A slot is an opening into which something can fit, such as a coin into a slot machine. The term may also refer to a position in a series, sequence or list. It can also refer to a position on a team, especially in football, where slot receivers run routes that correspond with other receivers and are closer to the ball carrier.

Air Traffic Management slots are time allocations issued by EUROCONTROL as part of its capacity and flow management role. These are used at airports where the number of planes is constrained by runway throughput or parking space (such as a number of Greek island airports) and allow airlines to operate at certain times when the air traffic system is less busy. Airlines that have been allocated a slot can avoid delays and unnecessarily burning fuel by staying on the ground or taking off when their slot arrives.

Penny slots are low limit machines that offer a high percentage payout over time. They can be found in a variety of casinos and online gambling sites, and are suitable for players with a limited budget. Quarter slots are a close relative of penny slots, offering a similar pay table but a higher denomination. These slots are popular among players who are looking for a more lucrative experience without the risk of losing too much money. They are also easy to find at both online and land-based casinos. Some slots allow you to choose how many paylines you want to activate while others are fixed and cannot be changed.