The first slot machines were invented over one hundred years ago, long before computers came along. They were mechanical devices featuring an array of drums. On the drums were various symbols. When a lever was pulled, the drums spun around, coming to a random stop. If the symbols matched up, you won. If not, you lost. Figuring out your odds of winning the big prize was as simple as multiplying the number of symbols on each drum together. Not anymore…
Since the dawn of computer technology, these games have been programmed to defy traditional odds. There are no drums. The number of symbols per reel is not static. Everything is controlled by a computer chip running a software program, designed to pay out a very specific percentage of its take.
The three main programmable functions of a slot machine are the random number generator (RNG), the return to player (RTP), and the volatility. Let’s take a closer look…
Random Number Generator (RNG)
Remember the movie, The Matrix, when the green numbers kept raining down the computer screen? That’s an RNG. It’s a random strain of seemingly endless numbers generated by a computer. The algorithm it generates determines an outcome. There are countless applications for an RNG in the real world, but few so famous as casinos games.
In a slot machine, the RNG determines exactly what symbols will land in each position on the reels. If you could see the RNG, you would never be able to read it. Each and every number in the sequence is changing with each passing nanosecond. It does not stop until the exact moment a player presses the SPIN button. At that very moment, the sequence of symbols is determined by the number produced. As a player, we still see the reels spinning as they come to a slow halt, but the machine already knows where they are going to land, because the RNG told it so.
The whole purpose of the RNG is to ensure no one – not the players, the casino managers, or the players – is able to predict what will happen on any given spin. It’s all about timing. Press at just the right moment, and the jackpot is awarded. For this reason, a machine could pay back-to-back jackpots just as easily as withholding the jackpot for more than a year.
Knowing that this is how a game works, it’s hard to imagine that anyone could know how to predict when a slot machine will win. And yet, so many seem capable of doing so. More on that in a moment…
Return to Player (RTP)
The RTP is the amount of money a machine pays out, compared to what it takes in. The RTP is always displayed as a percentage. For those of you familiar with how “house edge” works, the RTP is the opposite of the house edge. RTP refers to the amount players win back, whereas house edge is the amount the casino wins. Put them together, and you get a total 100%.
For example, let’s say a slot machine has a 95% RTP. This means the game will pay back 95% of its monetary intake over time. The other 5% is the amount the casino wins. Theoretically, if you were to spin the reels 100 times on this machine at $1 per spin, you would end up with $95 left. The important word here, however, is “theoretically”.
RTP is always theoretical. Yes, the machine will meet its RTP. It’s a computer. They don’t make mistakes. But the RTP will only be met over a very long period of time. We’re talking 20-25 years. So no, you’re not going to win exactly $95 back and lose $5 for every $100 you wager. If that were the case, every player would lose and no one would ever want to come back to the casino. That’s where volatility comes in…
A game’s volatility determines how often it is likely to strike a winning combination, and the average size of each prize paid. It can be low, medium, or high. A low volatility game is one that pays out very small amounts very often. A high volatility game will pay high prizes, but not very frequently. And a medium volatility is a balanced game, where mid-sized payouts occur on a regular, but not too regular, basis.
The volatility of a machine will not alter its RTP. Over time, they all perform equally. But in the short term, their attributes can seem very different. At low volatility, a machine will arrive at its intended RTP more frequently, whereas a high volatility game will have much greater upswings and downswings.
Low Volatility = Lower Risk, Lower Chance of a Big Payout
High Volatility = Higher Risk, Higher Chance of Big Payout