A railcar is a self-propelled rail vehicle designed to transport passengers. Railcars usually consist of either one coach, with a drivers cab at each end, or sometimes two coaches fitted together with a permanent coupling, which operate as a single unit.
Railcars are usually propelled by a diesel engine mounted underneath the floor of the coach.
Sometimes when there are enough passengers to justify it, railcars can be joined together to form multiple units.
Railcars are economic to run because of their small size, and in many countries are often used to run passenger services on minor railway lines, such as rural railway lines where passenger traffic is sparse, and where the use of a longer train would not be cost effective.
A variation of railcar is a railbus, a very lightweight type of railcar designed for use specifically on little-used railway lines, and as the name suggests share many aspects of their construction with a bus, usually having a bus, or modified bus body, and having four wheels on a fixed base, instead of on bogies.