This document discusses the evolution of Web 2.0 and social media platforms like YouTube. It provides background on improvements made to Web 2.0 since its launch, examples of social network types, and both the advantages and disadvantages of Web 2.0 technologies. The document also examines the impact of YouTube since its introduction, how it works, how advertising is used, and both the benefits and risks of the video platform. Finally, it outlines YouTube's target audience and categories, and how users can sign up.