Vacuum assisted brakes work by using a vacuum to help push the brake pads against the rotor. This helps to create a more friction and results in a quicker stop. The brake pedal still needs to be pressed down in order to activate the brakes, but the vacuum helps to create a stronger hold and results in less wear on the brakes. This type of brake is often used in performance cars and race cars, as it can provide a significant improvement in stopping power.