How do Slot Machines Work?

July 8, 2023

You might be surprised to learn that slot machines were somewhat of a casino afterthought. Or, to give that statement some context, the first casino opened in 1639 in Venice, Italy, and the slot machine wasn’t invented until 1894.

You’ve one Charles August Fey to thank for the first modern incarnation of the slot machine, and they were an instant hit. So much so that they were banned in 1909, three years after the first casino opened in Vegas.

By 2010 there were more than 830,000 slot machines in the US, generating about 70 percent of the total casino revenue. But they were facing stiff competition from online casinos offering slots with tantalizing names such as Aztec Millions, Oceans Treasure, and Fishin’ Frenzy.

It’s not hard to see why slots are so popular. They offer all the fun, all the thrill of a casino game without having to do any of the legwork to win. Poker, say, requires rules and tactics. With a slot machine, you pay the money and pull the lever, simple as that.

But how do they work? Let’s go back to Charles Fey to find out.

Early Slot machines

Fey’s original mechanical machines set the blueprint for today’s machines. Take his 1899 machine, The Liberty Bell, which used three reels with symbols on them: horseshoes, playing card suites, and bells, of course.

Just as today, if the symbols lined up, the machine would pay out. Then came the invention of the slot ‘jackpot’ in 1916. Now if the symbols lined up, the slot machine would release all of its coins, and its popularity exploded.

Modern Slot Machines

In the 1950’s, the old mechanical slot machines were given a tweak with electronics. Now a slot machine could regulate pay-outs that would be in proportion to the amount spent.

Video slot machines that displayed symbols instead of mechanical reels arrived in Vegas in 1975. By 1986, all the slot machines in Vegas became remotely linked, allowing punters to win a super jackpot of, in one instance, $40,000,000 in 2003.

Online Slot Machines

Because there are no moving parts, the movement of the reels has to be simulated, this is done by Random Number Generation (RNG) which is an algorithm to ensure fairness.

However, not all RNGs are the same. Hardware RNG (HRNG) generates genuine random numbers, but Pseudo RNG (PRNG) only look random, but in fact, the numbers follow a sequence.

Of course, this is more complicated than an anacronym. Each symbol on a reel is assigned a unique number, so the symbols on the reels are determined by the RNG.

But not all the symbols are equally weighted, meaning you’re more likely to land on a bonus symbol, for example, to keep the gamer involved. And then there is the return to player (RTP) factor to be taken into consideration too.

This is the amount that a machine pays out over a set period. Say the RTP is 95%. This means that for every $100 you put into the machine, the machine will pay out $95.00.

Each machine will have its own RTP number. The higher it is, the better chance you have of winning. And speaking of winning, there are a few little tricks that might help you to even up the odds.

Here are six tips:

  • We’ve already established that the higher the RTP number on a slot machine, the better you have a chance of winning. But how do you determine what that is? Simply by hitting the slot machine’s help button or checking out the game provider’s info page. Anything above 96% is good, so stick to machines with that or preferably more.
  • Check out the ‘pay table.’ Every machine comes with its unique paytable, which shows what each symbol is worth, or if there are any anomalies.
  • Use free games to practice and see what’s going on. If you can’t practice the games you want to play, go online and find them, there’s probably a video.
  • Aim for smaller jackpots. This may seem counter-intuitive if you’re determined to win big, but the odds are better for a smaller win.
  • Remember that you’re playing for fun. Winning money is a bonus, not the game itself. If you’re up for winning money, skill-based casino games like Poker or Blackjack might be more suited to you.
  • Stick to a budget. Slots are fun, but you can easily lose track of time when you’re playing, so have a budget. If you hit your maximum, enjoy the fact you’ve had fun paying for some cool entertainment and go and do something else.

There’s a good reason why slots are surveyed as being both popular and fun, but don’t get carried away without checking our recommendations. So, enjoy your game and always quit while you’re ahead.

You may also like