What is a Slot?


A slot is a narrow opening in the surface of a thing, especially a machine or instrument, that allows something to pass through. This is often used for a purpose such as holding a key, or in a door or window to hold a handle or crank. It can also refer to an allocated time and place for aircraft to take off or land as authorized by air traffic control. See slat (def 2) and slot (def 3). In ornithology, a slot is a narrow notch or similar opening in the primaries of certain birds.

Slot machine, also known as fruit machines in the UK and pokies in Australia, are the most popular type of casino game. They have a distinctive design and pay out credits when matching symbols appear on a line, or pay-line, on the machine. The payout amount varies depending on how many identical symbols connect in a winning combination. Symbols vary according to the machine’s theme, but classic symbols include fruits and stylized lucky sevens. Some slots also have special symbols that trigger bonus features.

Charles Fey’s invention of a new poker machine in 1887 led to the modern slot. Fey’s machine allowed automatic payouts, had three reels and increased the number of symbols to allow for more combinations. He used diamonds, spades, horseshoes, hearts and liberty bells as the winning symbols. The three aligned liberty bells were the highest win, giving the machine its name—the slot.