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, Flash, and RSS. It provides code examples of AJAX and discusses frameworks like ASP.NET AJAX. The document also addresses economic benefits to marketing and communication through Web 2.0 applications, and envisions further growth and new technologies for the future web.