There’s something instantly readable about a bubble drifting upwards, wobbling slightly, then popping with a neat flash of colour. You don’t need a tutorial to understand it. A bubble looks light, round and fragile, so players naturally expect it to move in a certain way. That expectation is why bubble physics has lasted so well […] Post Why Bubble Motion Still Works in Digital Interfaces at Root-Nation.com.

We programmed them by punching cards, plugging in wires, and flipping switches. Programmers walked among banks of switches and cables, physically choreographing their logic. Being on a computer used to be a full-body experience.