Slot Machine Terminology

If you are new to playing slot machines, then it is a good idea to become familiar with the following terminology. All the terms will be commonly found throughout this site as well as slot pay tables, casino information or even just in general conversation with other slot players.


All Ways
Refers to games where wins are paid based on symbols on consecutive reels rather than on lines. The most common All Ways format is 243 Ways such as Aristocrats Reel Power games.
Anticipation Spin
Describes the animated slowing down of a reel result. Most commonly seen on video slots when you have one more symbol required for a bonus trigger.


Bonus Feature
Some of the latest slot machine have a special feature that once activated will give you free spins or a bonus round where you will win additional coins. These are highly entertaining.


Cascading Symbols
A video slot bonus style where symbol wins are paid and then these symbols are removed and then replaced by symbols from above.
Class I (USA)
A type of gaming machine used in Tribal gaming with prizes of nominal value and / or part of tribal festivities or ceremonies.
Class II (USA)
A type of gaming machine where results are determined from a virtual bingo game from servers that must be on tribal land. These games may look like regular slots but they work completely differently.
Class III (USA)
A type of gaming machine that is neither Class I nor Class II. These are the slots that you find in Las Vegas and at almost every casino around the world.
Coin In
Also known as handle, coin in refers to the total amount of all wagers on a slot machine.
Coin Size
This set denomination of a slot machine. Common coin sizes include 1c, 2c, 5c, $1, $5, and $10. On most slots you can bet more than one coin per spin.
After you insert money into a slot machine your money is converted into credits based on the machine’s denomination. For example, on a penny machine $1 equals 100 credits.


Double Up
A feature most commonly seen on video slots, the Double Up gives you the opportunity to gamble your win on red or black. This game has no house edge.


Stands for Electronic Gaming Machine and is another term used to describe a video slot machine.
Stands for erasable programmable read-only memory. All game logic for a slot machine is stored in this computer chip which cannot be altered by players or the casino.
Expanding Symbol
A video slot bonus style where one or more symbol can expand to take up more than one symbol position. Most commonly expanding symbols grow vertically although they can also go horizontaly or diagonally.
Extra Bet
An additional bet option on some machines that unlocks some sort of extra bonus such as more free spins or higher frequency of bonuses.


Free Spins
A bonus feature where you win free games. Often includes a multiplier for wins that occur while the free spins are in play.


Hit Frequency
This is the frequency at which winning spins occur. This term is often used with bonus feature slots as the number of spins between the bonus feature being won. A higher hit frequency is better than a low one although you must take the overall volatility as well.
Hold and Spin
A feature style first seen on the Lightning Link series of games from Aristocrat. Hold and Spin bonuses are triggered with a set number of symbols and then you re-spin to collect more symbols.
In land-based slot machines this is where the coins you put in are stored. The hopper can be empty so you should always be sure that you have been paid out the correct amount before playing on. If the number of coins is less than you should have won, call an attendant who will pay you the additional winnings.
House Edge
The theoretical house edge on any slot machine is calculated by the distance the payout percentage is to 100%. For example, a 97% machine gives the casino a 3% house edge (100% - 97% = 3%).


The highest single line / way payout on a slot machine. The jackpot is often listed in the highest position on the pay table.


Max Bet
This is the maximum amount of coins that you can play per spin. It is of the most importance when playing progressive slots because usually the max bet must be played to qualify for the jackpot.
This simply means a slot machine with more than one pay line. Slot machines can have up to 20 different pay lines and it pays to read the machine before you play to avoid any disappointment.
A machine that offers more than one game title in a single cabinet.
A symbol or feature where wins are paid at a multiple of the displayed value. Examples are wild multipliers and free spin multipliers.


Pay Line
This is the line on which you must line up the symbols to score a win. Modern slots can have from 1 to 100’s of pay lines.
Pay Table
The pay table is the section of the slot machine which tells you how much you will win for each type of combination. The pay table will also tell you if there are bonus features and if max bet will reward you with a bonus top prize.
Payout Percentage
The theoretical return that a slot machine will achieve over millions of spins.
Pokies (Australia and NZ)
An Australian term for slot machines believed to have come from abbreviating poker machines.
Progressive Contribution
The percentage amount of each bet on a progressive slot machine that gets added to the jackpot after every spin.
Progressive Jackpot
This is a top prize which grows as people play. Often these machines are linked up at several casinos so the jackpots can grow very large. As always "reading" the machine before you play is a must.


Random Jackpot
A feature where a progressive jackpot can be won on any spin regardless of the symbols on the screen / reels.
Random Number Generator
A computer program that outputs random numbers. The RNG on a slot machine is continuously outputting random numbers which are mapped to reel positions.
A feature where one or more reels are re-spun. Can be a paid re-spin bonus or a free bonus often seen with one scatter symbol required to trigger another feature.
Winning a bonus feature while already on a bonus feature. For example, winning more free spins during a free spins bonus is known as a re-trigger.
The rotating part of the slot machine, the symbols are on the reels. Modern slot machines can have from 3 to 5 reels.
Return to Player
See Payout Percentage


A symbol that pays in any position on the reels (sometimes anywhere left to right only) is a scatter symbol. Commonly used to trigger bonus features.
Stacked Symbol
A symbol on the reels that repeats vertically in stacks.
A term used to describe slot machines that use physical reels instead of a screen.
Sticky Symbol
A video slot bonus feature where a symbol remains in place for another spin or spins.
These are the pictures which you must line up to score a win. Common examples are "BAR" symbols and "7" symbols.


Stands for “Ticket in Ticket out”. In many casinos today all machines print out tickets instead of dropping coins into the tray when you cash out. Tickets can be redeemed for cash at machine or the cashier or inserted into other machine to play with the ticket value.


Describes how frequently a machine pays out wins and the size of the wins. Slots are categorised into levels ranging from Very High to Very Low volatility.


A style of video slot that pays out wins not based on lines but instead on any position on adjacent reels. Common Ways formats include 243 ways and 1024 ways.
Wild Symbol
This acts like a joker and will count for any other symbol, often making up that crucial third symbol in a winning combination. Some slots have wild symbols which also multiply the win for each wild that is present in a combo, these slots are of course very popular.

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