Anyone can put any information on the internet
You must make sure that the information you are getting is accurate.
You must make sure that the website you are using is a dependable resource.
Who is the author?
What are the author's credentials, experience, education?
Is the author an expert in the subject area you are researching?
Organization - What is the reputation of the organization behind the website?
Look for 'About Us', 'FAQs', or Author Profile on website. (These are usually available from the home page. Truncate the url to get to the home page.)
Where did the author get the information?
Are there typos or spelling errors?
Does the information seem accurate?
Does the website provide information that helps you with your research?
Are you able to find relevant information easily on the website?
Does the website seem to be trying to persuade you to a particular opinion?
.com - Is the website trying to sell you something? Are there a lot of advertisements?
Does the author cite the sources for his information on the website?
Does the information come from dependable sources?
What links are provided by the author? Do the links work? Are they useful?