The Web and its tools of orientation: how better to understand the information available on the Internet by the analysis of references? In the incessant and chaotic frenzy of the Internet, suitable tools and techniques are urgently required for use by information professionals. The Internet has become a leading venue for communication among researchers, both scientists and other scholars. The role of mediation for these professionals has never been so important, owing to the actual deficiencies of the search systems on the Internet. This article expounds the tools that are now available for the identification and evaluation of Internet sources. After a discussion of the techniques of discrimination and cartography, a method of constructing a navigation map of the Web by the analysis of citations is explained.