What’s not to love about slots? With little effort and a whole lotta luck, you could go from rags to riches in the blink of an eye! These fun, super easy to play machines pack a lot of potential to change your life forever. The question is, what’s behind the proverbial curtain? How does a slots machine actually work?

To answer that question, we have to step back in time. The time? The late 19th century. The place? San Francisco, California. After the heady days of the 1849 gold rush, San Francisco had become a boom town. As the 9th largest city in the United States, it was chalk full of taverns, inns and saloons. A place of rest, recreation and good times for miners, cowboys, sailors and working girls alike.

In those days a man named Charles August Fey had set up a small engineering shop in his basement. A German immigrant, Fey was a true tinkerer, the type who loved to build random machines. Now, saloon entertainment in those days, beyond the music and dancing and the odd card game, often consisted of strange mechanical devices, for example a pair of mechanical race horses that would run around a track if a patron inserted a nickel. Often bar keepers would encourage patrons to bet on such novelty races, handing out beer, whiskey or cigars as prizes to keep people entertained.

Fey realized that perhaps there was some real money to be made in such novelties and constructed his own machine. It was a mechanical device consisting of three reels, holding five symbols based on the deck of cards: a diamond, a club, a spade and a heart. He even added the Liberty Bell symbol for fun. The machine was operated by a set of weights and levers at the pull of a wooden or brass arm.

To make a long story short, in no time Fey’s invention was a hit at the local saloon. To such an extent that he opened up a new workshop to manufacture them full time. Of course, in those days gambling was illegal in the US, so it was impossible to patent his new device. Soon copy cats were everywhere, with the most notorious of the lot being the Mills Novelty Company of Chicago. Mills added fruit symbols to the reels. Get three of a particular type of fruit and win a piece of chewing gun with that fruit’s flavor.

Well, this was unfortunate for Fey, as competition quickly over took him on the road to riches, but good for slots lovers. The intensity of the competition led to numerous innovations, with each mechanical machine trying to be better and more entertaining than the last.

By the 1960s, slot machines underwent an even more radical change, with the addition of electromechanical technology. The machines still looked basically the same, with spinning reels activated by the pull of a lever, but the technology allowed casino owners to better control the odds of a player hitting the jackpot and the payouts, making them incredibly profitable. Today in the casino business this tweak of the odds is known as the “house edge” and it’s what makes the casino business go round.

In 1975 the first video slot machine was introduced, employing an entirely different concept, what’s called a random number generator (RNG). Advances in computer technology combined with old mathematics and clever programmers meant that a computer algorithm would determine the outcome of each spin, with each spin being, mathematically, a completely unique event.

The rise of video slots with 5-reel, multiple payline slots, 3D slots and the host of bells and whistles, thrills and spills and endless variations of the thematic spectrum that we see in video slot machines today.


What to keep in mind

Now that said, there are a few important things to keep in mind when it’s time to head to the slots. First, slot machines are the most popular casino games. With today’s slots using RNGs, every single spin is a unique event. In other words, looking for patterns, or thinking that, because a set of spins have come up dry, it’s clearly time for the slot to pay out big are gamblers fallacies. In a nut shell, you have the same odds of striking that jackpot with every spin.

However, different slot machines do pay out at different rates. Casinos can set the house edge for their slots, with payout rates between 84% on the low end up to 98% on the extreme high end.

Moreover, slots with progressive jackpots, machines that keep a percentage of each coin played to put toward a sky’s the limit jackpot, do tend to pay out less often than fixed jackpot machines. The reason should be obvious, progressives have to have the money to put toward the growing jackpot and hence pay out less frequently and often lower amounts on smaller wins.

It’s the jackpot that’s the honey that keeps players coming back, which is why these winnings are hidden high up in the tree.