Jack Dorsey is the founder of Twitter and co-founder of Square. He developed the idea for Twitter in 2000 while working at a dispatch company, creating a prototype with Biz Stone in 2006. Twitter launched in 2006 and grew rapidly after its use at SXSW in 2007. Dorsey served as Twitter's first CEO and currently serves as CEO of Square, which allows anyone to accept payments via mobile devices. Under Dorsey's leadership, Twitter has become a major platform for real-time news and communication, while Square processes over $11 million in transactions daily.