a type of steering setup. As the name implies, rack and pinion steering consists of two major components, a rack and a pinion. The rack, also known as a steering rack, is a long piece of metal that is flat on at least one side. The flat side contains teeth running the length of the rack. The teeth are cut perpendicular to the edges of the rack, meaning they run side by side from one end of the rack to the other, like teeth in a smile. The pinion, or more correctly, the pinion shaft, is a round rod that also has teeth on it, although these teeth run parallel to the length of the shaft, not lengthwise as on the rack. The pinion shaft comes into the rack at a ninety-degree angle, held in place by a collar, and the teeth on the pinion mesh with the teeth on the rack. The pinion is connected directly to the steering column, so when the steering wheel is turned to the left, for instance, the pinion rotates counter-clockwise (from the driver's perspective). The rotary motion of the pinion is changed to transverse motion by the rack. The rack moves to the right, making the wheels go left.