They are easy to recognize, roaming the aisles for a "kamo" sucker " in English) to leave his machine. However, no operator has ever enacted this strategy. "How slot machines give gamblers the business". Free Spin is a term usedin slot games and online slot games to specify that the spin will be completed without a charge or on the same wager. Usually, landing a number of special symbols on reels is required to activate the free spins bonus round. "Slot Machines: The Big Gamble". Since the turn of the century some information regarding these figures has started to come into the public domain either through various casinos releasing themprimarily this applies to online casinosor through studies by independent gambling authorities. These cheats give the player the impression of an advantage, whereas in reality the payout percentage remains exactly the same. Although the original slot machine used five reels, simpler, and therefore more reliable, three reel machines quickly became the standard.