A train is either the combination of locomotives and attached railroad cars (or 'carriages'), or a multiple unit (or occasionally a single powered coach, called arailcar), that runs on a railway. Special kinds of trains running on corresponding special 'railways' are monorail, high speed rail, rubber-tired underground,funicular and cog railway. Trains are for public transport or for freight. Multi-purpose trains, hauling both passengers and freight, have become rare in many countries.A passenger train[?] may consist of one or several locomotives, and one or more cars or carriages. Alternatively, a train may consist entirely of passenger carrying coaches, some or all of which are powered (multiple unit). Freight trains comprise wagons or trucks rather than carriages.For more than a century almost all trains were powered by steam engines, but most countries had phased steam trains out by the 1970s. A few countries, most notably China and India still use steam trains, but this is being gradually phased out.
