A slot car  is a powered miniature auto or other vehicle that is guided by a groove or slot in the track on which it runs.  A pin or blade extends from the bottom of the car into the slot. Though some slot cars are used to model highway traffic on scenic layouts, the great majority are used in the competitive hobby of slot car racing or slot racing.

Slot cars are usually models of actual automobiles, though some have bodies purpose-designed for miniature racing. Most enthusiasts use commercially-available slot cars (often modified for better performance), others motorize static models, and some “scratch-build,” creating their own mechanisms and bodies from basic parts and materials.

Drivers generally use a hand-held controller to regulate a low-voltage electric motor hidden within the car. Traditionally, each car runs on a separate lane with its own guide-slot (though recently-developed digital technology can allow cars to share a lane). The challenge in racing slot cars comes in taking curves and other obstacles at the highest speed that will not cause the car to lose its grip and spin sideways, or to ‘deslot’, leaving the track altogether.

Some enthusiasts, much as in model railroading, build elaborate tracks, sculpted to have the appearance of a real-life racecourse, including miniature buildings, trees and people. Hobbyists whose main goal is competition often prefer a track unobstructed by scenery.