The public information available on the Web today is larger than information distributed on any other media. The raw nature of Web content, the unpredictable remote changes that can affect it, the wide variety of formats concerned, and the growth in data-driven websites make the preservation of this material a challenging task, requiring specific monitoring, collecting and preserving strategies, procedures and tools. Julien MasanA]s, Director of the European Archive, has assembled contributions from computer scientists and librarians that altogether encompass the complete range of tools, tasks and processes needed to successfully preserve the cultural heritage of the Web. His book serves as a standard introduction for everyone involved in keeping alive the immense amount of online information, and it covers issues related to building, using and preserving Web archives both from the computer scientist and librarian viewpoints. Practitioners will find in this book a state-of-the-art overview of methods, tools and standards they need for their activities. Researchers as well as advanced students in computer science will use it as an introduction to this new field with a hopefully stimulating review of open issues where future work is needed.