What the heck is a wiki? A wiki allows users to read, post and change web pages.

The best explanation is this video.

The most famous wiki is probably Wikipedia, which is now the largest encyclopedia, with pages on many different subjects. Some pages include: Onalaska, Nederland, Texas City and Wharton.

You can create your own wiki.  Some simple, free sites to establish your own wikis include PBWiki, Wikispaces and Wetpaint.