What is a Slot?


You’ve checked in, got through security and queued to get on your flight. Then the captain announces that you will need to wait for a slot. What is a slot, and why can’t the plane take off straight away?

Slots are tall machines with reels that spin and land symbols in a random order. The machine pays out credits if a winning combination appears on the pay table. A modern slot may have five reels or more, but classic ones usually only have three. Each reel has different symbols, and they are aligned to match the theme of the game.

Unlike other casino games, slots use a random number generator to determine the outcome of each spin. The RNG algorithm runs through dozens of numbers per second, and each symbol has its own assigned probability of appearing on a particular reel. Each time a signal is received (from a button being pressed or, in the case of mechanical reels, a handle being pulled), the computer sets a number for that specific position on the virtual reel. When the physical reel lands on that number, it will display the associated symbol to the player.

Slots are popular for their ability to offer impressive jackpots. However, many players are put off by the fact that they can’t predict when they might win. This is because a simple dice roll, for example, has an equal chance of landing on any of the six sides. However, because the probabilities of each symbol occurring on a payline are weighted differently, the odds for winning a particular payout vary between machines.