A brake booster improves brake safety and the performance of a braking system. This type of system works by increasing the force applied to the brake pedal by creating a vacuum.
The brake booster contains a mechanism that separates its internal pieces into two parts, and both of these parts create a partial vacuum. When the driver presses on the brake pedal, a valve inside the brake booster opens, allowing air into one side of the booster. This uneven pressure pushes one side of the piston in the master cylinder forward and slows and stops the vehicle more efficiently than a master cylinder alone, notes CarsDirect.com.
Brake boosters are more common in contemporary times because of the use of disc brakes in vehicles. In older cars, drum brakes provided more power assistance than modern disc brakes, so a brake booster usually was not needed. Most disc brake systems may benefit from the use of a brake booster to prevent the driver from having to push the brake pedal too hard to safely slow or stop a vehicle.
Without a brake booster, drivers have to exert more effort and subsequently suffer more fatigue while stopping a vehicle. Brake boosters help drivers slow their vehicles and help prevent wear and tear on a car's brakes.