Are all car brakes hydraulic?

No, the foot brakes of cars are not all hydraulic brakes. Hydraulic brakes are often used in small vehicles, and are used in vehicles with less braking force.

There are many kinds of foot brakes, including hydraulic brakes, pneumatic brakes and mechanical brakes.

Hydraulic braking is used for minivans, cars and some motorcycles.

Pneumatic braking is mainly used for heavy trucks, trucks and large buses, which is characterized by strong braking force and low requirements for system sealing. But the sensitivity is worse than that of hydraulic braking.

Vacuum assist is only a part of the braking system, and it is often used in hydraulic system, because the vacuum assist method can greatly reduce the driver's stepping on the brake pedal and reduce the driver's load.

Nowadays, small vehicles are basically equipped with vacuum booster devices.

The above answers may not be comprehensive enough, so it is recommended to read relevant professional books.