Wikipedia is a great source of free information. Unfortunately, that information is provided by the site's users, not by any academic or editorial staff. Does that mean that the information on the Wikipedia site is less accurate than you'd find in a traditional encyclopedia? Or is Wikipedia a good source when you're assembling research for a report or project?
Where Wikipedia Gets Its Information
To the casual user, Wikipedia looks and works like a traditional encyclopedia, albeit one based on the Internet. Unlike a traditional encyclopedia, however, Wikipedia's content is created solely by the site's users; no authorial or editorial staff are writing and editing articlesor checking those articles for accuracy.
That's right, anyone can write or edit Wikipedia articles; you don't have to be a professional or an academic to contribute articles to the site. And no formal fact-checking apparatus is in place; instead, Wikipedia relies on its community of users to edit, correct, and police the information that other users create. Once one user writes an article, other users can edit and add to that article. In this fashion, information is vetted for both accuracy and appropriateness.
That's not to say that there aren't any rules as to what is and isn't acceptable. Indeed, Wikipedia offers some broad editorial guidelines to all its writers/editors. These guidelines state that to be included in the Wikipedia, an article must be about a topic that is encyclopedic and worthy of inclusion. In this way, spurious topics that are not "notable," in Wikipedia's words, are excluded.
An entry must also expose knowledge that is already established or recognized; it cannot present independent works or new information not present elsewhere.
Finally, entries should not reflect bias or take a side in a debate; all opinions and viewpoints should receive equal coverage within an article.
These guidelines are only as good as they're followed, of course, because Wikipedia does not have a staff to actively enforce these guidelines. Instead, Wikipedia relies on its users to police new and updated articles, and to make changes to or delete those articles that don't meet the guidelines.