What type of brake uses a rotor and caliper on bicycles?

The type of bicycle brake that uses a rotor and caliper is a disc brake.

A disc brake has a metal rotor attached to the wheel hub. When the rider squeezes the brake lever, pads inside the caliper clamp the spinning rotor and convert the bicycle’s motion into heat. The system may be mechanical, using a cable, or hydraulic, using fluid to move pistons in the caliper.

Unlike a rim brake, which presses pads against the wheel’s rim, a disc brake places its braking surface near the hub. That design helps maintain braking performance in wet or muddy conditions and allows bicycles to use wider tyres, suspension and different wheel sizes without changing the brake’s position. Disc brakes are especially common on mountain bikes and downhill bicycles.

Drum and coaster brakes work through different mechanisms. A drum brake encloses its braking parts inside a hub, while a coaster brake engages when the rider pedals backward. Disc brakes can offer strong, predictable control, but their rotors may become hot, bent or contaminated, and worn pads require replacement.