A slot is a small area on the edge of an aircraft wing that allows air to pass over it. Also:
In computer technology, a slot (plural slots) is a place on a device in which circuitry that provides specialized capability can be added. For example, a computer may come with several expansion slots for adding hardware capabilities such as video acceleration or disk drive control.
The term slot is also used to refer to an allocated time and place for an airline’s aircraft to take off or land, as authorized by a flight schedule or air-traffic controller.
Typically, players insert cash or, in ticket-in, ticket-out machines, paper tickets with barcodes into a slot on the machine to activate it. The reels then spin and stop to rearrange the symbols, and the player earns credits based on the paytable. Modern slot machines may use a variety of symbols, ranging from stylized lucky sevens to fruit, and they may have several paylines.
Once a machine is activated, the random number generator (RNG) records a sequence of numbers that corresponds to each stop on the reels. The computer then finds the corresponding reel location and causes the reels to stop at those placements. If the resulting combination of symbols matches one in the paytable, the player wins. Slots with a fixed amount of paylines are sometimes called free slots and those that require a minimum wager to play are often referred to as fixed.