How do Classic Slots work? Slot machines use a so-called Random Number Generator (RNG). This RNG decides which symbols are shown on superslot pgslot your screen. The RNG system is tested and checked by online gambling regulators and commissions. This system is 100% reliable and fair. Old mechanic slots had 3 reels and on these reels there where only a few symbols. These reels can only have a limited number of combinations. Payous on these older machines are not as high as the payouts on the newer classic slots. New classic slots show symbols on a machine/ screen. They are not actually on a real reel. Because of this these classic slots have more possible combinations. And payouts are higher on these games.