How Slot Machines Work

Although slot machines are extremely easy to play the actual mechanics of how they work is pretty complicated and involves tons of technology.  In this article we'll discuss how slots work including an overview as well as modern technologies that are rapidly improving the stability and functionality of slots.  The most traditional layout of slot machines is in the reel format so for all purposes we will use a reel machine in this article. For those of you who are unfamiliar, a reel machine is a slot with 3 spinning reels and different symbols on each reel.  The player wins when 3 matching symbols hit across the payline, which is mapped out on the payout table on the machine.

In most modern slot machines, the player will always have a choice of placing a minimum to maximum bet on the machine, for example on a $1 slot machine players could usually bet between $1 to $3 per spin.  The pay table on the slot machine will show which combinations pay what according to your bet and in almost all circumstances you should be betting the maximum coins allowed since jackpots are usually only paid on maximum coin bettors.

How Slots Work

Contrary to popular belief, slot machines are completely random and each spin is totally separate from the next so things such as streaks or "feeling" that a machine might pay out soon are simply not true.  This is because they utilize what's called a random number generator to assist in determining the results of each game.  A random number generator is a computer program which is constantly selecting numbers from 0 to millions each and every second to ensure that every number selected is entirely random.  Using this data, slot machines are able to ensure that all spins will be independent from each other thus ensuring a fair game that is very difficult to manipulate.

The introduction on random number generators to slots technology was a huge improvement for the machines which historically relied on a series of gears and levers to function.  On the very old machines, the outcome of each game was determined by various weight systems which combined with notches in the gears on the machines would determine the outcome of each round of betting.  As time when on, this method started to become increasingly vulnerable to casino cheats who built devices that could rig the machine and make it pay out on command.  Because of this and other concerns over the general stability of slot machines a great deal of effort was put into developing both stable, secure and profitable slot machines.  Below we've provided an overview of how a typical slot machine game would run with modern technologies.

The basic way that a slot machine works is by using a random number generator in conjunction with a computer program to determine how each reel will land during a spin.  As soon as the player presses spin or pulls the lever on the slot machine, the outcome of that game is already determined by combining the random numbers taken from the generator with various stop combinations programmed into the machine.  Each number is associated with a different stopper on each reel so in a 3 reel machine 3 random numbers would be selected which when compared to the stoppage table would result in three different positions that the reels would land on for a given spin.  This data is then fed into the machine and the reels stop according to their respective positions.

The exact way that the random number generator works with the stoppage tables to determine the result of each game is a closely guarded secret by most slot manufacturers, however we'll provide a brief overview of the general way that it is believed to work.  Basically what happens is that right after you spin the reels three numbers are chosen from random number generator, let's say those numbers were 35, 103 and 77.  Using those numbers a microchip within the slot machine will usually run them through a formula that divides the numbers to give a smaller series of numbers that corresponds to certain stopping points on each reel.  Each stopping point on the reel will either have a blank or a symbol associated with it, so once the stoppage points have been determined they will be displayed to the player.  If the reels stop at a position which results in a prize according to the payout chart, the player will be paid accordingly for that round, if not the player will not win anything that round.