Many of us enjoy playing on the slot machines but don't really understand their true origins or how they came about. Yes, one might know that a man named Charles Fey invented the first slot machine in 1895, but what was the theory behind his great invention?

Charles Fey was a successful mechanic who liked to play around with machinery in his spare time. He had a small workshop where he lived and spent many an evening fiddling and playing with all sorts of mechanical ideas. He was also a keen card player but due to his low income he could not afford to spend many evenings in the casinos. He came up with the idea of spinning reels one night just when he was getting frustrated with not being able to go to the casino again.

As the idea grew in his head, he started working on it and came up with a mechanical machine with three separated tubs or reels that would spin independently of each other when a lever was pulled. With the help of notches and ridges on the reels, they would all spin at different speeds and come to rest at different places. To this he added the picture cards of the Kings, Queens, and Jacks, and thus the first slot machine was invented. When a line of the same cards — such as all kings or all queens — was drawn, a bell rang and a winner was declared. Charles Fey gave the name Liberty Bell to this machine and made his fortune from it. This original Liberty Bell machine was a fancy machine that stood on claw feet and the public loved it.

The Liberty Bell was just the first of many slot machines. Initially they were considered mere diversions for the wives and partners of the high-rolling gamblers who were happy to let their partners keep busy with what they thought were the small-change machines. But within twenty years the mechanical slot machines had become the most popular game in casinos and leisure houses. In some places they were known as the "one-armed bandits" in honor of the lever that was pulled.

As the popularity of the slot machines grew, so did the technology: the original three-reel machines changed into five reels, the machines became more detailed with microprocessors controlling the spinning, and the winning lines were controlled by Random Number Generators. Levers were no longer needed to activate the machines and buttons were pressed instead. These were all major advances in slot machine history.

The next big step in the history of the slot machine was the creation of the online casino in the late 20th century. With the online casino, of course, came online slots. As in the traditional casinos, the slot machines proved to be the most popular game in the online casinos. People found that they could win at slots — sometimes winning many thousands of dollars — without having to travel to a casino. Even when they did not win, they enjoyed the convenience and the excitement of playing slot machines online from the comfort of home.

Now in the 21st century, more than 100 years after Charles Fey had originally played around in his garage, slot machines are the biggest attractions in both land-based and online casinos. The wide and varied different themes, and the low investment that is needed to play the slots, have kept slot machines as the most popular casino game for all of these years.