The presence of microprocessors in slot machines not only made it possible for all the sounds, light and meters in the machine, it also brought about something called the Random Number Generator (RNG), through which the odds could be customized from machine to machine. The RNG cycles through thousands and thousands of combinations of numbers and settles on outcomes randomly.
The reels on the slot machine are programmed to stop at whatever combination the RNG happens to pick at that time.
The RNG enables "virtual" reels as opposed to actual reels. These reels have more virtual "symbols" on them. That adds up to many
more combinations and a much, much greater jackpot possibility for the player.
The RNG, in effect, pre-selects the outcome for each and every spin on the slot machine, making the actual spinning of the reels more of a formality than anything else. Before you have even pushed a button or pulled a handle, the machine knows whether you are going to win or not.
The machines, of course, are programmed to stop at non-paying combinations more often than others. That's how casinos stay in business, and that's something players understand perfectly. But because it is "random," it does allow for a winning combination to appear, and certainly reduces the possibility that the outcomes can be subject to specific manipulation from both internal and external sources.
The results are based on a long-term pay schedule, which means that the casino knows what it is going to be getting out of each machine
on a long-term basis, though the short-term results for the customer are still left pretty much to chance.
In addition to being essential to the development and advancement of slot machines, the RNG is also the governing mechanism behind all player vs. house games that are played over the internet. Naturally, that includes slots, which are, of course, seen but not touched.
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