Most cars have at least one "dome light" (or "courtesy light") located in or near the ceiling of the passenger compartment, to provide illumination by which to fasten seatbelts and enter or exit the car. These often have an option to switch on when the front (or any) passenger doors are opened. Many vehicles have expanded this feature, causing the overhead interior light to remain on after all doors are closed, allowing passengers to fasten seat belts with added illumination. Another name for Dome is Festoon. These bulbs have dual ends, which usually are found in Dome-Housing.
