Control theory can be applied to various vehicle dynamics problems, such as enhancing stability, handling, and performance of vehicles. Some of the examples are: anti-lock braking system (ABS), traction control system (TCS), electronic stability control (ESC), active suspension system (ASS), and adaptive cruise control (ACC). ABS is a system that prevents the wheels from locking during braking, and improves the braking efficiency and steerability. TCS is a system that prevents the wheels from slipping during acceleration, and improves the traction and acceleration. ESC is a system that detects and corrects oversteer and understeer, and improves the stability and safety. ASS is a system that adjusts the stiffness and damping of the suspension, and improves the ride comfort and handling. ACC is a system that automatically adjusts the speed and distance of the vehicle to the preceding vehicle, and improves the fuel efficiency and traffic flow.