Web Source Evaluation

Why should I believe this person? The author of the source should be clearly identifiable. The author's credentials or authority (expertise) should also be available somewhere on the website. Sources for which you cannot determine authority should not be used for essential support of your thesis.
Official Website
Is this a reliable website? Sources found on an official website (i.e., Nike, Christian Reformed Church, World Trade Organization) tend to be more reliable than sources taken from web sites created by individuals. The source may still be biased or one-sided, but it tends to be edited for accuracy if on an official website.
Is it the real thing? Internet documents can easily be modified. Also, sources that have been re-typed (transcribed) from a paper original (i.e., a diary) may contain errors. Trustworthy web documents will include a citation to the original document. When possible, always verify the accuracy of a web document by either finding the original paper source or comparing it to the same document on another website.
How biased is it? Nothing is written in a vacuum. Every author includes personal opinions and biases and writes for a particular audience. So, identifying a bias is not grounds for ignoring a web source. Understand the author's perspective and the severity of the bias and use the document accordingly.
How old is it? Is the creation date clearly listed on the page? Is there an updated date? How old is the information?
For whom is it written? Closely related to objectivity, is the author's audience for the web document. Is the page intended to be a lighthearted look at the topic? Is it intended for a scholarly audience? For high school age students? The general public? This will determine the relative weight you can put on the content.
How complete is the information? Determine if the author attempts a complete analysis. Are all sides of the issue represented? Does the analysis provide depth? This criteria is closely aligned with "Objectivity" and "Audience." Ask yourself if there might be a better source for the information represented on the web page.