What is a Slot?


A slit or other narrow opening, especially one for receiving something, as a coin or a letter. Also: a position in a group, sequence, or series; an assignment or job opening. American Heritage(r) Dictionary of the English Language, Fifth Edition. Copyright 2016 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

A slot is a small opening in a machine that accepts coins or paper tickets with barcodes, allowing the operator to deposit and withdraw funds. The slots are usually arranged in rows and columns, with a lever or button to operate them. The slots may have a fixed amount of money or they may have variable payout amounts based on the number of winning combinations.

Slot is also the name of a feature in computer hardware that provides control over the timing and order of operations in a multiprocessor system. In general, the term slot refers to a portion of an execution pipeline, but in very long instruction word (VLIW) computers it also applies to a subset of instructions that share resources.

For example, an airline flight can be delayed when the plane’s departure is delayed due to an unplanned problem such as weather or congestion at another airport. Air traffic management systems use slots to assign time periods when an aircraft is allowed to take off. This reduces delays and fuel burn, and it is also environmentally friendly. Moreover, the airlines get paid for every minute they don’t have to spend in the air and waiting to land.