Are anti-lock brakes always activated when you depress the brakes?

Antilock brakes (ABS) are not always activated when you depress the brakes. ABS only activates when the sensors in the wheels detect a loss of traction, which can happen when braking hard on slippery roads or when making a panic stop. When ABS is activated, the brake pads intermittently release and reapply pressure to the rotors, which helps prevent the wheels from locking up and skidding.