The Scratch Wiki is a collaboratively-written wiki available for free that provides information about the Scratch programming language and its website, history, and phenomena surrounding it.The wiki is supported by the Scratch Team, but is primarily written by Scratchers. The Scratch Wiki is a popular source of information for scripts and tutorials, and it continues to grow as Scratchers use it as their primary source of information. This could also include advanced articles for Scratchers around the world to build, share, and see.

Source : http://wiki.scratch.mit.edu/wiki/Scratch_Wiki