Until a couple of years ago, my only experience with a wiki was Wikipedia. Funny thing is, I was always cautioned to stay away from Wikipedia. It tends to get a bad reputation with regard to reliability and accuracy of information, which is understandable, seeing as how anyone can edit its pages. You see, wikis provide a quick way for people or groups of people to share what they know about a topic. The members of this group can edit and add material to make the site better. It's basically a web page that a group shares.
While wikis can be a bit scary when students are searching for information, they are ideal for students to use when constructing information. A great example of this is our very own advocacy wikis. They afford group work even when the group cannot physically meet. Wikis also allow you to edit the work of peers. The history feature allows you to monitor the edits made by each group member too.
The benefit of using wikis with students is best expressed by Will Richardson, "In using wikis, students are not only learning how to publish content; they are also learning how to develop and use all sorts of collaborative skills, negotiating with others to agree on correctness, meaning, relevance and more. In essence, students begin to teach each other."