Commodore Grace M. Hopper, USN
First to "Debug"
Rear Admiral Grace Hopper (December 9, 1906 – January 1, 1992) was an American computer scientist and United States Navy rear admiral commissioned officer. A pioneer in the field, she was one of the first programmers of the Harvard Mark I computer, and developed the first compiler for a computer programming language. She also coined the term “debugging”.
The First "Computer Bug" Moth found trapped between points at Relay # 70, Panel F, of the Mark II Aiken Relay Calculator while it was being tested at Harvard University, 9 September 1947. The operators affixed the moth to the computer log, with the entry: "First actual case of bug being found". (The term "debugging" already existed; thus, finding an actual bug was an amusing occurrence.)