Discovery of 'First Actual Bug'

Name: Discovery of 'First Actual Bug'
Start: 1947-09-09
Location: Harvard University, Cambridge, Massachusetts, USA

During work on the Mark II Aiken Relay Calculator, a moth was found jammed in a relay, causing an error. Grace Hopper taped it into the logbook, coining the term 'debugging' for error fixing.

Significance

While not 'testing' in the systematic sense, this iconic event cemented the term 'debugging' into the computing lexicon and highlighted the tangible nature of computer errors, leading to a more focused effort on identifying and resolving them.

Key facts

Date: 1947-09-09
Type: milestone
Location: Harvard University, Cambridge, Massachusetts, USA