Bankroll is the amount of money you have designated for gambling. Keeping your bankroll separate from your personal finances is a good way to avoid gambling problems. There is a bet max button on every slot machine. Bet Max button allows you to play with the maximum bet on this very slot machine. If you have been playing one and the same slot machine for some period of time, you will be rewarded with casino comps. With these comps you can get free meals or even cash in some casinos. The percentage amount of the house edge indicates how much the casino wins from every bet over a long period of time. Payback is percentage amount of each bet dollar, that is paid back. If you play the slot machine with 86% payback it means that it pays back 86% and 14% is the house edge. Remember that these amounts are taken over a long period of time.