Here are few common slot machine terms:
Bonus - this is a special feature when you get a certain symbols to appear that matching a winning combination.
Candle - It is a light found on top of the slot machines. When there a certain problem on the machine, hand pay request, or a change is need it flashes.
Carousel - this is the grouping of slot machine, where usually machines are grouped in an oval or circle formation.
Coin hopper - this is a container where are coins held when there is an immediate payout.
Credit meter - this is a visual electronic display that shows the total amount of money or credits on a machine.
Drop box or drop bucket - it is a container where excess coins from the hopper are diverted. Low denomination slot machines use drop bucket while high denomination lost machines use a drop box. The casino collects and counts the contents of drop box and drop buckets on a scheduled basis.
EGM - is an Electronic Gaming Machine
Hand pay - rather than being awarded by the slot machines, the slot attendant is the one you makes the payout. This usually occurs when the payout exceeds the maximum amount of the machine.
Hopper fill slip - this is the record of the replenishments of the coins in the hopper after it runs out because of the payouts made. This has the record of the amount of coin placed in the hoppers, time, date, location, slot machine number, and the signature of the employees involved.
Low Level or Slant Top - these slot machines have a stool for you to sit and play unlike in Upright or stand up machines where you play while standing.
Optimal Play - is a payback ratio base on a skill-based slot machine that requires an optimal strategy.
Payline - is a line that crosses through each symbol on each reel, there is a winning combination for it. Video slot machines can have as fifty paylines while classic slot machines usually have only nine paylines. Short pay - this is the partial payout made by the machine. This usually happens when the coin hopper runs out of coins. The remaining amount will be hand pay by a slot attendant or the attendant will have to refill the machine.
Tilt - this is any kind of mechanical problems. Old slot machines usually have this like tilt switches but modern video machines do not have these problems.
Weight count - when tokens or coins are removed from a slot machine the casino count them by using a weigh scale.