Passive suspension systems are a type of vehicle suspension that uses mechanical components, such as springs and shock absorbers, to absorb road shocks and maintain vehicle stability. These systems do not require any external power or control systems, relying instead on the natural properties of the materials used. They are designed to provide a comfortable ride by minimizing the impact of bumps and uneven surfaces. The main components of passive suspension systems include coil springs, leaf springs, and hydraulic dampers. While they are generally simpler and more cost-effective than active systems, passive suspensions may not adapt as quickly to changing road conditions, which can affect handling and comfort in certain situations.