Abstract : The Web is a huge source of information, and one of the main problems facing users is finding documents which correspond to their requirements. Apart from the problem of thematic relevance, the documents retrieved by search engines do not always meet the users' expectations. The document may be too general, or conversely too specialized, or of a different type from what the user is looking for, and so forth. We think that adding metadata to pages can considerably improve the process of searching for information on the Web. This article presents a possible typology for Web sites and pages, as well as a method for propagating metadata values, based on the study of the Web graph and more specifi- cally the method of cocitation in this graph.