The document discusses the evolution and current state of social media. It outlines some of the first social networking sites like USENET in 1979 and SixDegrees in 1999. Currently, over 300 social media sites exist with Facebook having over 200 million users and LinkedIn over 35 million professionals. Popular sites also include Twitter, Flickr, YouTube, and blogs. The document discusses advantages and disadvantages of these sites and how social media provides low-cost marketing and networking opportunities but can be difficult to control.