Slots are the most popular form of gambling, accounting for about 60 percent of all casino profits. Unlike table games such as blackjack or craps, they don’t require any skill and can be played by nearly anyone who can press a button and pull a handle. The popularity of slots owes to their ability to combine engineering acumen, mathematical know-how, and psychological deceit. This unique combination of elements creates a mystical attraction that continues to thrive in today’s digital world.
Originally, casinos installed slot machines as a way to entertain casual gamers and draw in new customers. The machines don’t require any prior gambling knowledge, and the minimum bet is relatively small. The machines quickly became a mainstay at casinos, and they have since grown to become one of the most profitable forms of casino entertainment.
The mechanical parts of a slot machine are complex, but their operation is relatively simple. The reels are lined with varying symbols, and winning combinations are determined by how many of these symbols line up when the spinning reels stop. The symbols vary by machine, but are typically stars, card suits, bars, and various pictured fruits (cherries, plums, and oranges are common).
In 1963, Bally Manufacturing Company introduced the first electronic slot machine. Electromechanical sensors replaced the mechanical switches and wires, allowing for a wide range of features. For example, the machine could now pay out on diagonal matchups as well as horizontal ones, and it was able to accept multiple coins for larger payouts. Later, Herbert S. Mills pioneered the inclusion of a pack of gum with every play, in order to skirt laws restricting slot use.