Chat Rooms
A place online where a group of people can get together and chat about a particular subject or just to chat. Usually you will need to sign in at least so you have a name in the room and then you can see who else is in the room. Some chat rooms allow you to talk to one individual without the others seeing your conversation.
Examples: Chat rooms can be found that focus on virtually any aspect of human endeavor or interest: there are current communities based on classic movies, Irish ancestry, baton twirling, and psychic readings, for example. Various sites, such as Yahoo, provide a directory of chat sites. Others, such as MSN Web Communities, guide users through the steps required to create their own chat room.

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Blogs
(n.) Short for Web log, a blog is a Web page that serves as a publicly accessible personal journal for an individual. Typically updated daily, blogs often reflect the personality of the author.

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Social Networking Sites
A web-based services that allow individuals to (1) construct a public or semi-public profile within a bounded system, (2) articulate a list of other users with whom they share a connection, and (3) view and traverse their list of connections and those made by others within the system. The nature and nomenclature of these connections may vary from site to site.
Examples: Facebook, Myspace, Twitter, Foursquare, and Tumbler.
[http://www.tweepi.com|http://www.tweepi.com]

online-social-networking.com
Virtual Worlds
A computer mediated reality which presents the user with an experience which can be reasoned about as if it was a world. Using an "avatar" people can interact and communicate with others in this extensive and absorbing 3D places.
Examples: Second Life, Active, Worlds.
Second Life

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