telecommunication Telecommunication is the transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems. It has its origin in the desire of humans for communication over a distance greater than that fe ...

, a long line is a transmission line in a long-distance

communications network A telecommunications network is a group of nodes interconnected by telecommunications links that are used to exchange messages between the nodes. The links may use a variety of technologies based on the methodologies of circuit switching, message ...

such as

carrier system A carrier system is a telecommunications system that transmits information, such as the voice signals of a telephone call and the video signals of television, by modulation of one or multiple carrier signals above the principal voice frequency or ...

microwave radio relay Microwave transmission is the transmission of information by electromagnetic waves with wavelengths in the microwave frequency range of 300MHz to 300GHz(1 m - 1 mm wavelength) of the electromagnetic spectrum. Microwave signals are normally lim ...

links, geosynchronous

satellite A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioisotope ...

links, underground cables,

aerial cable An aerial cable or air cable is an insulated cable usually containing all conductors required for an electrical distribution system (typically using aerial bundled cables) or a telecommunication line, which is suspended between utility poles o ...

s and

open wire Open wire was an early transmission technology in telecommunication, first used in telegraphy. It consisted of pairs of electric wire strung on a pole line between communities, towns, and cities. The wire of the transmission line was attached to ...

, and

Submarine communications cable A submarine communications cable is a cable laid on the sea bed between land-based stations to carry telecommunication signals across stretches of ocean and sea. The first submarine communications cables laid beginning in the 1850s carried tel ...

s. In the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

, some of this technology was spun off into the corporate entity known as ''AT&T Long Distance'' with the

breakup of AT&T The breakup of the Bell System was mandated on January 8, 1982, by an agreed consent decree providing that AT&T Corporation would, as had been initially proposed by AT&T, relinquish control of the Bell Operating Companies, which had provided loc ...

in 1984. Previously, the

AT&T Long Lines AT&T Communications, Inc., was a division of the AT&T Corporation that, through 23 subsidiaries, provided interexchange carrier and long-distance calling, long-distance telephone services. History AT&T Long Lines The American Telephone & ...

division of the

Bell System The Bell System was a system of telecommunication companies, led by the Bell Telephone Company and later by the American Telephone and Telegraph Company (AT&T), that dominated the telephone services industry in North America for over one hundr ...

provided maintenance and installation of long line facilities for the Bell System's long-distance service.

See also