(for the panels around the wheels of a car see Fender (vehicle)
Fender is the US English term for the part of an automobile, motorcycle or other vehicle body that frames a wheel well . Its primary purpose is to prevent sand, mud, rocks, liquids, and other road spray from being thrown into the air by the rotating tire. Fenders are typically rigid and can be...
A wing in this context is an aerodynamic device
Automotive aerodynamics is the study of the aerodynamics of road vehicles. The main concerns of automotive aerodynamics are reducing drag , reducing wind noise, minimizing noise emission, and preventing undesired lift forces and other causes of aerodynamic instability at high speeds...
intended to generate downforce on an automobile. The first production car to feature a rear wing was the 1969 mercury cyclone spoiler, soon followed by the drastically larger Superbird and Daytona wings. The angle of attack
Angle of attack
Angle of attack is a term used in fluid dynamics to describe the angle between a reference line on a lifting body and the vector representing the relative motion between the lifting body and the fluid through which it is moving...
of the wing on some cars can be adjusted to increase downward force over the rear wheels, but drag is also increased. The simulation and testing of wings can be very expensive.
A spoiler is an automotive aerodynamic device whose intended design function is to 'spoil' unfavorable air movement across a body of a vehicle in motion. Spoilers on the front of a vehicle are often called air dams, because in addition to directing air flow they also reduce the amount of air...
are often confused with wings, and the terms are frequently (yet incorrectly) used interchangeably. Spoilers increase grip by reducing the lift created by a car's shape, and also reduce drag by eliminating the induced drag associated with that lift. Wings increase grip by producing downforce, at the expense of additional induced drag. Although identical in form to the wing of an aircraft
A wing is an appendage with a surface that produces lift for flight or propulsion through the atmosphere, or through another gaseous or liquid fluid...
, wings used in automotive applications are usually inverted (oriented upside-down) and sometimes reversed (oriented backwards) by comparison.