AT&T

AT&T Inc. is an American multinational telecommunications holding company located at the Whitacre Tower in Downtown Dallas, Texas. It is the world's largest telecommunications company, the secon largest provider of mobile telephone services, and the largest provider of fixed telephone services in the United States throught AT&T Communications. Since June 15, 2018, it is also the parent company of mass media conglomerate WarnerMedia, making it the world's largest media and entertainment company in terms of revenue.