A narrow opening, especially one for receiving something, as a coin or a letter. Also used figuratively: a position, assignment, or job opening.

A slot in a computer program or a slot in a schedule is a time when an activity can take place. For example, a visitor might book a time slot a week or more in advance.

In air traffic coordination, a slot is an authorization to fly at particular times at a congested airport. Airlines can use these slots to avoid delays caused by too many planes trying to take off or land at the same time. The slots are granted by EUROCONTROL as part of its network management role. Slots can be traded or sold, and some are very valuable.

When a slot is lit on a machine, it means that change is needed or that the machine has an issue that needs to be addressed. It may also indicate that the machine has a jackpot that is ready to be awarded or that it has reached a bonus game.

The symbol on a slot machine is aligned with the theme of the game. For example, a classic slot might have fruit, bells and stylized lucky sevens, while a video slot might feature characters or locations from a movie. In addition, many slots have a random number generator (RNG), which is used to determine the outcome of a spin. This algorithm is independently verified by external companies and is continuously monitored for security.