Subsidiary of AT&T that provides voice, video, data, and Internet telecommunications
AT&T Corporation, originally the American Telephone and Telegraph Company, is the subsidiary of AT&T Inc. that provides voice, video, data, and Internet telecommunications and professional services to businesses, consumers, and government agencies.
During its long history, AT&T was at times the world's largest telephone company, the world's largest cable television operator, and a regulated monopoly. At its peak in the 1950s and 1960s, it employed one million people and its revenue ranged between $3 billion in 1950 ($34.7 billion in present-day terms) and $12 billion in 1966 ($97.9 billion in present-day terms).
In 2005, AT&T was purchased by Baby Bell and former subsidiary SBC Communications for more than $16 billion ($20.9 billion in present-day terms). SBC then changed its name to AT&T Inc.
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