On September 9, 1947, the Harvard University Mark II Aiken Relay Calculator started having problems. The operators opened it up, and discovered a moth between the points of Relay #70, in Panel F. The moth was removed at taped into the log book with the comment “First actual case of bug being found.”

When told of the event, Grace Murray Hopper was reported to have quipped they were “debugging” the machine. There is plenty of evidence the term “bug” for a flaw in electronics had been around for decades before this event, this usage helped bring it into the modern popular terminology.

This is also the first introduction that many of us have to Rear Admiral Hopper, a truly remarkable woman. She wrote the first compiler for an electronic computer, A-0. She championed the idea that computer languages should be more like English instead of machine code. And she helped establish standards for testing systems and components.

The next time I have to debug a program written in a 3GL, I’ll take a moment to thank Grace Hopper for laying the groundwork that made it easier for me. Thank you, Amazing Grace!