A wiki is a collaborative community website that allows users to easily create pages and edit pages others have created. You can start a new wiki for free by visiting Wikia's CreateWiki page.
It is very easy to edit a wiki. With Wikia's rich text editor, you don't need even to learn any wiki markup. Every edit made to a Wikia is stored for as long as the wiki exists. This means you can easily check which edits have been made. You can also easily remove bad edits as you can change back to an older version of the page.