While there are a variety of brake systems, all serve the same function: to slow down or stop your car when you apply the brake pedal. With disc brakes, the brake pad squeezes the rotor and the friction created slows the disc down. Over time, brake pads wear out and need to be replaced. Waiting too long to replace brake pads damages the rotors and makes the tires wear unevenly, which is why it’s important to have your brakes checked regularly.