An automotive technology that automatically controls the speed of a vehicle. The driver sets a speed and the system takes over the throttle of the car to maintain a steady pace until the system is turned off manually or by tapping the brake pedal. It can help to conserve gas by avoiding surges. A newer adaptation is called adaptive cruise control, or ACC, which allows drivers to maintain a set speed while it monitors traffic and adjusts the “closing” distance to the vehicle ahead. ACC reads traffic conditions via radar, a light-based system or cameras, and adjusts the throttle and brakes to keep a safe distance.