A long time ago, automobiles were in their infancy and there was no way to stop a moving automobile. Then brakes came along. Brakes were devices that slowed or stopped a moving vehicle and prevented it from moving again.
Early braking devices consisted of curved wooden blocks designed to bear against the steel tires. This was manipulated using a single leverage system from the driver's seat. This "brake shoe" was the normal way of braking, either a horse-drawn vehicle or even a steam locomotive. Different designs, using levers, rods and pivots, were used to operate them.
By the end of the 20th century, the Michelin brothers began the movement, shifting away from the old way of braking. As automobiles shifted to pneumatic rubber wheels, new ideas of braking were needed, as "brake shoes" were no longer apt for the situation.
A new method (which has two kinds), in which attempted to apply the force of friction to the axle or to a drum on the axle or even to the transmission shaft, was used. This braking system was activated when the driver pushed a pedal down or operated a lever. Continuously applying pressure until it was heavy enough caused the bands to contract more slightly around the drum, giving it more greater retardation.
One instrument used a wooden block inside a flexible contracting metal band, which, when pressed together, would tighten around the drum. This causes friction between the drum, which is then connected to the wheel, then to the wooden blocks on one end, and eventually slowed down the vehicles' forward progress.
The other used an inner wheel or brake drum which had an added external contracting meant to wrap around the drum, slowing down or preventing the vehicle from moving forward. But this meant that the drum had to be constantly replaced, leading to poor friction quality.
Past forward to the 21st century. Newer braking systems, which used hydraulic fluids and the like to stop a vehicle became in vogue. One such system used a vacuum. The vacuum became a tool, in which it operated a brake booster. Modern cars, such as your Volkswagen, uses this method in its .
Another method to stop moving vehicles meant using disc brakes. Friction is applied on the discs, courtesy of brake pads mounted on brake calipers. Your VW brake parts are equipped with brake calipers that would apply the necessary amount of friction on the discs to slow or stop the car.
So start giving attention to the way your car behaves, especially when you step on the brakes. Any squealing noise, leaking or pulling coming from your can be a potential disaster waiting to happen. If these happen, take your Volkswagen to the nearest dealership and have the brakes inspected and even replaced. Your life and your loved ones depend on that little piece of machinery.