I heard Grace Hopper use this term in the late 70s in a talk at a computer conference

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She was a special guest at a week-long certification training - EDP Auditors. She told the Moth story, but did not attribute the term to anyone other than herself. I would say from what I read here, she did not originate it, but she may have had a great deal to do with its popularization. She was an incredibly impressive individual. An admiral, in her Navy uniform, slim, somewhat frail, looking to be in her 80s (actually only in her early 70s at the time). She was right there at the dawn of the computer era. The irony is that the conference was held in San Francisco in the late 70s, at the VERY TIME that the PC industry was being created in Silicon Valley.