The important part of wikis—what makes them different from any other type of website—is collaborative editing by the users. Think about that for a moment: the ability for the users of a wiki to collaboratively edit it. If you can read it, you can edit it. It seems simple at first, yet profoundly powerful in practice—and it is what both Wikipedia and WikiLeaks have in common.
That's what we're going to explore: the benefits a wiki can provide to a business, the sort of problems it can solve, and what sort of options you have for setting up a wiki for yourself. It's a lot to cover, so let's keep things moving. (Source)