For more than a century, slot machines have required little more than cash and the faith that you will hit the jackpot. But a new generation of machines, designed to lure younger gamblers who grew up with video games, is demanding something else: skill.

Whether they’re in the casino or on a mobile device, slot developers are leaning heavily on data to determine what makes a game stick. As companies like ReelMetrics offer more sophisticated analysis, operators and manufacturers are on a quest to identify features that make players keep playing.

One such trend is the proliferation of “skill stop” buttons, which allow players to control the number of spins. The buttons, which are similar to those on a video game controller, appear on the touchscreen interface of a new wave of slot games. Players use them to set the number of reels they want to spin and the paylines they want to activate, as well as adjust their bet amount.

Another development is the emergence of virtual reality slots. The technology allows players to enter a virtual world and interact with different characters. These virtual slots have an immersive quality and can be played on smartphones, tablets, and computers.

Throughout the evolution of slot machines, each new innovation inspired commensurate cheating techniques. Starting with plugged-in nickels and laundry detergent poured into the slots, to Jenny’s Shaker and shims that manipulate Mills and Buckley machines, and finally the top-bottom joint, which infamously inspired Chevy Chase’s Clark W. Griswold in National Lampoon’s Vegas Vacation, slot cheaters have been at work for decades.