As social networks proliferate, they are changing the way people think about the Internet, from a tool used in solitary anonymity to a medium that touches on questions about human nature and identity.
If Facebook were a country, it would be the fourth most populous in the world, just behind the U.S. Almost half of its users visit every day.
Nielsen Online reports that social networking (and associated blogging) is now the fourth most popular online activity. Time spent on social-networking sites is growing at three times the rate of overall Internet usage, accounting for almost 10 percent of total time spent online.
Social networks can lessen loneliness and boost self-esteem. But they can also have the opposite effect, depending on who you are and how you use these forums.