Public transport comprises all transport systems in which the passengers do not travel in their own vehicles. It is also called public transit or mass transit. While it is generally taken to mean rail and bus services, wider definitions would include scheduled airline services, ferries, taxicab services etc. — any system that transports members of the general public.

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Note added at 24 mins (2006-08-23 08:58:41 GMT)
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The term public transport is preferred in the British Isles and most Commonwealth countries, whereas public transportation, public transit or mass transit are usually used in North America.