The document defines and discusses the concept of Web 2.0. It notes that Web 2.0 emerged in 2003 with the rise of applications like blogs and social networks that allowed users to become more active participants rather than passive subjects. Web 2.0 refers to web applications that enable users to share information online. It also discusses how Web 2.0 transformed the internet by allowing anyone to create their own space and share content, which was a major change from the past when the internet did not support as much interactivity and sharing between users.