Before smartphones, tablets, and trackpads we had keyboards and mice. Our devices were connected to us through peripherals that interpreted our input graphically. Scrolling and selecting was done with the click of your mouse or a keystroke. And now we've evolved to swiping and tapping to interact with devices. 
That got me thinking about how we use gestures in the digital world. And how the user experience with these gestures helps make them intuitive and fun to use.