Twitter (/ twɪtər /) is a US online news and social networking service where users post and interact with messages known as “tweets”. The tweets were originally restricted to 140 characters, but on November 7, 2017, this limit doubled for all languages, except Chinese, Japanese, and Korean. Registered users can post, like and retweet tweets, but unregistered users can only read them. Users access Twitter through the interface of their website, through the Short Message Service (SMS) or their application software for mobile devices (“application”).  Twitter, Inc. is headquartered in San Francisco, California, and has more than 25 offices around the world.
Twitter was created in March 2006 by Jack Dorsey, Noah Glass, Biz Stone and Evan Williams and was launched in July of that year. The service quickly gained worldwide popularity. In 2012, more than 100 million users published 340 million tweets per day,  and the service served an average of 1.6 billion search queries per day. In 2013, it was one of the ten most visited websites and has been described as “Internet SMS”. As of 2016, Twitter had more than 319 million monthly active users. Since 2015, and continuing in 2016 and in future years, Twitter has also been the home of debates and news covering the United States Policy, especially during the 2016 presidential elections in the US. UU Twitter proved to be the largest source of breaking news on election day in 2016, with 40 million tweets related to the elections sent at 10:00 pm (Eastern Time) that day.
The turning point for the popularity of Twitter was the conference 2007 South by Southwest Interactive (SXSWi). During the event, the use of Twitter increased from 20,000 tweets per day to 60,000. “The people on Twitter intelligently placed two 60-inch plasma screens in the halls of the conference, exclusively broadcasting Twitter messages,” said Steven Levy of Newsweek. “Hundreds of conference attendees monitored each other through constant twitters, the panelists and speakers mentioned the service, and the bloggers present promoted it.” The reaction at the conference was very positive. Blogger Scott Beale said Twitter was “absolutely ruling” SXSWi. Social software researcher Danah Boyd said Twitter was “being the owner” of the conference. The Twitter staff received the Web Award of the festival with the comment “we would like to thank you in 140 characters or less and we did!”
The first unattended Twitter message outside of Earth was posted from the International Space Station by NASA astronaut TJ Creamer on January 22, 2010.  At the end of November 2010, an average of a dozen were published of updates per day in the community account of astronauts, @NASA_Astronauts. NASA has also organized more than 25 “tweetups”, events that provide guests with VIP access to NASA facilities and speakers with the goal of leveraging participants’ social networks to promote NASA’s outreach objectives. In August 2010, the company named Adam Bain of the News Corp. Fox Audience Network as president of revenue.