Modern casino one armed bandits are controlled by computer software, and the winner percentages are pre-programmed into the software.
Casino slot machine games have RNGs which are continually generating combinations, even when the machine is not currently being played.
Running synchronously with the random # generator of the casino one-armed bandit is the pay out rate percent.
The pay out percent controls how much the slot machine game will payout, for example the payout per cent may be ninety per cent, which means the slot machine will payout 90% of all the bets played, and the casino simply gets to keep 10 per cent.
This does not mean that each and every time you bet 10 credits you will receive 9 in return – where is the fun and fascination in that? Instead, the casino slot machine game will not payout for a little while, and then suddenly fire up a hot streak and you might draw the big top prize.
The pay out %s most likely will vary between the different games and a handful of the very common casinos, e.g. Golden Online Casino, which puts forth a payment of up to ninety five %!
Thus, in essence, the slot machine game takes all the cash played into it and pays it out to a handful of lucky winners. The casino only gets to keep a averagely low percent of all the plays made.
The casino slot machine software controls every single part of the machine, from the flickering lights to the revolving of the reels.
When you hit spin on the one-armed bandit, a combination is generated by the RNG which associates with the pictures on the reel.