Twitter

  http://twitter.com/

Twitter is an online social networking service and microblogging service that enables users to send and read text-based posts of up to 140 characters, known as "tweets". It was created in March 2006 by Jack Dorseyand launched that July. The service rapidly gained worldwide popularity, with over 300 million users as of 2011,generating over 300 million tweets and handling over 1.6 billion search queries per day. It has been described as "the SMS of the Internet. Joining it, is free. You can join there by going to the