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In telecommunications, a long-distance call (U.S.) or trunk call (also known as a toll call in the U.K. ) is a telephone call made to a location outside a defined local calling area. Long-distance calls are typically charged a higher billing rate than local calls. The term is not necessarily synonymous with placing calls to another telephone area code. Long-distance calls are classified into two categories: national or domestic calls which connect two points within the same country, and international calls which connect two points in different countries. Within the United States there is a further division into long-distance calls within a single state (intrastate) and interstate calls, which are subject to different regulations (counter-intuitively, calls within states are usually more expensive than interstate calls). Not all interstate calls are long-distance calls. Since 1984 there has also been a distinction between intra-local access and transport area (LATA) calls and those between different LATAs, whose boundaries are not necessarily state boundaries. Before direct distance dialing (DDD), all long-distance calls were established by special switchboard operators (long-distance operators) even in exchanges where calls within the local exchange were dialed directly. Completion of long-distance calls was time-consuming and costly as each call was handled by multiple operators in multiple cities. Record keeping was also more complex, as the duration of every toll call had to be manually recorded for billing purposes. In many less-developed countries, such as Spain, Mexico, Brazil, and Egypt, calls were placed at a central office the caller went to, filled out a paper slip, sometimes paid in advance for the call, and then waited for it to be connected. In Spain these were known as locutorios, literally "a place to talk". In towns too small to support a phone office, placing long-distance calls was a sideline for some businesses with telephones, such as pharmacies.
Jean-Philippe Ansermet, Haiming Yu, Jilei Chen, Yao Zhang, Song Liu, Rundong Yuan, Cheng Song
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