Trains are powered by fuel. The diesel locomotive and electrified locomotive are mainly used. At present, trains in China have three kinds of power.
1. Steam locomotive: coal is burned in a boiler to boil water into steam, which drives pistons and wheels.
2. Diesel locomotive: first use the diesel engine to drive the generator to generate electricity, and then use the motor to drive the wheels.
3. Electric locomotive: directly use the motor to drive the wheels to rotate, and the locomotive moves to drive the train.
The most important machine in human history, called steam locomotive in the early days, has its own track. According to the load, railway trains can be divided into freight cars and passenger cars, and there are also passenger and freight mixed vehicles of both. During this period, trains used coal as fuel.
Train is a typical example of human transportation using fossil energy. In 1804, Derevsk, a British mining technician, used Watt's steam engine to build the world's first steam locomotive, with a speed of 5 to 6 kilometers per hour. Because coal or firewood was used as fuel at that time, people called it "train", which has been used until now. On February 22nd, 1840, Charles Livisik, an engineer from Cornwall, designed the world's first real train running on the track.