What Is a Slot?


A narrow, elongated depression, notch, or opening for receiving or admitting something, such as a coin or letter. In computer technology, a slot is a position within a pipeline into which an operation can be issued; it comprises the operation issue and data path machinery surrounding a set of one or more execution units that share these resources. The term is most commonly applied to microprocessors, but it can also refer to expansion slots on a motherboard such as an ISA (industry standard architecture), PCI, or AGP slot.

In a slot machine, a player inserts cash or, in the case of “ticket-in, ticket-out” machines, a paper ticket with a barcode into a designated slot on the machine to activate it. The machine then spins and stops the reels to rearrange the symbols, and if the resulting combination matches a pay table entry the player receives credits based on the payout schedule. Bonus features, such as free spins, pick-style games, sticky wilds, and re-spins, may also be included.

The pay table of a slot displays the regular symbols, the payouts for landing them in a winning sequence, and any special rules that apply to the game. Depending on the type of slot, these rules can vary considerably, from a short list to an extensive set of guidelines.