'If any task on the Palm Pilot takes more than three taps of the stylus, it's too long, and it has to be redesigned.'

Um, so, it was negatively skewed. I can show that, show those distributions instead of me awkwardly drawing with the stylus, I, I promise to get better.

It's certainly a very important medium for input, and a lot of people think that fingers are a very low resolution sort of stylus for inputting to a display.

In Angola, the Chokwe people draw lines in the sand, and it's what the German mathematician Euler called a graph we now call it an Eulerian path you can never lift your stylus from the surface and you can never go over the same line twice.

And we make a mathematical model of those relationships and program them into a tablet computer so that when you take the stylus and go and touch the screen, that voice coil actuator in the white bracket plays vibrations to give you the illusion that you're touching the real surface, just like if you touched, dragged back and forth, on the real canvas.