A car's wing mirror, otherwise known as a side mirror, is a vital component of any vehicle that provides the driver with an expanded field of vision. Some other synonyms commonly used to refer to wing mirrors include side-view mirror, door mirror, outside mirror, and fender mirror. These terms all describe the same device that is attached to the exterior of a car, typically on the driver and passenger sides. While the main function of a wing mirror is to improve safety on the road, some drivers also use them to make parking easier or to check their appearance before exiting the vehicle.