Why use a wiki, when anyone can change or delete anything there? What's to prevent someone from going berserk and wiping the whole site, or secretly changing the meaning of what people say, or clogging everything up with spam?

Most community web sites rely on technology to restrict the actions of community members. Elaborate schemes have been designed to moderate postings (such as Slashdot [1] and Kuroshin [2]) or to establish a trust metric for community members to rate each other (such as Epinions [3]).

There are several problems with this:

Wikis work because they rely on the community, rather than technology, to police themselves. If someone comes along and deletes text or posts spam, someone else can just as easily fix the problem. Since an open environment encourages participation and a strong sense of community, the ratio of fixers to breakers tends to be very high, so the wiki stays stable.

There are technological protections, too -- they're just less obtrusive than having to "log in" or "rate" something. Most wikis store old versions of each page for at least a short period of time, allowing damage to be easily recovered. Many wikis provide a means to limit how quickly someone may edit a large number of pages. Most wikis also provide a means to lock out particularly abusive visitors without disturbing other visitors. WikkiTikkiTavi has all of these features.

In short, wikis work because of the community. For more background on this, see the following excellent pages: MeatBall:SoftSecurity?, MeatBall:CommunitySolution?, MeatBall:CommunityExpectation?, Wiki:WhyWikiWorks. See also Wiki:WikiMindWipe?, Wiki:WikiMindWipeDiscussion?, and MeatBall:WikiMindWipeDiscussion? for the story of several wiki participants who left -- taking all of their contributions with them.

Will wiki work with a small user base?