This document discusses Web 2.0 concepts, technologies, and applications. It covers the social and collaborative aspects of Web 2.0, including wikis, blogs, social bookmarking, social networks, and browser-based applications. Technically, Web 2.0 relies on AJAX, which allows asynchronous JavaScript and XML for faster interaction. Economically, Web 2.0 benefits marketing by engaging customers and facilitating internal communication. The future of the web is expected to involve more user-generated content and new frameworks like the Semantic Web.