Twitter, Inc. was an American social media company based in San Francisco, California. The company operated the social networking service Twitter and previously the Vine short video app and Periscope livestreaming service. In April 2023, Twitter merged with X Holdings and ceased to be an independent company, becoming a part of X Corp.Twitter was created by Jack Dorsey, Noah Glass, Biz Stone, and Evan Williams in March 2006 and was launched that July. By 2012, more than 100 million users tweeted 340 million tweets a day, and the service handled an average of 1.6 billion search queries per day. The company went public in November 2013. By 2019, Twitter had more than 330 million monthly active users.On April 25, 2022, Twitter agreed to a $44 billion buyout by Elon Musk, CEO of SpaceX and Tesla, one of the biggest deals to turn a company private. On July 8, Musk terminated the deal. Twitter's shares fell, leading company officials to sue Musk in the Chancery Court of Delaware on July 12. On October 4, Musk announced his intention to purchase the company as he had agreed, for $44 billion, or $54.20 a share; the agreement closed on October 27.

Following Musk's takeover, Twitter was criticized for an increase in hate speech, as well as for perceived systemic prioritization of right-wing content. His acquisition of the company has been characterized by large-scale policy changes, mass layoffs and resignations, and a dramatic shift in the company's work culture.