A disc brake is a type of braking system commonly used in vehicles, including cars and bicycles. It consists of a flat, circular metal disc that rotates with the wheel. When the driver presses the brake pedal, brake pads clamp down on the disc, creating friction that slows down or stops the vehicle. Disc brakes are known for their effective heat dissipation, which helps prevent brake fade during prolonged use. They are often preferred over drum brakes for their superior performance in wet conditions and their ability to provide consistent stopping power. Components like the brake caliper and brake pads are essential for their operation.