A trailer refers to a vehicle that is towed by a car and does not have a power drive itself. A combination of one car (truck or tractor, forklift) and one or more trailers. Trucks and tractors are the driving sections of the car train and are called main cars. The driven vehicle section pulled by the main vehicle is called a trailer. It is an important vehicle type for road transportation. The use of automobile train transportation is the most effective and simple important means to improve economic efficiency. It has the advantages of speed, maneuverability, flexibility and safety; it can easily realize section transportation.
