Originally, Sittman and Pitt of Brooklyn, New York developed a gambling machine in 1891, which was the precursor to the modern slot machine. It contained five drums with a total of 50 cards and was based on poker. The machine proved to be very popular and soon many bars in town had one or more. Players would insert a nickel and pull a lever which would rotate the drums and the cards they held as the player hoped for a good hand.

    Since there was no direct payout mechanism, a “pair of kings” from the machine might get a player a free beer, while a “royal flush” could get a free cigar or a drink; the prizes depended entirely on what the bar offered. To improve the dealer's chances, two cards are usually removed from the pile, the 10 of spades and the jack of hearts, thus doubling the chances of winning a royal flush. The drums could also be rearranged to further reduce the player's chances of winning.

    Next, the first Liberty Bell machine produced by Mills used the same symbols on the reels as the original Charles Fey version. Soon after, another version featured patriotic symbols on the reels, such as flags and wreaths. Later, a similar machine called Operator's Bell was produced that included the option to add a gumball vending machine attachment. Since the gum offered was fruit-flavored, fruit symbols were placed on the reels: lemon, cherry, orange, and plum, a bell was retained, and a picture of a bell pectin stick was displayed, which was the origin of the bar symbol. This set of symbols proved to be very popular and was used by other companies that started to manufacture their own slot machines: Caille, Watling, Jennings and Pace.

    However, the first video slot machine was developed by Las Vegas-based Fortune Coin in 1976 in Kearny Mesa, California. This machine used a modified 19-inch Sony Trinitron color receiver as the display and logic board-machine feature for all slot machines. The prototype was installed in a full-size, display-ready slot cabinet.

    The first production units were trialed at the Las Vegas Hilton. After some modifications to defeat cheating attempts, video slot machines were approved by the Nevada Gaming Commission and eventually became popular in casinos on the Las Vegas Strip and downtown.Fortune Coin Co. and its video slot machine technology were purchased by IGT (International Gaming Technology), 1978.