Chances are that you have heard of Wikis by now -- they seem to be popping up everywhere. For example, The most famous wiki is called Wikipedia, a massive online encyclopedia. Wikipedia has become so large (more than a million articles) that you run across it all the time in Google. It is so popular that it is now one of the Top 100 web sites in the world!

Despite their popularity, Wikis seem very strange to many people. Where does all the information come from? Is it reliable? What stops people from vandalizing a wiki until it dies? These questions and many others will be answered as we dive into the world of wikis...
Wikis are growing because, at their core, they are about as simple as can be. That simplicity means that people find them easy to use, just like e-mail and blogs. Like e-mail and blogs, wikis also perform a very useful service in a simple way. A wiki allows a group of people to enter and communally edit bits of text. These bits of text can be viewed and edited by anyone who visits the wiki.

That's it. What it means is that, when you come to a wiki, you are able to read what the wiki's community has written. By clicking an "edit" button on an article, you are able to edit the article's text. You can add or change anything you like in the article you are reading.