Open content, coined by analogy with open source, describes any kind of creative work (for example, articles, pictures, audio, video, etc.) that is published under a non-restrictive copyright license and format that explicitly allows the copying of the information. (An example is the GNU Free Documentation License, which is used by Wikipedia and Nupedia.) But "open content" also describes content that can be modified by anyone. Of course, this is not without prior review by other participating parties--but there is no closed group like a commercial encyclopedia publisher which is responsible for all the editing.