A steam locomotive is a railway locomotive that produces its pulling power through a steam engine. These locomotives are fueled by burning combustible material, usually coal, wood or oil, to produce steam in a boiler. The steam moves reciprocating pistons which are mechanically connected the locomotive's main wheels. Both fuel and water supplies are carried with the locomotive, either on the locomotive itself or in wagons (tenders) pulled behind.
The US started developing steam locomotives in 1830 with the Baltimore and Ohio Railroad's Tom Thumb. This was the first US-built locomotive to run in America, Stourbridge Lion being the first, although it was intended as a demonstration of the potential of steam traction, rather than as a revenue-earning locomotive. Many of the earliest locomotives for American railroads were imported from Great Britain, including the Stourbridge Lion and the John Bull (still the oldest operable engine-powered vehicle in the United States of any kind, as of 1981) but a domestic locomotive manufacturing industry was quickly established, with locomotives like the DeWitt Clinton being built in the 1830s -wikipedia