A train 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 or railcars, though some are self-propelled, such as multiple units. Passengers and cargo are carried in railroad cars, also known as wagons. 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.
An electric locomotive pulling a passenger train in Russia
A rack railway in Switzerland
Diesel locomotives pulling a freight train in New Zealand
A suspended monorail in Germany
A vehicle is a machine designed for self-propulsion, usually to transport people, cargo, or both. Vehicles include wagons, bicycles, motor vehicles, railed vehicles, watercraft, amphibious vehicles, aircraft, and spacecraft.
A bus, a common form of vehicle used for public transport
Motorcycles are used to transport light cargo quickly, in crowded cities, and on unpaved roads.
A Slavic dugout boat from the 10th century
Automobiles are among the most commonly used engine-powered vehicles.