Grace Hopper

Grace Hopper was a pioneering computer scientist who joined the US Navy's reserves as part of the Mark 1 programming staff. She can be credited with many things: development of the UNIVAC 1, the creation of the first compiler and use of English in programming languages. After multiple attempts to retire from the Navy and multiple returns to continue her work, she left with a Rear Admiral.

She was an excellent speaker, comedian and entertainer, evidenced by her many one-liners:

They told me computers could only do arithmetic.

Life was simple before World War II. After that, we had systems.

One accurate measurement is worth a thousand expert opinions.

I've always objected to doing anything over again if I had already done it once.


In the course of her career, Hopper popularised (or is credited with popularising) many terms commonplace in computing today:

  • Patching has its roots in punching punch cards and paper tape.
  • Debugging in the removal of bugs from relays in the Mark 1.


Both her mother and father had an intense interest in mathematics, and her father worked in insurance and had access to adding machines for performing calculations. Her intense curiosity for how things worked -- which she famously shared through a story about disassembling seven clocks -- likely got its start through this and the encouragement of her father to not follow the traditional path/role of a woman.

Hopper was born in New York City and was one of the first to get electricity to her family home. She graduated from Vassar with a degree in Physics and Mathematics, then later studied for her PhD in Mathematics at Yale.

Hopper was described as "very traditional", not identifying as a feminist or with women's liberation. She showed her support for the military by wearing full naval attire to her class at Vassar, even during the Vietnam war when the military was deeply unpopular.


Hopper was concerned with data flow and processing, and acknowledged early the relatively high value of data compared to the value of the systems that processed it. She drew inspiration from the impact of the car on the overall transport network, using the lack of available rail infrastructure as an example of the need for holistic review of "interconnected systems" rather than focusing on individual machines (computers, and the car).


  • 1906: birth.
  • 1924: entered Vassar, studying mathematics and physics.
  • 1928: graduated Vassar.
  • 1931: joined Vassar faculty, teaching mathematics.
  • 1934: completed PhD at Yale.
  • 1941: separated from husband.
  • 1942: rejected from WAVES for "not weighing enough".
  • 1943: accepted into WAVES.
  • 1944: commissioned as Lieutenant (junior grade), beginning work on Mark II programme.
  • 1945: divorced husband.
  • 1951-1952: wrote A-0 System, the first loader/linker, a precursor to the first compiler, followed by A-1, A-2 and A-3. The A-2 System source code was provided to customers in an early example of open source software.
  • 1955-1959: wrote B-0, known as FLOW-MATIC.
  • 1959: worked on the committee that wrote and published the COBOL specification.
  • 1966: retired from the Navy, aged 60.
  • 1967: called back to standardise COBOL for the Navy.
  • 1969: first "Computer Science Man of the Year".
  • 1986: final retirement.
  • 1992: death.