AT&T is the dominant local phone company in 22 states, serving about 55 million local phone lines and 15 million high-speed Internet users. The firm also provides phone and data services, such as Web hosting and data transport, to businesses nationwide, notably large corporations. AT&T owns 100% of AT&T Mobility, the second-largest U.S. wireless carrier with 77 million customers. The firm also owns a directory publishing business and a handful of international investments.
