ABS mean

              In automotive speak ABS stands for antilock braking system, which is a safety feature that prevents wheel lockup and skidding during emergency braking. Antilock braking systems pump the brakes up to 20 times per second, allowing drivers to keep control of the vehicle during an emergency braking maneuver.

On older cars — or any car without antilock brakes — you should pump the brakes in a crude attempt to prevent skidding. Antilock brakes do a quicker and more precise job of pumping the brakes than a person ever could. If you’re driving a car with antilock brakes and have to make an emergency stop, it’s recommended to stomp on the brake pedal, hold firm pressure and steer out of the way if needed.

Antilock brakes have a unique feel when the system is activated; the pedal usually pulsates very quickly, so don’t be alarmed if this happens during emergency braking; just keep your foot planted.

Antilock brakes are available on just about every new car; if they’re not standard equipment, they’re generally not an expensive option. 

easy words:     

           ABS means anti/lock breaking system. In the older cars and in some newer cars they use disc breaks. When you slam the on the breaks with disc breaks they lock up and your rearend slides with a final meaning of losing control. The ABS breaks allow you to slam your breaks on without them locking up giving you better control of your vehicle. 

I always understood ABS to mean "Ability to Brake and Steer" as opposed to anti-lock braking system