Modern casino one armed bandits are controlled by computer software, and the winning percentages are pre-programmed into the gaming software.
Casino one armed bandits have Random Number Generators that are endlessly generating combinations, even when the slot machine game is not being played.
Running in unison with the random # generator of the casino slot machine game is the pay out per cent.
The pay out percentage controls just how much the slot machine will payout, for e.g. the pay percent could be ninety per cent, which means the slot game will payout 90% of all the bets played, and the casino simply gets to keep ten percent.
This is not to say that for every time you bet 10 credits you will receive 9 in return – where is the fun and exhilaration in that? Instead, the casino slot will not payout for a while, and then suddenly fire up a hot streak and you might draw the big pot prize.
The profit percentages will vary between the differing games and some of the notably common casinos, for example Golden Online Casino, which tenders a pay out rate of up to ninety five percent!
Therefore, in essence, the one-armed bandit takes all the money played into it and pays it out to a few fortunate winners. The casino only gets to keep a considerably petite % of all the plays allotted.
The casino slot software controls every single part of the machine, from the flickering lights to the rolling of the reels.
When you hit spin on the slot machine, a combination is produced by the RNG which corresponds to the pictures on the reel.