This document discusses the concept of Web 2.0 and how it represents a shift from the web being purely informational to having a strong social component. It outlines some key technologies and applications that emerged with Web 2.0 like blogs, wikis, social networking sites, and user-generated content. It also discusses how Web 2.0 is distinguished from Web 1.0 by significant advances in technology, applications, and scale due to factors like increased broadband access and more powerful/affordable computers.