Carousel: A group of slot machines.

Free game: available here at Top Casino Offers: free slot machine games

Hopper: This is where the money is stored inside the machine. 

Low Level: Slot machines you can sit at to play.

Payback: The percentage of winnings a machine will payout in relation to the amount put in.

Pay for Play Machines: These are generally one-two-three coins option slot machines with staggered payoffs. The more coins you put the better the payoffs.

Payline: The line at which the symbols must align to win.

Progressive Slots: A group of slot machines called a Carousel linked together to pay one common big jackpot.

Reels: The rotating narrow barrels on which the symbols appear.

Stand Up: Slot machines where you play standing up.

Take/Pay Cycle: Based on the assumption that most slot machines work on cycles, it is when to expect a machine to pay out following a certain amount of coins fed into it.

Tilt: When a machine stops operation, usually following a malfunction.