to as "computer conferences", "computer fairs", "computer festivals", "computer art festivals", "youngsters' computer events" or even "geek gatherings" or "nerd festivals" by the mass media and the general public.
Demoscene events are most frequent in continental Europe, with around fifty parties every year—in comparison, the United States only has two or three each year. Most events are local, gathering demomakers mostly from a single country, while the largest international parties (such as Breakpoint and Assembly) attract visitors from all over the globe.