A slot is a place, time, or position in which something may be placed or inserted. In linguistics, a slot (plural slots) is an elongated depression, hole, groove, notch, slit, or aperture, especially one narrow enough for receiving or admitting something, such as a coin or letter.

A slot machine is a type of gambling machine that takes input from a player and pays out prizes depending on the combinations of symbols on the reels. Depending on the game, different types of slots exist, from classic fruit symbols to movie-inspired icons and themes. In addition, some slots are interactive and allow the player to select their own paylines.

The paytable area lists information on jackpot amounts for specific reel combinations and can also display some or all game theme rules. This area can be permanently displayed on the slot machine or, more commonly with touchscreen displays, a series of images can be switched between to view every possible win combination. The list of potential wins may be highly abbreviated or, mainly with touchscreen displays, may allow the user to select each reel to view its payouts individually.

Dixon et al. (2019) have shown that participants with mindfulness problems tend to endorse dark flow experiences during slot play more strongly than non-problem players. They suggest that this is because slots provide a context in which habitual bouts of mind-wandering are reined in by the attention-capturing sights and sounds of the machine.