A slot is a narrow opening into which something else can be fitted, especially one used in a machine for receiving coins or tokens. It may also refer to a position in a series or sequence, such as a job, room, or time period. A slot is also a device for holding and positioning an aircraft wing or tail surface, as part of a high-lift or control system.

A casino game, also called a slot machine or fruit machine, is a gambling machine that uses reels to display combinations of symbols and requires a player to press a button to initiate spins. Each spin of the reels and landing of symbols on a payline results in a win or loss depending on the combination and amount wagered. The odds of hitting a particular combination are determined by the random number generator (RNG) running on the machine.

Many researchers have examined the enjoyment of playing slots, and their findings are consistent with the theory that people enjoy gambling as a form of escapism from painful emotional experiences. Their enjoyment is attributed to several factors, including the high-fidelity attention-capturing music and animations that accompany each spin, as well as the randomness of the wins and losses. This article expands on this research by investigating the role of reward reactivity in explaining why some players find the experience of slot play enjoyable, while others do not.