There are currently 1,597 articles on the Scratch Wiki.
On December 6, 2008, LukeTek created the Scratch Programming Wiki — it was a normal wiki created solely by himself, and the Scratch Team were not involved. He handed the wiki over to JuiceyBox, who later gave the wiki to Lucario621. He advertised the wiki in the Miscellaneous forum, and many people helped contribute — however, the articles were of projects, users, and the like. The wiki was cleaned up, but by then people had lost interest. A few people stayed behind though, and the wiki steadily grew.
Eventually, the Scratch Team saw the wiki. They liked it and wanted to advertise it on the Scratch Website, but they had some concerns — it had advertisements, it wasn't in a scratch.mit.edu domain, and there was no way to tell if a user on the wiki was the same user on Scratch. To solve these problems, andresmh, JSO and Lucario621 created a new Scratch Wiki, hosted on the Scratch servers. All three problems were solved — there were no advertisements, it was on a scratch.mit.edu domain, and there was a way to ensure that users on the wiki were the same users on Scratch: Account creation was locked; people would request for an account instead.
What the Wiki is
This is a wiki which currently has 1,597 articles, and all have something to do with Scratch. The wiki is a very useful source of information about anything Scratch-related. It has a dedicated, core team of editors, as well as other, no less talented, editors. The wiki stays up to date with everything that is happening with the world of Scratch.
Many Scratchers go to the wiki first when they want information or help. The wiki continues to grow, and more and more users are using it as their primary source of information.