Multiple unit in the context of "ICE 3"

Commuter rail or suburban rail is a passenger rail service that primarily operates within a metropolitan area, connecting commuters to a central city from adjacent suburbs or commuter towns. Commuter rail systems can use locomotive-hauled trains or multiple units, using electric or diesel propulsion. Distance charges or zone pricing may be used.

The term can refer to systems with a wide variety of different features and service frequencies, but typically refers to mainline rail services connecting suburban communities with city centres over medium distances; it is distinguished from rapid transit systems which operate inside the urban core.

The term rolling stock in the rail transport industry refers to railway vehicles, including both powered and unpowered vehicles: for example, locomotives, freight and passenger cars (or coaches), and non-revenue cars. Passenger vehicles can be un-powered, or self-propelled, single or multiple units.

In North America, Australia and other countries, the term consist (/ˈkɒnsɪst/ KON-sist) is used to refer to the rolling stock comprising a train, a list containing specific information for each car of a train, or a group of locomotives.

A train (from Old French trahiner, from Latin trahere, "to pull, to draw") is a series of connected vehicles that run along a railway track and transport people or freight. Trains are typically pulled or pushed by locomotives (often known simply as "engines"), though some are self-propelled, such as multiple units or railcars. Passengers and cargo are carried in railroad cars, also known as wagons or carriages. Trains are designed to a certain gauge, or distance between rails. Most trains operate on steel tracks with steel wheels, the low friction of which makes them more efficient than other forms of transport. Many countries use rail transport.

Trains have their roots in wagonways, which used railway tracks and were powered by horses or pulled by cables. Following the invention of the steam locomotive in the United Kingdom in 1802, trains rapidly spread around the world, allowing freight and passengers to move over land faster and cheaper than ever possible before. Rapid transit and trams were first built in the late 1800s to transport large numbers of people in and around cities. Beginning in the 1920s, and accelerating following World War II, diesel and electric locomotives replaced steam as the means of motive power. Following the development of cars, trucks, and extensive networks of highways which offered greater mobility, as well as faster airplanes, trains declined in importance and market share, and many rail lines were abandoned. The spread of buses led to the closure of many rapid transit and tram systems during this time as well.

A passenger train is a train used to transport people along a railroad line, as opposed to a freight train that carries goods. These trains may consist of unpowered passenger railroad cars (also known as coaches or carriages) hauled by one or more locomotives, or may be self-propelled; self propelled passenger trains are known as multiple units or railcars. Passenger trains stop at stations or depots, where passengers may board and disembark. In most cases, passenger trains operate on a fixed schedule and have priority over freight trains.

Car design and the general safety of passenger trains have dramatically evolved over time, making travel by rail remarkably safe. Some passenger trains, both long-distance and short-distance, use bi-level (double-decker) cars to carry more passengers per train. Sleeper trains include sleeping cars with beds. Passenger trains hauled by locomotives are more expensive to operate than multiple units, but have a higher passenger capacity.

Light rail (or light rail transit, abbreviated to LRT) is a form of passenger urban rail transit that uses rolling stock derived from tram technology while also having some features from heavy rapid transit.

The term was coined in 1972 in the United States as an English equivalent for the German word Stadtbahn, meaning "city railroad". Different definitions exist in some countries, but in the United States, light rail operates primarily along exclusive rights-of-way and uses either individual tramcars or multiple units coupled together, with a lower capacity and speed than a long heavy rail passenger train or rapid transit system.

A railroad car, railcar (American and Canadian English), railway wagon, railway carriage, railway truck, railwagon, railcarriage or railtruck (British English and UIC), also called a train car, train wagon, train carriage or train truck, is a vehicle used for the carrying of cargo or passengers on a rail transport network (a railroad/railway). Such cars, when coupled together and hauled by one or more locomotives, form a train. Alternatively, some passenger cars are self-propelled in which case they may be either single railcars or make up multiple units.

The term "car" is commonly used by itself in American English when a rail context is implicit. Indian English sometimes uses "bogie" in the same manner, though the term has other meanings in other variants of English. In American English, "railcar" is a generic term for a railway vehicle; in other countries "railcar" refers specifically to a self-propelled, powered, railway vehicle.

In rail transport, the expression power car may refer to either of two distinct types of rail vehicle:

• a vehicle that propels, and commonly also controls, a passenger train, potentially a multiple unit train, often as the lead vehicle;
• a vehicle equipped with machinery for supplying heat or electrical power to other parts of a train.

The first of these types of vehicle is closely related to the locomotive. What differentiates the locomotive and the first type of power car is their construction or use. A locomotive can be physically separated from its train and does nothing but provide propulsion and control (and heat or electricity for passenger trains). On the other hand, a power car of the first type is frequently an integral part of its train, and if the train uses distributed traction, some of the car's interior space may be used for carrying passengers or cargo.

A motor coach (international usage) or motorcar (US usage) is a self-propelled passenger rail vehicle also capable of hauling a train. With multiple unit train control, one operator can control several "motor coaches", possibly even combined with locomotives, efficiently in the same train, making longer trains possible.

Motor coaches can replace locomotives at the head of local passenger or freight trains. Especially electrified narrow gauge lines on the European continent often saw this form of operation. Many of these railways closed down, and many others changed to electric multiple units. However, a few lines in Switzerland, Italy and Austria still work with train consists hauled by motor coaches. It can be expected that the Bernina line of Rhaetian Railway will continue for a long time to be operated with motor coaches pulling passenger and freight trains.