•Your foot pushes on the brake pedal.•The break pedal pushes a piston (blue) into a master cylinder filled with hydraulic brakefluid (red).•The brake fluid squirts down a long, thin pipe until it reaches the slave cylinder at thewheel.•When the fluid enters the cylinder, it pushes the piston in the wider cylinder (blue) withan increased force.•The piston pushes the brakepad (green) toward the brakedisc (grey).•When the brake pad touchesthe brake disc, frictionbetween the two generatesheat. friction slows down the•Theouter wheel and tyre,stopping the car.
•Air brake systems are bulky, and •Hydraulic systems are smaller and lessrequire air compressors and reservoir tanks. expensive.•Air brakes, where a valve is opened and air •Hydraulic systems rely on a single stroke of aflows into the lines and brake chambers until piston to force fluid through the system.the pressure rises sufficiently. •With innovations like anti-lock brake•Compression problems with air brakes can systems, traction control, and electroniccause delays in braking performance. stability control, hydraulic brakes have become safe.•Air Brakes have a longer stoppingdistance. •Vehicles with hydraulic brakes have shorter stopping which arguably makes them a safer product.