A long-distance call is a "trunk call" in British English, but is a "toll call" in American English, though neither term is well known among younger Americans. The distinction is a result of historical differences in the way local service was billed; the Bell System traditionally flat-rated local calls in all but a few markets, subsidising local service by charging higher rates, or tolls, for intercity calls, allowing local calls to appear to be free. British Telecom (and the British Post Office before it) charged for all calls, local and long distance, so labelling one class of call as "toll" would have been meaningless.