Larger casinos offer slot machines with denominations from $.01 (penny slots) all the way up to $100.00 or more per credit. Large denomination slot machines are usually cordoned off from the rest of the casino into a "High Limit" area, often with a separate team of hosts to cater to the needs of the high-rollers who play there.
Slot machines common in casinos at this time are more complicated. Most allow players to accept their winnings as credits, which may be "spent" on additional spins.
In the last few years, new slot machines commonly known as "multi-denomination" have been introduced. In a multi-denomination slot machine, the player can choose the value of each credit wagered from a list of options. Based upon the player's selection, the slot machine automatically calculates the number of credits the player receives in exchange for the cash inserted and displays the amount of available credits to the player. For example, a player could choose to wager one dollar per game on a nickel slot machine. This eliminates the need for a player to find a specific denomination of a particular slot machine; they can concentrate on simply finding the machine and setting the denomination once they decide to play.
Recently, some casinos have chosen to take advantage of a concept commonly known as "tokenization," where one token buys more than one credit. A casino can configure slot machines of numerous different denominations to accept the same type of token. For example, all penny, nickel, quarter, and dollar slot machines could be configured to accept dollar tokens. This significantly reduces a casino's inventory costs and coin handling costs. A tokenized slot machine automatically calculates the number of credits the player receives in exchange for the token inserted and displays the amount of available credits to the player. When a player chooses to collect his credits (by pressing a "Cash Out" button), the slot machine will automatically divide the number of credits on the credit meter by the value of one token and return the result to the patron. Any remainder is known as "residual credits" and cannot be collected. Residual credits must be either played or abandoned.
In 1887, a strange mechanical behemoth came into existence. Weighing over one hundred pounds, this metal monster was, essentially, a gambling machine. It was called the Liberty Bell, and was built by Charles Fey in his basement in San Francisco. An improvement upon earlier attempts, the Liberty Bell consisted of three metal reels, each containing ten spaces for symbols. Fey used symbols like stars, diamonds, spades, hearts, and the Liberty Bell- hence the name. When a lever on the side of the machine was pulled, the metal reels would each spin independently of each other, causing the symbols to flash by in a display located on the front of the machine. If three symbols lined up correctly, the machine would dispense a payout- up to a jackpot of fifty cents.
This gambling device was a huge success - so much so that Fey could not meet the demand for his product. By 1907, other major companies were manufacturing similar devices, though many were for regular vending purposes. The Bell Fruit and Gum Company built a machine that issued sticks of flavored gum if the three reels were lined up on their machine. They used fruit symbols: cherries, melons, bananas, and so on. In fact, one of their very earliest company logos was the BAR symbol. These symbols, and the ones created by Charles Fey, prevail today in even the most modern slot machines.
Around 1910, the American public began to take on an exceptionally dim view of gambling. Therefore, and occurring within a very short period of time, slot machines were largely banned in the United States. However, the public had developed a taste for the machines, and it was not long until the ban was lifted.
In 1975, the first electronic slot machine was introduced to casinos. These slot machines utilized a computer chip to control the game, and offered not only a more tightly controlled method of gambling from the casino’s standpoint, but also offered more consistency and fairness for players. For these reasons, electronic versions of slot machines have become so popular that today they account for the vast majority of income for nearly all casinos.