From Wikipedia:

A Wiki or wiki (pronounced wɪki, wiki or viki) is a website that allows users to add content, as on an Internet forum, but also allows anyone to edit the content. "Wiki" also refers to the collaborative software used to create such a website (see Wiki software).

Wiki (with an upper case 'W') and WikiWikiWeb are both used to refer specifically to the Portland Pattern Repository, the first-ever wiki. This usage's proponents suggest a lower-case 'w' for wikis in general. The name was based on the Hawaiian term wiki wiki, meaning "quick" or "super-fast". Sometimes wikiwiki or WikiWiki are used instead of wiki.

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