ABS is the abbreviation of Anti-LockBrakeSystem, which means "anti-lock brake system". In the absence of ABS, emergency braking will generally cause the tires to lock up, and since the tires are sliding friction with the ground after locking up, the braking distance will become longer. If the front wheels lock up, the car will lose lateral steering force and easily run off; if the rear wheels lock up, the rear wheels will lose lateral grip and easily drift off. ABS is used to control wheel locking by controlling the brake pressure. The process of ABS is to quickly complete the cycle of "release and collection", so that the vehicle is always in the critical locking gap rolling state.