In computing, a slot is a position in the memory or disk where a certain type of object can be stored. The word is also used to refer to a specific place on a motherboard where expansion slots for ISA, PCI or AGP cards can be installed.
In the past, slot machines were mostly tall, noisy boxes decorated with images of pigs and pirates. They were popular attractions in saloons, especially if they paid out a few coins for a lucky spin. But the popularity of these gambling machines prompted morality, clergy and then the law to restrict their use. Fey developed a machine that accepted paper tickets rather than coins. This allowed purchase and payout to be made surreptitiously across a saloon bar counter, skirting laws against their operation.
By the 1920s, Fey’s machines were in widespread use. His improvements in reliability, cost and a new display that showed the total amount of money paid out made them even more popular. He even developed a “taste” system that would pay out small amounts to keep gamblers betting. This was a precursor to today’s video game systems that reward players with free spins and other bonuses for continuing to play.
A modern slot machine is controlled by a random number generator (RNG). The computer uses an algorithm that cycles thousands of numbers every second to select the stops on the reels. The reels appear to rotate as a courtesy to the player because the RNG has already selected them.