A social network is an online community where a registered user can interact with other registered users. Typically, the user is encouraged to create a "profile" which contains basic information about the individual. Users interact with each other in a variety of ways: status updates, private messages, photo sharing & tagging, blogs, website links.

Some popular social networks in some ways mirror old-school business "intranets" in that the interaction and information contained within them is visible only within the "walled-garden" of the social network (a la Facebook.) Other social networks (MySpace among them,) have less concrete boundaries and the information can be seen by non-users or users who are not within an individual's "network."

Major Sites: Facebook, MySpace, Friendster, Orkut, Bebo