AT&T is an American multinational corporation that provides telecommunications and digital entertainment services. It is the second largest provider of mobile telephone and the largest provider of fixed telephone in the United States. The company operates through three segments: Wireless, Wireline and International. Its provides wireless communications, data/broadband services, video services, telecommunications equipment, managed networking and much more. It currently has 128.6 million mobile customers and 243,620 employees. AT&T is headquartered in Dallas, Texas.