The first nationally known poker-card machines were developed in 1891 by a couple of guys named Sittman and Pitt from Brooklyn, N.Y. Prior to this date, and following the gold rush of 1848, coin-operated gaming devices, which had been developed in the east in the late 1880s, gained popularity in saloons and cigar stores in San Francisco. Poker gaming devices, specifically, appeared in San Francisco as early as 1890.
These early inventions, which took either a penny or a nickel, from what we can tell, were called "drop card machines" and used 50 cards spread across five drums, i.e., two cards short of a full deck. The jack of hearts and ten of spades were usually the cards left out, which cut the possibility of getting a royal flush in half. What we'd recognize today as the first slot machines became legal devices in 1897 and opened the door to a move away from five-reel poker machines, that yielded cigars and drinks as winnings, to cash-paying poker machines.
The most important development came in 1901 when pioneering slot inventor Charles Fey added the "draw" feature. All five drums would spin on the first pull. When they stopped, the player had a choice to create a better hand by pushing buttons to hold selected cards. With the second pull, the final hand would appear.
In 1964, Nevada Electronics built what were called solid-state "21" machines. Then during the '70s, other companies built roulette, 21, and dice machines. Around 1970 or '71 (there’s some debate about the year), Dale Electronics’ notable "Poker-Matic" machine debuted, and could soon be found in most Nevada casinos. In 1975, the Fortune Coin Co. introduced the first "Bell Slot Machine" (the precursor to the modern slot) to Las Vegas, but interestingly, the device received only lukewarm acceptance and it was not until it was made into a poker machine that its potential became obvious. The invention of the video chip in the mid-'70s enabled Bally to build a black-and-white video poker machine in 1976 and, eight months later, the Fortune Coin Co. fired back with a color version.
In 1979, International Game Technology (IGT) introduced its "Draw Poker" machine, which became wildly popular and is credited with creating the frenzy surrounding video poker during the 1980s and '90s, when it even became labeled as the "crack cocaine of gambling."