According to Ward Cunningham, the inventor of the very first wiki (WikiWikiWeb), a wiki is "The simplest online database that could possibly work."
A wiki engine is a piece of software that enables the creation of a wiki site. A wiki site allows users to create and modify pages on the fly using their web browser, and a basic markup syntax.
The wiki platform allows collaboration and group communication quite unlike anything else.
The diagram to the right shows an example of how a wiki is edited by many users over a period of time, resulting in what you see presently.
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