The document discusses the history and evolution of social networks. It notes that SixDegrees, launched in 1997, was one of the first recognizable social networking sites, allowing users to create profiles and connect with friends. While precursors to social networks existed, SixDegrees was the first to combine functions like profiles and friends lists into a single site. After some early sites focused on business or dating, Myspace and Friendster helped popularize social media for personal use in the early 2000s. Today, Facebook is the most popular social network globally.