Computers were programmed to swap out error-prone, inconsistent human calculation with digital perfection.

Computers were programmed to swap out error-prone, inconsistent human calculation with digital perfection.

In 1986, the space shuttle Challenger exploded and crashed down to Earth less than two minutes after takeoff. The cause of that crash, it turned out, was an inexpensive rubber O-ring in the booster rocket that had frozen on the launchpad the night before and failed catastrophically moments after takeoff.