Since information on the web can be created by anyone and because many sites do not go through a formal screening process, it is important to evaluate the websites you use for credibility, and authority, and accuracy. It is not always easy to determine if information on the World Wide Web is credible. The following criteria can help you to determine the quality of the information you find on the web.
Accuracy: The reliability, truthfulness, and correctness of the content
Objectivity: The reason the information exists
Coverage & Relevancy: The importance of the information for your needs
For more tips see:
The Georgetown University Library [Guide] Evaluating Internet Resources -
Wikipedia is a great tool for a summary of a topic. Wikipedia content is constantly revised, and entries vary in quality. Some of the content is excellent, some is questionable.
Many educators frown on the use of Wikipedia. Why?
How can you use Wikipedia in a way that benefits your research process?