A slot is a narrow opening or groove. The word may also refer to:

A video slot is a casino game that works with a central computer system and multiple screens. Unlike mechanical slots, video slots have reels that spin and symbols that appear on the screen when a winning combination is made. Some video slots feature bonus games and other special features.

In addition to the main screen, video slots have a credit meter that displays the player’s current balance. They also have a button that allows the player to cash out and a jackpot light that glows when a winning combination is made. Some slot machines also have a “service” or help button that flashes to indicate that the machine needs a change, a payout is requested, or a problem has been found.

In the past, all slot machines used revolving mechanical reels to display and determine results. These were complicated and prone to error, and only allowed for a cubic number of combinations, which limited jackpot sizes. The advent of electromechanical technology in the 1960s saw the replacement of the reels with electronic circuitry. The first commercially successful electronic slot machine was Bally’s Money Honey, which featured a bottomless hopper and automatic payouts without the need for an attendant. The machine’s popularity led to its widespread use, and the side lever soon became vestigial. In Canada, slot machines are legal in some jurisdictions, but are generally not regulated by the federal government.