The document discusses the evolution of the web from Web 1.0 to Web 2.0 and the concept of Library 2.0. It describes how Web 2.0 enables user participation and collaboration through social software. Library 2.0 aims to harness collective intelligence and user participation by implementing Web 2.0 technologies and principles in libraries, such as wikis, user tagging, and user-driven services. The document provides examples of libraries that have implemented Library 2.0 ideas and discusses practical considerations for libraries looking to adopt Web 2.0 approaches.