ABS stands for Antilock Braking System. When you press on the brake urgently, the ABS applies and releases the brakes hundreds of times a minute. That helps keep the brake from locking up the wheels and sending you into a skid. It helps you keep control and stop in the shortest distance under most conditions.
During normal braking, the ABS and non-ABS brake pedals feel the same. When you stomp on ABS brakes, though, you'll feel a pulsing in the brake pedal. The pedal may also fall and then rise, and there may be a clicking sound. Don't let any of that stop you from braking hard. Just keep your foot down and let the ABS do its thing.
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