AT&T is a data, voice, Internet service provider, and broadband/subscription television service provider. AT&T is the seventh largest company in the United States by total revenue. The current corporate structure of AT&T was formed in 2005 by a merger of SBC and AT&T. Based in Texas, SBC gained a presence in Illinois when it acquired Ameritech, a Chicago-based telecommunications provider. In 2005, SBC acquired AT&T, a diversified telecommunications company with long distance, cellular and cable interests.