Wikipedia Rocks!

If you don't know about Wikipedia, take a moment to check it out. This vast online encyclopedia with extensive cross-linking of references is an example of an "open source" project. Open source implies decentralized creation of content (in this case, the encyclopedia entries) by many people all over the world, and freely distributed without restriction or copyright. In fact, the proponents of open source projects use the term "copyleft" to describe how such material should be shared. Probably the most recognizable example of a project like this is Linux, the open source operating system.