When first visiting a web site, it's often difficult to determine what topics are covered and how in-depth these topics are discussed. You may find yourself looking at a web site that deals very generally with many topics or very specifically about one topic- or something in between. The main thing is to determine if the Web site deals with your topic in terms that you can understand and provides information that you haven't already found, i.e. is unique and not redundant.
Since the Web as we know it has only been around since 1994 it is important to consider whether your topic will even be addressed on a web page, or how comprehensive a web page on your topic might be.
