An automobile

Automobile

An automobile, autocar, motor car or car is a wheeled motor vehicle used for transporting passengers, which also carries its own engine or motor...

 may have two to four foot pedals. The arrangement is the same for both right- and left-hand traffic. From left to right:

• normally operated by the left foot:
  • clutch
    Clutch
    A clutch is a mechanical device which provides for the transmission of power from one component to another...
    
     pedal, not in the case of automatic transmission
    Automatic transmission
    An automatic transmission is one type of motor vehicle transmission that can automatically change gear ratios as the vehicle moves, freeing the driver from having to shift gears manually...
    
    
• normally operated by the right foot:
  • brake
    Brake
    A brake is a mechanical device which inhibits motion. Its opposite component is a clutch. The rest of this article is dedicated to various types of vehicular brakes....
    
     pedal, which is sometimes wide and elevated above the car floor
  • throttle
    Throttle
    A throttle is the mechanism by which the flow of a fluid is managed by constriction or obstruction. An engine's power can be increased or decreased by the restriction of inlet gases , but usually decreased. The term throttle has come to refer, informally and incorrectly, to any mechanism by which...
    
     (known as the 'accelerator' or 'gas pedal'), controls fuel and air supply to the automobile's engine
    Engine
    An engine or motor is a machine designed to convert energy into useful mechanical motion. Heat engines, including internal combustion engines and external combustion engines burn a fuel to create heat which is then used to create motion...
    
    . It is usually narrow and close to the car floor allowing the driver's heel to rest on the car floor. It has a fail-safe
    Fail-safe
    A fail-safe or fail-secure device is one that, in the event of failure, responds in a way that will cause no harm, or at least a minimum of harm, to other devices or danger to personnel....
    
     design in that it automatically returns to the idle
    Idle (engine)
    When an engine running on idle or idles, the engine runs without any loads but the engine accessories.Effort has been made to reduce the amount of time engines spend idling, chiefly due to fuel economy and emissions concerns, although some engines can also be damaged if kept idling for extended...
    
     position when not depressed by the driver.

Some vehicles have a parking brake pedal instead of a hand brake

Hand brake

In cars, the hand brake is a latching brake usually used to keep the car stationary, and in manual transmission vehicles, as an aid to starting the vehicle from stopped when going up an incline - with one foot on the clutch , the other on the accelerator In cars, the hand brake (emergency brake,...

 lever. Pedals can be either 'hanging' from the firewall (bulkhead

Bulkhead (partition)

A bulkhead is an upright wall within the hull of a ship or within the fuselage of an airplane. Other kinds of partition elements within a ship are decks and deckheads.-Etymology:...

) or 'standing' on the floor.

Since the right foot is normally used (for the accelerator or brake) there is no foot rest on the right, not even in cars with cruise control

Cruise control

Cruise control is a system that automatically controls the speed of a motor vehicle. The system takes over the throttle of the car to maintain a steady speed as set by the driver.-History:...

. The left foot only has to operate the clutch intermittently (or has no function in an automatic vehicle) so sometimes a foot rest is provided to the left of the pedals. Some drivers practice left-foot braking

Left-foot braking

Left-foot braking is the technique of using the left foot to operate the brake pedal in an automobile, leaving the right foot dedicated to the throttle pedal...

, however.

Many cars now include pedals with electric adjustment, a modern iteration of a manual adjustment system available sporadically since the 1950s.

Other vehicles

Heavy vehicles on caterpillar tracks such as bulldozer

Bulldozer

A bulldozer is a crawler equipped with a substantial metal plate used to push large quantities of soil, sand, rubble, etc., during construction work and typically equipped at the rear with a claw-like device to loosen densely-compacted materials.Bulldozers can be found on a wide range of sites,...

s or tanks may have two brake pedals; for the left and right side tracks respectively. These vehicles do not have a clutch pedal but two manually operated levers - the clutches and brakes are used for differential steering

Steering

Steering is the term applied to the collection of components, linkages, etc. which will allow a vessel or vehicle to follow the desired course...

.

In a bulldozer the gas pedal operates in an opposite way to an automobile; depressed pedal = idle, released pedal = full open throttle.

A twin engined wheel tractor-scraper

Wheel tractor-scraper

In civil engineering, a wheel tractor-scraper is a piece of heavy equipment used for earthmoving.The rear part has a vertically moveable hopper with a sharp horizontal front edge. The hopper can be hydraulically lowered and raised. When the hopper is lowered, the front edge cuts into the soil or...

has two gas pedals next to each other; one for the front engine and one for the rear engine.