Wikipedia is an online encyclopedia created by the collective, and anonymous, efforts of hundreds or thousands of people. Some of those people are experts in the fields they have contributed in, others are not. For more information on Wikipedia, including discussions of its value and danger, check out the Pathfinder for Wikipedia.
What You Can Get From a Wikipedia Article
Wikipedia is often a good introduction to a topic. But it's just an introduction. And don't be surprised if your instructor will not let you include Wikipedia as a reference in your paper. Journal articles, books, and other resources are much more important. Wikipedia is a good start, but it's only a start.
Other Things You Can Do
Resources on Researching