Bonus is a special feature of the particular game theme, which is activated when certain symbols appear in a winning combination. The player can choose from several items shown on a screen. As the player chooses items, a number of credits is revealed and awarded. A mechanical device, such as a spinning wheel is used by some bonuses. It works in conjunction with the bonus to display the amount won.
A light on top of the slot machine is Candle. It flashes to alert the operator that change is needed, hand pay is requested or a potential problem with the machine.
Carousel refers to a grouping of slot machines, usually in a circle or oval formation.
A container where the coins that are immediately available for payouts are held is coin hopper. It is used to rotate coins into the coin tray when a player collects credits. A coin diverter automatically redirects excess coins into a drop bucket, or drop box when a certain preset coin capacity is reached.
Credit meter is used for displaying the amount of money or credits on the machine.
There is a container located in a slot machine's base that is used to divert excess coins. A drop bucket can usually be found in low denomination slot machines. A drop box can be found in high denomination slot machines. There is a hinged lid with one or more locks in a drop box and there ais no such lid in a drop bucket. The contents of drop buckets and drop boxes are collected and counted by the casino on a scheduled basis.
Electronic Gaming Machine is called EGM.
Hand pay refers to a payout made by a slot attendant or cage, rather than the slot machine. When the amount of the payout exceeds the maximum amount that was preset by the slot machine's operator a hand pay occurs. Usually, the maximum amount is set at the level where the operator must begin to deduct taxes. A hand pay could also be necessary as a result of a short pay.
There is Hopper fill used to record the replenishments of the coin in the coin hopper after it becomes depleted as a result of making payouts to players. The slip indicates the amount of coins placed into the hoppers, the signatures of the employees involved in the transaction, the slot machine number and the location and the date.
A stool is included into Low Level or Slant Top slot machines, so you can sit and play. Stand Up or Upright slot machines are played while standing.
The term Optimal play is used to denote a payback percentage based on a gambler using the optimal strategy in a skill-based slot machine game.
A straight or zigzagged line that crosses through one symbol on each reel, along which a winning combination is evaluated is called Payline. Classic spinning reel machines usually have up to nine pay lines, while video slot machines may have as many as one hundred.
While the meters count up to the amount that has been won the process of dramatizing a win by playing sounds happens which is called Rollup.
Short pay refers to a partial payout made by a slot machine, which is less than the amount due to the player. It can happen if the coin hopper has been depleted as a result of making earlier payouts to players. In this case the remaining amount will be paid as a hand pay or an attendant will come and re-fill the machine.
The term Theoretical Hold Worksheet. Is used to denote a document provided by the manufacturer for all slot machines. The theoretical percentage that the slot machine should hold based on adequate levels of coin-in is idicated in it. The reel strip settings, number of coins that may be played, the payout schedule, the number of reels and other information is indicated in the worksheet.
Weight count is an American term, referring to the dollar amount of coins or tokens removed from a slot machine's drop bucket or drop box and counted by the casino's hard count team through the use of a weigh scale.

There exist at least two types of slot players.
Persistent player.
The players of this type believe that very soon there will be a period when the machine begins to pay. Just a second and the coins will be flying all over the casino!
The player will play until the machine pays out. He must have found a machine that haven’t paid for a long period of time or he has inserted to many coins and has got nothing. They believe that at least any payout is due to happen. They can’t leave the machine because as soon as they do it will burst forth and pay out large sums. Maybe it can really work if you have already spent thousands of dollars and have got nothing back. The machine will pay any way.
Many years ago players have their own way of determining whether the machine has not paid out for a long period of time. They touch the coins to see whether they were cold or hot. If the coins were hot they believed that the machine had not paid for a long period of time. In fact the coins could be hot only because of the numerous lights that heated the coins.
The second type of slot players is a chaser.
The player thinks that the machine he is going to play is not a machine that never pays. One can feel the atmosphere of comfort and trust between the machine and the player.

