What is a Slot?

A slot is a narrow opening in something that allows something to pass through or fit in. A slot on a calendar or schedule is a time when an event can take place. He was able to slot his schedule around the doctor’s appointment without any problem. The car seat belt slotted easily into place.

A casino slot is a machine that accepts cash or, in the case of “ticket-in, ticket-out” machines, paper tickets with barcodes. The player activates the machine by pushing a lever or button (either physical or on a touchscreen). The reels then spin and, when the stop, they rearrange symbols to form winning combinations according to a paytable. The symbols vary depending on the machine’s theme. Many casino slots have classic symbols, such as fruits and bells, and others may feature characters from popular films, TV shows, comic books, or other pop culture phenomena.

In a computer programming language, a slot is a special member function that follows the normal rules of a member function when called directly but can be invoked from any class, regardless of access level, via a signal-slot connection. This allows developers to write reusable code by using signals to control the invocation of the slot function.

An airport slot is a time when an airline can fly into an air traffic control-approved position to land at a constrained airport, or when the aircraft will be allowed to use an existing runway. The use of slotting has been shown to reduce delays and fuel burn, and it is now used throughout Europe by EUROCONTROL as part of its Flow Management System.