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Women’s History Month: Grace Hopper, Inventor of the First Compiler

Who Was Grace Hopper?

Grace Hopper was an American mathematician and rear admiral in the US Navy. She was a pioneer in computer technology for many reasons. One of the major reasons is that she was the inventor of the first compiler and helped to create the UNIVAC 1, the world’s first commercial electronic computer. She also promoted the use of COBOL (common business-oriented language) as the first standardised business computer language in the military and private sector. The popularisation of the term ‘bug’ and ‘debug’ was due to her too. As you will read below, she has been influential in so many things that we use today in tech. 

Early Life

Grace Hopper was born Grace Brewster Murrary on the 9th of December 1906 in New York. She was known to have shown an interest in engineering at a young age, taking apart household goods and learning how to put them back together.

Hopper went to Vassar College in New York and achieved her BA in Mathematics and Physics in 1928. After that, in 1930, she went to Yale University to get her Phd in mathematics. Also in 1930, she married Vincent Foster Hopper. They divorced in 1945, but she kept the last name ‘Hopper’. She was a maths professor at Vassar University up until she joined the Navy in 1943. 

US Navy & Harvard

Hopper joined the Navy WAVES (Women Accepted for Voluntary Service) and by the time she made the lieutenant rank she worked in the Bureau of Ordnance’s Computation Project at Harvard University. Here, she worked on the first large scale automatic calculator, the ‘Mark I’, which was the forerunner for electronic computers. In 1946, Hopper wrote the 500 page ‘Manual of Operation for the Automatic Sequence Controlled Calculator’, which was the first computer manual and discussed how to operate the Mark I. She became a reservist in the Navy and stayed at Harvard as a civilian research fellow. As I mentioned earlier, Hopper popularised the term ’debugging’, as the term ‘bug’ actually came about when a moth flew into the Mark I circuits and created a few issues. 

Hopper worked on the MARK II and Mark III computers under Navy contracts. However at the end of her 3 year research fellowship she had to leave Harvard as there weren’t any permanent positions for women. 

The First Compiler

1949 brought about some change for Hopper as she joined the Eckert-Mauchly Computer Corporation. This is where, in 1952, she designed one of the first compilers, called A-0, to translate a programmer’s instructions into computer codes, thus conceiving the word ‘compiler’. This was an important step towards creating modern programming languages. 

She became head programmer and worked on the design of the UNIVAC, even when the firm was taken over twice, by Remington Rand in 1951, and by Sperry Rand Corporation in 1955. By 1957 her team had created ‘Flow-Matic’, which was the first English language data-processing compiler. The Flow-Matic had a lot of qualities that led to the development of COBOL. 

She was a strong advocate for COBOL and contributed to its widespread use in the 1960s. She had retired from the Navy in 1966 but was actually called back in 1967 to help implement COBOL and standardise the Navy’s computer languages. Her work led her to be promoted to commodore by 1983, and rear admiral in 1985. She finally retired in 1986, aged 79, as the oldest officer on active US Naval duty. 

Post Naval Retirement

In the same year that Hopper retired from the Navy she went to work as a senior consultant in PR at the Digital Equipment Corporation. She worked here until she passed in 1992, when she was buried with full military honours in Arlington Cemetery. Even after gaining all her accomplishments, Hopper is quoted to have said, “if you ask me what accomplishment I’m most proud of, the answer would be all the young people I’ve trained over the years; that’s more important than writing the first compiler.” She had a real joy for teaching and went back into the classroom to teach after her retirement until she passed. 


Grace Hopper was nicknamed ‘Amazing Grace’ by many of her peers due to her variety of accomplishments both in the Navy and in maths and science. She excelled in a male-dominated field and a male dominated organisation. Here’s a snippet of how she has been recognised for these accomplishments;

1962 – Hopper was made a fellow of the Institute of Electrical and Electronic Engineers.

1969 – she became the first computer scientist named Man of the Year by the Data Processing Management Association. 

1972 – she was awarded Yale’s Wilbur Lucius Cross Medal which was given to outstanding alumni.

1973 – she was the first woman and first American to become a Distinguished Fellow of the British Computer Society.

1991 – she was the first individual woman to be awarded the National Medal of Technology by President George Bush for “her pioneering accomplishments in the development of computer programming languages that simplified computer technology and opened the door to a significantly larger universe of users.”

1996 – the US Navy commissioned a guided military destroyer named the ‘USS Hopper’. 

2004 – the University of Missouri created a computer museum on campus known as “Grace’s Place”. Early computers and components are on display to educate visitors on the evolution of that tech. 

2016 – she was posthumously awarded the Presidential Medal of Freedom by President Obama.

2010 – the Cray XE6 “Hopper” supercomputer at the NERSC (National Energy Research Scientific Computing Centre) was named after her. 


“Five fast facts about technologist Grace Hopper”, Lantero, A. March 2015

“Rear Adm. Grace M. Hopper dies; innovator in computers was 85”. New York Times. January 1992

“President Obama names recipients of the presidential medal of freedom”. White House Press Release. November 2016 

“Grace Hopper”. Norwood, A, Women’s 2017

“Grace Hopper Biography”. Accessed March 2022

  • Written by Mikita Maru, March 28 2022