Bogie A structure fitted beneath a carriage, wagon or locomotive, to which two or three pairs of wheels are attached. A bogie absorbs shocks and helps the train to turn corners. Also known as truck.

Diesel-electric locomotive A modern train in which the wheels are driven by electric motors, but the electricity is generated by a diesel engine. Because it provides its own power, a diesel-electric locomotive can run on any track.

Electric locomotive A modern train in which the wheels are moved by electric motors, usually one for each pair of wheels. Electricity is provided by overhead cables or an electrified third rail. The fastest trains, such as the Japanese Sinkansen, the Chinese CRH or the French TGV, are electrically powered. 

Freight train A line of goods wagons pulled by a locomotive on a railway line. Freight trains can carry large amounts of cargo long distances overland. This is cheaper than moving goods by road or air.

Funicular railway A railway that ascends a steep slope. Carriages are connected to a cable that runs up and down the slope. Ascending carriages are pulled up by the weight of the descending carriages, as the cable winds around a pulley at either end of the line.

High-speed rail (HSR) A system in which trains travel much faster than most other trains—usually more than 200 km/h (125 mph). HSR consists of specially engineered rolling stock running on purpose-built tracks that no other trains use. The first high-speed train, the Japanese Shinkansen (“bullet train”), started services in 1964. China currently has more than two-thirds of the world's total high speed rail, with more than 37,900 km (23,500 miles) of track.

Intercity-Express (ICE) The high-speed, electric-powered train service that runs through Germany and its neighbouring countries. Streamlined ICE trains travel at speeds of up to 300 km/h (188 mph), stopping only at major cities.

Locomotive A rail vehicle that provides the power for a train. There are two main types of modern locomotive: electric and diesel-electric.

Maglev train A type of train that moves by magnetic levitation. Powerful magnets fixed to the track push away from those fixed to the train in such a way that the train continually moves forwards while being suspended above the track. Because there is little friction, maglevs can reach very high speeds.

Monorail A kind of train that runs on a single rail, either above the track as in a normal train, or suspended beneath the rail, from a bridge or other structure. Almost all monorails are powered by an electric rail.

Pantograph A device on a locomotive that collects electricity from overhead cables in order to power its motor. Electronic circuits control the flow of electricity to the motors.

Passenger train A line of railway cars (also called carriages or coaches), designed to carry passengers. Passenger trains have seats, luggage storage areas, lavatories and cafés.

Power car A vehicle (usually the lead carriage) that propels, and often controls, a passenger train or tram. Unlike a locomotive (which can be detached), a power car is an integral part of the train. Nearly all high-speed trains have power cars, usually at both ends.

Railway track (also known as permanent way) is the structure on a railway consisting of steel rails, sleepers (or railroad ties) and ballast (or slab track), the bed of crushed stone on which the sleepers are laid.

Rapid transit A passenger train, also known as an underground, metro or subway, that links up areas of a city. Trains often travel beneath the streets in the city centre but above ground in the suburbs. All underground trains are powered by electricity.

Rolling stock Railway vehicles, either powered or unpowered. They include locomotives, freight cars and passenger cars (also called carriages or coaches). The rolling stock in a train is also known as a consist. 

Shinkansen A Japanese high-speed train, also known as the “bullet” train, that travels at speeds of up to 300 km/h (190 mph). Carriages are pressurized in such a way that passengers feel no difference when the train enters tunnels at high speed.

Shunter A small locomotive used to push other trains around, for example to move them from one track to another.

Train A connected series of railway vehicles, including a locomotive or power car and freight or passenger cars, that runs along a railway track. Some specialized trains, such as maglevs and monorails, have specially designed tracks.

Train à Grande Vitesse (TGV) France’s high-speed, electric-powered locomotive. It holds the record speed for the fastest wheeled train of 575 km/h (357 mph).

Tram An electric rail vehicle that runs on tracks on city streets.

Trans-Siberian Express The longest train service in the world, travelling 9297 kilometres (5775 miles) from Moscow to Vladivostok. The journey takes nearly eight days.

Consultant: Chris Oxlade