Today’s motorcycles and cars are equipped with a very efficient braking system. They are so efficient that your vehicle stops safely, within a fraction of a second, in the case of an emergency. You pull the brake lever, the brake fluid, near to the lever travels all the way down through the brake pipes, and the brake pads are activated. This braking system that you just saw was developed over the last five decades of research and practical experiences. Let’s learn how engineers developed such an efficient braking system, or more specifically, let’s learn the interesting physics behind disc brakes.