What is a Slot?

A slot is a narrow opening, especially one for receiving something, such as a coin or a letter. It is also a name for a position or assignment, such as a job or a room on a plane or ship. A slot can also refer to a track or trail, as in the track of a deer. The American Heritage® Dictionary of the English Language, Fifth Edition. Copyright 2016 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

A slots game is a machine that contains rotating reels, each with a set number of symbols that appear in designated positions when a lever or button is pushed. When a winning combination of symbols appears, the player receives a payout, typically a fixed amount of money. A slot machine can also offer special prizes, such as free spins or extra rounds of play, if a specific combination of symbols is triggered.

In the nineteenth century, New York inventors Sittman and Pitt created what was probably the first slot machine. By the time Charles Fey invented his Liberty Bell model in 1899, mechanical technology had improved to the point that a single symbol could occupy several stops on a multiple-reel machine, allowing larger jackpots. Later, microprocessors allowed manufacturers to program each stop to weigh a different probability. This meant that a winning symbol might appear to be “so close” on the physical reel, but it was actually much farther away from the payline than it appeared.