AT&T refers to several related companies providing telecommunications services:

• History of AT&T, a history of the various companies using this name, including:
  • AT&T Corporation, the original AT&T founded 1885 (formerly American Telephone & Telegraph), now a subsidiary of AT&T, Inc.
    • AT&T Communications Inc., provided long-distance services for AT&T Corporation (defunct)
  • AT&T, Inc., the current company providing a wide range of telecommunications service, originally one of the Baby Bells which acquired other systems, and formerly known as Southwestern Bell Corporation (SBC)
    • AT&T Communications, houses most of AT&T Inc.'s Telecommunications and Technology Businesses
  • Bell System, known as Ma Bell, AT&T Corporation's system of companies that held a monopoly on phone service in the US for most of the 20th century
  • Regional Bell Operating Company, known as Baby Bells, the companies formed from AT&T Corporations's 1984 split

AT&T may also refer to:

Telecommunications

• AT&T Bell Laboratories, a former research & development subsidiary of AT&T
• AT&T Corporation, the original AT&T founded 1885 (formerly American Telephone & Telegraph), purchased by SBC in 2005
  • AT&T Information Systems, founded 1982 (formerly American Bell), an unregulated business subsidiary of AT&T Corp.
  • Alascom dba AT&T Alascom, founded 1900 (formerly Washington-Alaska Military Cable and Telegraph System), a long-distance company
• AT&T Labs, founded 1988 (formerly Southwestern Bell Technology Resources), the R&D division of AT&T Inc.
  • AT&T Laboratories, founded 1925 as part of Bell Labs and AT&T Corp., later spun off and now absorbed into AT&T Labs
• AT&T Communications (formerly AT&T Long Lines), an operating company serving the regions of the Bell Operating Companies
  • AT&T CallVantage, a voice-over-internet-protocol service formerly offered by AT&T Corp. and then AT&T Inc.
• AT&T Mobility, the wireless provider subsidiary of AT&T Inc. (formerly Cingular Wireless)
  • AT&T Wireless Services, the former wireless provider subsidiary that became part of Cingular Wireless
• AT&T Technologies, founded 1983, a telephone producer, the postdivestiture successor to Western Electric
• AT&T Broadband, founded 1999 (now part of Comcast), once the largest U.S. provider of cable television services
• Advanced American Telephones, founded 1983, a manufacturer of AT&T branded phones (formerly AT&T Consumer Products)
• Bell Labs, founded 1925 (formerly also called Bell Telephone Laboratories, Inc., and later AT&T Bell Laboratories), a Nobel Prize–winning research and development organization
• Lucent, founded 1983 (now part of Alcatel-Lucent), the primary successor to Bell Labs and AT&T Technologies

Locations

• One AT&T Plaza (Whitacre Tower), headquarters of AT&T Inc.
• AT&T Building (disambiguation), the name of several buildings
• AT&T (SEPTA station), a station on SEPTA's Broad Street Line in Philadelphia
• AT&T Stadium, home stadium of the Dallas Cowboys of the National Football League (NFL)
• Jones AT&T Stadium, home stadium of the Texas Tech Red Raiders of the National Collegiate Athletic Association (NCAA)
• AT&T Park, home park of the San Francisco Giants of Major League Baseball (MLB)

Other

• AT&T, assembly language syntax
• Aircraft Transport and Travel, a 1910s British airline

See also

• AT&T breakup