The Science Behind Game Machines: Understanding RTP, RNG, Symbols & Game Limits

Feeling tempted to test your luck at virtual slot machines? Before you start chasing those jackpots, you need to grasp the mechanics behind slots. 

Return To Player (RTP)

Return to Player (RTP) is the percentage a slot machine will “return” to you for stakes placed. Heads-up: it’s an average rather than a guaranteed value. And it’s only valid in the long term after many spins have been made.

A quick example for you. Say, a slot game has an RTP of 95%. It’ll pay out $95 for every $100 in the long run. The other $5 is owned by the casino and is termed “the house edge”. The house edge decreases when the RTP increases. 

Before playing a game, check that RTP figure. That will help you assess if you could stay profitable over the long haul. But again, that’s not a guarantee of wins. 

Random Number Generator (RNG)

A key feature of slot machines is that they give random results every time. This is possible because of a Random Number Generator (RNG). That’s an algorithm created using a small computer chip and some code. It outputs numbers without a pattern, making every spin fair and random.

There are generally two types of random number generators: 

• Pseudo-random number generators (PRNGs) — these use a starting number and math formulas to create random-like results.
• True number-to-person generators — these rely on real-world events, like electrical noise, to create completely random numbers.

Slot machines rely on PRNGs, which take a small starting number to generate long sequences of numbers. The machine then uses these sequences to produce random results for each spin.

A tip for players: check if a casino has its RNG certified by testing labs like eCOGRA or iTech Labs. These certificates verify that RNGs function properly.

Symbols 

Different slot games have their unique symbols, depending on their theme.  There are four general types you will encounter:

• Standard slot icons
• Wild symbols
• Scatter symbols
• Bonus symbols

To get familiar with those, just launch a few slot titles at Casino Adrenaline Online. You can play for fun (without registering an account) or with bonus free spins (to be able to win real money).

Standard Icons

Standard symbols usually occupy most positions on the reels. Usually, they vary from one game to another. 

Old-school players remember slot machines mostly using images of fruits. Card ranks and card suits were also popular. Modern slot games? Those have all sorts of colorful symbols, often matching a particular theme:

• Adventure-themed games feature treasure chests, ancient landmarks, and explorers. 
• In wildlife-related slots, you’ll see plants and animals.

Wild symbol

A wild symbol is similar to the wild card in poker. It can stand in place for any standard symbol on the reels to generate a winning combination. 

Let’s assume that you need four identical icons to win. If you have three identical symbols and a wild, the wild will serve as the fourth matching symbol. Then you win. 

In some games, a wild symbol can trigger a bonus round or be a multiplier. When it’s part of a winning combo, it can boost your payout enormously. 

Scatter symbol

A scatter symbol can trigger free spins or bonuses. It doesn’t have to align on any particular pay line to generate a reward. You just need to land a certain number of scatter symbols. They don’t have to be in any specific order.

Bonus symbol

Bonus symbols are the rare icons that activate free spins or special prizes. Wager large amounts per spin? Chances are, you’ll see bonus symbols frequently. 

Depending on the game, you’ll need three or more bonus symbols in one spin to activate the bonus features.

Variance

Next, slot machines differ in their variance. It’s a measure of the size and frequency of a game’s payout. Here’s a rundown:

• Low-variance slot games tend to pay out small amounts in a persistent pattern. 
• In high-variance ones, you’ll likely win a large payout within longer intervals while playing.

Want to stretch your bankroll for longer? Then go for a low-variance slot. But, if you don’t mind higher risks, high variance might work better for you.

Bet limits 

Finally, we have bet limits — the lowest and highest amount you can stake per spin. Physical slot machines have these figures on their info panel. For a virtual slot, check the game settings.

If you’re a casual bettor, you’ll want to look for machines with lower bet limits. If you’re into high-stakes play, go for games with higher bet limits to fit your larger wagers.

Final Thoughts

I hope this guide has demystified the science of slots for you. These games work based on math and probability. Their reward potential can be huge, but you should choose wisely.