A collaboration website allows many people to work on the same project.
The project will typically be of interest to all of the collaborators, although there may be areas that are of more interest than others. It is a way of getting people with certain knowledge together. For example, the collaboration project could be about the place you live and may include pages such as history, attractions, shops, schools and libraries.
Possibly the most famous collaboration web site is WikiPedia, which is an online encyclopedia that is constantly being updated by people around that world who are interested in adding their knowledge to projects that interest them.
These web sites allow for multimedia content to be added to them, allowing people to upload photographs, sounds and video.