What Is a Slot Machine?

A slot machine, also known as a fruit machine or a one-armed bandit, is a casino game where players pull levers or use buttons to try to win prizes. The machines typically have three or more reels, which spin to display symbols. The winning combinations are determined by matching symbols on adjacent reels.


The most common symbols used in slot machines are bars, lucky 7s and Liberty Bells. However, newer machines offer a wide variety of themes and symbols. Some of these symbols can even act as wilds, forming a winning combination when they appear on multiple reels.


The pay table of a slot machine shows the symbols that can be won, their multipliers and how much money you will win for matching them. It is usually located on the face of the machine or in a dedicated help menu. It will include a list of the paylines and other features.

Reel slots

The earliest slot machines were mechanical revolving reels that were set up in rows of five. While these reels provided a greater number of possible combinations, they were also less reliable than modern video slot machines. In addition, they were limited in size and jackpot sizes.

Multi-line slots

Since the 1990s, most traditional three-reel slot machines have been replaced by multi-line games, which have more than one payline. Depending on the type of machine, this may be as few as one or as many as 10, 15, 25 or more paylines.

Some slots have a fixed payout value per line, while others are based on the number of coins placed on each payline. In both cases, the player’s chances of winning are improved by placing a higher wager.

Bonus rounds

The majority of slot machines have a bonus round feature where players can get a number of free spins or other prizes. These prizes can be as simple as extra credits or as complex as a random win multiplier sequence or a jackpot feature. The amount of money that can be won during a bonus round is often listed on the pay table.

Multi-line slots

Some modern slots have more than one payline, with a maximum of 117,649 possible ways to win. These machines can be found in casinos and are popular with high rollers.

A machine with a fixed paytable is called a classic slot or fruit machine, while those with a progressive jackpot are often called video slots. These games allow a greater range of bets than classic machines and can have more exciting graphics, sound effects, and special features.


It has been said that slot machines must have some sort of computer program at work to stop a player from winning over and over again. Whether or not this is true is up for debate, but it is certainly an interesting theory.

In many states, slot machines are regulated by the state lottery commission. In New Jersey, for example, a person cannot own or operate a slot machine without obtaining a license from the state.