United States
In the United States the availability of slot machines is highly regulated by state governments. Many states have established gaming control boards to regulate the possession and use of slot machines. Nevada is the only state that has no significant restrictions against slot machines. In New Jersey slot machines are allowed only in hotel casinos operated in Atlantic City. Several states allow slot machines only on licensed riverboats or permanently-anchored barges. Delaware allows slot machines at three horse tracks. They are regulated by the state lottery commission.

Native American Casinos
Native American casinos located in reservations are not permitted to have slot machines. It is permitted when the tribe first reaches a pact with the state in which it is located. Typically, a pact entitles the state to receive a fraction of the gross revenue from slot machines.

Slot Machine Classes
There is no federal law governing slot machines. Their classifications may vary from state to state. Some states have restrictions on the type of slot machines that can be used in a casino or other gaming area. "Class III" (or "traditional") slot machines operate independently from a centralized computer system. A player's chance of winning any payout is the same with every play. Class III slots are most often seen in Nevada or Atlantic City. They are sometimes referred to as "Vegas-style slots".
"Class II" slot machines ("video lottery terminals" or "VLTs") are connected to a centralized computer system. It determines the outcome of each wager. Each machine has an equal chance of winning a series of limited prizes. The casino pays a fee to the state for each Class III game. Class II games are not so tightly regulated by the state.

Class II Game Characteristics
The player is playing against other players. They are competing for a common prize. There is necessarily a winner in each game. The game continues until there is a winner. In a given set there is a certain number of wins and losses. Once a certain combination has occurred it cannot occur again until a new batch is initiated. One game is dependent on previous games. The player must be an active participant. All players play from the same set of numbers as the numbers are announced.

Class III Game Characteristics
The player is playing against the house. Each game is independent of previous games. Any possible outcome can occur in any game.

Slot Clubs
Many American casinos offer free memberships in "slot clubs". They return a small fraction of the amount of money that is bet in the form of comps (complimentary food, drinks, hotel rooms, or merchandise). These clubs require that players use cards to insert into the slot machines. Comps or "cash back" from these clubs can make significant differences in the maximum theoretical returns.

Australia
Queen of the Nile (manufactured by Aristocrat) is one of the most popular Australian poker machine games. Slot machines in Australia are officially termed Gaming Machines. Australian-style gaming machines frequently use video displays to simulate physical reels. There are usually five of them. The laws regulating the use of gaming machines in Australia are a matter for State governments.
Gaming machines are found in casinos as well as pubs and clubs in some states. The first Australian state to legalize this style of gambling was New South Wales. In 1956 they were made legal in all registered clubs in the state.
Western Australia only permits the use of particular forms of gaming machine.

United Kingdom
Row of old fruit machines are usually known as fruit machines, one-armed bandits and AWP in Britain. Fruit machines are commonly found in pubs, clubs, arcades, and some take-away food shops. These machines commonly have 3, but can be found with 4 or 6 reels with around 16 or 24 fruit symbols printed around them. These reels are spun. If certain combinations of fruit appear, winnings are paid from the machine. These are very similar to slot machines seen in casinos and elsewhere around the world. These games have lots of extra features. However, the jackpots from these fruit machines are strictly limited. Fruit machines in the UK also almost universally have the following features. A player may be given the opportunity to hold one or more reels before spinning. This can sometimes increase the chance of winning. A player may also be given a finite number nudges following a spin. A nudge is a single-step rotation of a reel of the player's choice.
The maximum payout for an individual game depends on the type and the location of the machine. Private members' clubs are allowed "club machines". They have higher jackpots and are allowed to charge more per game.
These machines also operate in a different manner to American slot machines. The probability of getting the jackpot in each game is independent of any other game.
The AWP fruit machine is popular across Europe and in countries such as the Czech Republic, Russia, and Ukraine.

Japan
Japanese slot machines are known as pachisuro. They are a descendant of the traditional Japanese pachinko game. Slot machines are a fairly new phenomenon. They can be found in mostly in pachinko parlors and the adult sections of amusement arcades, known as game centers.
The machines are regulated with IC chips. They have six different levels changing the odds of a "777". Despite the many varieties of the machines, there are certain rules and regulations.