Long distance telephone call

In telecommunications, a long-distance call or trunk call is a telephone call made outside a defined local area, usually to another city. These calls are typically characterized by their higher per-minute cost ("national rate" or "overseas rate" instead of local rate), by terminating at a destination served by a different local telephone exchange or by being carried over intercity trunks or interexchange carriers instead of a direct line between two adjacent exchanges. A long-distance call is not necessarily synonymous with a call to another telephone area code.

Long-distance calls are classified into two categories: national calls when they connect two points within the same country and international calls when they connect two points from different countries.

Before direct distance dial (first introduced in a handful of markets in 1951), all long-distance calls were operator assisted by a special long-distance operator even in exchanges where calls within the local exchange were direct dial. Completion of intercity 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 some countries (such as Canada and the United States) long-distance rates were historically kept artificially high to subsidise unprofitable flat-rate local residential services. Intense competition between long-distance phone companies narrowed these gaps significantly in most developed nations in the late 20th century, although international calls to some countries continue to carry artificially high tolls as governments in those nations use them as a lucrative source of tax revenue.

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