The document discusses opportunities and threats related to social networks. It notes that 70% of web users visit social networks, with major platforms like Facebook, MySpace, Twitter, and LinkedIn having hundreds of millions of users each. However, it also outlines privacy and security risks like identity theft, malware propagation, and corporate data leakage that social networks can enable if not used carefully. The document provides an overview of these risks and threats as well as recommendations for safe social network usage.