A slot is a narrow opening, often with a slit, through which something can pass. A slot in a door or wall is usually rectangular but can be round, square, or another shape.
Sports An unmarked area in front of the goal between the face-off circles on an ice hockey rink. Also, in Australian rules football and rugby, the slot is the gap between the forwards’ line of defence and the backline.
The term slots has become more generalized in the English language to refer to any kind of narrow opening, especially one for receiving something, such as a coin or a letter. The use of the word slots in this sense began in the 19th century, when it was used in a game of poker called Jacks or Better, in which players contributed an amount to the pot prior to each deal, and a series of hands during which nobody could claim a pair of jacks or higher would increase the size of the jackpot.
In modern slot machines, microprocessors allow manufacturers to assign a different probability to each symbol on each reel. This allows them to give the player the appearance that a particular symbol is close to winning, although the actual chance of getting a specific combination is very low. The pay table for each slot machine lists its winning combinations and the number of credits a player will receive when those symbols appear on a payline. This information is generally listed above and below the reels on older machines, but on video slots it may be contained within a help menu.