Steering wheels are the primary input device for vehicle directional control, mechanically linked—directly or via power-assist systems—to the steering gear. Typically constructed from metal, plastic, or composite materials, they transmit rotational force from the driver to the steering column. Modern steering wheels often integrate driver-facing controls for audio, telephony, and driver-assistance functions. Internal construction includes a central hub for mounting, spokes for structural support, and a rim providing the driver interface. Variations include diameter, grip texture, and material composition to optimize driver control and comfort.