A slot is a position in a sequence, grouping, or set. A slot can also refer to a place in an aircraft or spacecraft. It may also refer to a space or time reserved for an operation, especially one that is scheduled in advance. The word slot has several meanings in English, and its usage is derived from a root word that means to fasten or shut. The first sense of the word was used in the early 14th century as a noun, meaning a bolt or bar for fastening something, such as a door or window. It later came to mean a hole for passing something through, such as a rod or wire. The verb form, to slot, was first recorded in the mid-19th century, and it meant to place or set something into a corresponding slot.

The term slot is also used in computer programming, where it refers to a position or value in a program. A computer programmer can use a number to represent a particular slot, and the function that executes that slot will be executed at that point in the program. The term slots has also been extended to refer to a group of related operations or programs, such as a set of algorithms for solving a problem.

In a slot machine, the symbol combinations and pay table determine how much the player earns for winning a spin. The symbols vary from game to game, but classics include fruits and stylized lucky sevens. Some slots also feature special icons that are aligned with the theme of the game. The pay tables are displayed on the face of the machine, above and below the reels, or within a help menu on video machines.

A bonus round is a feature that is added to a slot machine in order to entertain the player and boost the amount of coins or credits he or she wins. These features may take the form of additional reels, a different type of spinning wheel, or interactive mini-games. Some bonuses are triggered randomly, while others require the player to select items or enter a code.

An airport slot is a permission granted by a traffic manager for an airline to land or depart at a congested airport at a specific time. The use of these slots has resulted in huge savings for airlines and the air traffic control system, in terms of both delays and fuel burn. In addition, the use of slots has allowed the introduction of more efficient flight paths, which have led to increased capacity and a more environmentally friendly aviation system.