Before using any information you should critically evaluate source, especially if it is from a website.  

Ask yourself:

Currency

• How current is the information? Does currency matter for your topic?

Reliability

• Where did the information come from? Are there citations?
• Is it sponsored by an organization that might have a bias? How can you tell?
• Is the data sound? Could another conclusion be made based on the data? Is there data missing?

Authority

• Who wrote or presented the information? Is this person trustworthy/an expert? How do you know?
• Does the writer have a degree in the subject? What are his or her affiliations (where does the author work)? What do others in the field think about this person?
• What else has this person written about the topic? Is he or she an expert?

Purpose

• For what purpose is this information being made available? Does it match your own research purposes?

Be sure to ask a librarian if you're still unsure if a website or article is appropriate for your research.