Twitter is an online social networking service and microblogging service that enables its users to send and read text-based posts of up to 140 characters, known as "tweets". It was created in March 2006 by Jack Dorsey and launched that July. The service rapidly gained worldwide popularity, with over 500 million active users as of 2012, generating over 340 million tweets daily and handling over 1.6 billion search queries per day.
Since its launch, the Twitter website has become one of the top 10 most visited on the Internet, and has been described as "the SMS of the Internet".
Twitter's ability to reach a broad audience for only the cost of the time required to write and publish tweets has made it a powerful marketing asset.