Tedium:

So, as it turns out, before the virtual bowling alley borrowed something from the trackball, the inventors of the trackball borrowed something from the actual bowling alley—specifically, the Canadian variation of it, called 5-pin bowling.

And:

The [trackball] is Canadian through and through, a project formulated at the behest of the Royal Canadian Navy by Ferranti Canada, as part of a much larger project—a military information system called Digital Automated Tracking and Resolving, or DATAR.

And:

“Think about the state of play in the computer world in 1952. There were only a handful of operating computers in the world. Almost all were unreliable. There was no common software language… pulse rates were only 50-100kHz. The idea of using a ball to control a cursor which could intervene and change program execution was a million miles ahead.”

This is a terrific look back at a device that changed the path of computing. [Via The Overspill]