Modern casino slots are controlled by computer chips and software, and the win percentages are preprogrammed in to the software.

Casino slots have Random Number Generators (RNG) that are continually generating combinations, regardless of whether the machine is not being played.

Running concurrently with the RNG of the casino slot machine will be the payout percentage.

The payout percentage controls the amount the slot machine will payout, for example the payout percentage may very well be 90%, meaning the slot game will payout 90% of all the bets played and the casino only gets to keep 10%.

This isn't to claim that every time you bet 10 credits you will get 9 in return - where will be the fun and excitement in that? Instead the excellent online casino slot slot machine game will not pay out for a while, and then suddenly go on a hot streak and you might hit a big jackpot.

So in essence the slot machine takes all of the money played into it and pays it out to few lucky winners. The casino only gets to keep a relatively small portion of all of the bets placed.

The casino slot software controls every a division of the machine, from the flashing lights to the spinning of the reels.

Whenever you hit spin on the slot machine, a combination is produced through the RNG which corresponds to the photographs on the reel.