The document provides an overview of three social networking sites: YouTube, Flickr, and MySpace, detailing their functions and how to use them. YouTube is primarily for sharing videos, Flickr focuses on photo sharing and tagging, while MySpace allows users to create personalized pages and connect with others, particularly musicians. It also addresses user-generated content, potential controversies, privacy issues, and offers further reading resources for those interested in social networks and their applications in libraries.