Tractor is a self-propelled power machine used to pull and drive working machinery to complete various mobile operations. It can also be used for fixed operation. It is composed of engine, transmission, walking, steering, hydraulic suspension, power output, electrical instrument, driving control and traction system or device.
The engine power of the tractor is transmitted from the transmission system to the driving wheel to make the tractor run. In real life, rubber belt is commonly used as the medium of power transmission. According to the function and use, it can be divided into agricultural, industrial and special purpose tractors; according to the structure type, it can be divided into wheeled, crawler, boat tractor and self-propelled chassis.