How does the air brake system primarily differ from hydraulic brake systems?

The air brake system primarily differs from hydraulic brake systems in that air brakes operate using compressed air, while hydraulic brakes rely on fluid pressure. In an air brake system, air is compressed in tanks and used to apply pressure to the brake shoes or pads, engaging the braking mechanism. This fundamentally alters how braking force is generated and applied.

In contrast, hydraulic brakes function by using a liquid (brake fluid) to transfer force from the brake pedal to the brake components. The mechanics behind the two systems are significantly distinct, which contributes to their unique characteristics and applications in various types of vehicles. For example, air brakes are commonly used in large commercial vehicles like trucks and buses due to their ability to provide greater braking force and accommodate the large volume needed for such vehicles, while hydraulic brakes are typically found in lighter vehicles like cars. The fundamental difference in their operating principles is what sets them apart and dictates their usage in the automotive industry.