Door windows, encompassing both fixed and operable glass panels, are integrated into vehicle door assemblies to provide visibility, weather protection, and structural support. Operable windows utilize a regulator mechanism – typically cable, scissor, or rack-and-pinion – for vertical travel within the door frame. Glass composition commonly includes tempered or laminated safety glass for impact resistance and fragment retention. Window guides, consisting of channels and seals, ensure smooth operation and prevent water/wind ingress. Power window systems incorporate a motor, switch, and wiring harness to enable remote control of the window regulator.