The braking system in a modern car consists of the brake pedal, a power brake booster, brake master cylinder, brake lines, brake fluid, brake rotors (including calipers and pads), and, for some vehicles, brake drums (including wheel cylinders and brake shoes). In addition, all vehicles have a parking/emergency brake. Taken together, these components operate in sync to slow or stop your car. They operate like this: when you press on the brake pedal, the pressure you apply is multiplied by the brake booster. It is then distributed by the brake master cylinder and sent via the brake fluid through the brake lines to each individual wheel. When it arrives at a wheel, this pressure causes, for instance, the caliper (in a vehicle with disc brakes) to close, which then causes the pads to come in contact with the brake rotor. The resulting friction causes the car to slow down and eventually stop. Should this system fail, then the emergency brake may be used as a backup to stop your vehicle.