A.. "wiki" or "wikki" is a document that is collectively created and maintained. Anyone can edit it. This feature evokes a sense of responsibility and seriousness among most Internet surfers (sometimes this is too much for people). It's a great means to utilize the Internet community, allowing users to build something useful for everyone.

Surprisingly, there were few problems with people abusing wiki, but more often these days, people are password protecting ones directly on the Internet due to spammers trying to up their pageranks in search engines. Because modifications are both easy and expected, there's no challenge to "breaking" and defacing a page. And that same ease of modification allows anyone to rollback a modification if someone does deface a page.

There is a lot of transparency in wiki. It's possible to learn implicitly from the pages what you need to know to create WikiWords. NetAddresses? are or can be made to be short, with each piece conveying clear information that people can use (e.g. http://c2.com/cgi/wiki?CopyRight). Most decisions and actions are taken within the wiki, where no one has special power (outside the wiki, some people have a password or physical access to a machine, until someone develops RobustWiki).

Wikis yield the most fruit when they have a specific purpose & are maintained by interested parties in the purpose. They are also extremely easy for new people on the web to edit.

Wikis were originally created in 1995 by Oregon programmer Ward Cunningham. Cunningham named the term wiki for the "wiki wiki" or "quick" shuttle buses at Honolulu Airport.

Historical Note. The first ever wiki site was created for the Portland Pattern Repository in 1995. That site now hosts tens of thousands of pages.

http://c2.com/cgi/wiki?WelcomeVisitors

http://c2.com/cgi/wiki?WikiHistory

http://c2.com/cgi/wiki?WikiDesignPrinciples

More on wikis at WikiPedia:Wiki.