A wiki is a website that allows the visitors themselves to easily add, remove, and otherwise edit and change some available content, sometimes without the need for registration

A wiki enables documents to be written very collaboratively in a simple markup language using a browser. A single page in a wiki is referred to as a "wiki page", while the entire body of pages, which are usually highly interconnected via hyperlinks, is "the wiki"; in effect, a wiki is actually a very simple, easy-to-use user-maintained database for searching or even creating information.