Revision with unchanged content. At first sight, browsing the World Wide Web is a fairly intuitive and simple activity, but it turns out that users often experience difficulties in finding the information and services that they are looking for - or in returning to items that they have visited before. In order to improve the current design of Web sites and Web browsers, or to provide users with personalized interfaces, one needs to know how users interact with the Web. Although theoretical models and empirical data exist, the knowledge that they provide is limited and scattered. In this book, we integrate current insights and extend this body of knowledge with a number of user studies. Several methods are presented for obtaining, clearing, analyzing and visualizing Web usage data. Various aspects of user navigation styles are discussed. Particular attention is given to the issue why, when and how often users return to Web pages, and how browsers can support this more effectively. An important observation is that the Web has evolved from a hypermedia system to a hybrid between hypermedia and interactive applications. This book targets researchers and professionals who want to better understand and support the users that visit their Web sites or that make use of their applications and tools.