Grace Hopper
Grace Brewster Hopper was an American computer scientist, mathematician, and United States Navy rear admiral. She was a pioneer of computer programming. Hopper was the first to devise the theory of machine-independent programming languages, and used this theory to develop the FLOW-MATIC programming language and COBOL, an early high-level programming language still in use today. She was also one of the first programmers on the Harvard Mark I computer. She is credited with writing the first computer manual, "A Manual of Operation for the Automatic Sequence Controlled Calculator."
Before joining the Navy, Hopper earned a Ph.D. in both mathematics and mathematical physics from Yale University and was a professor of mathematics at Vassar College. She left her position at Vassar to join the United States Navy Reserve during World War II. Hopper began her computing career in 1944 as a member of the Harvard Mark I team, led by Howard H. Aiken. In 1949, she joined the Eckert–Mauchly Computer Corporation and was part of the team that developed the UNIVAC I computer. At Eckert–Mauchly she managed the development of one of the first COBOL compilers.
She believed that programming should be simplified with an English-based computer programming language. Her compiler converted English terms into machine code understood by computers. By 1952, Hopper had finished her program linker, which was written for the A-0 System. In 1954, Eckert–Mauchly chose Hopper to lead their department for automatic programming, and she led the release of some of the first compiled languages like FLOW-MATIC. In 1959, she participated in the CODASYL consortium, helping to create a machine-independent programming language called COBOL, which was based on English words. Hopper promoted the use of the language throughout the 60s.
The U.S. Navy guided-missile destroyer was named for her, as was the Cray XE6 "Hopper" supercomputer at NERSC, and the Nvidia GPU architecture "Hopper". During her lifetime, Hopper was awarded 40 honorary degrees from universities across the world. A college at Yale University was renamed in her honor. In 1991, she received the National Medal of Technology. On November 22, 2016, she was posthumously awarded the Presidential Medal of Freedom by President Barack Obama. In 2024, the Institute of Electrical and Electronics Engineers dedicated a marker in honor of Grace Hopper at the University of Pennsylvania for her role in inventing the A-0 compiler during her time as a Lecturer in the School of Engineering, citing her inspirational impact on young engineers.
Early life and education
Grace Brewster Murray was born in New York City. She was the eldest of three children. Her parents, Walter Fletcher Murray and Mary Campbell Van Horne, were of Scottish and Dutch descent, and attended West End Collegiate Church. Her great-grandfather, Alexander Wilson Russell, an admiral in the US Navy, fought in the Battle of Mobile Bay during the Civil War.Grace was very curious as a child; this was a lifelong trait. At the age of seven, she decided to determine how an alarm clock worked and dismantled seven alarm clocks before her mother realized what she was doing. Later in life, she was known for keeping a clock that ran backward; she explained, "Humans are allergic to change. They love to say, 'We've always done it this way.' I try to fight that. That's why I have a clock on my wall that runs counterclockwise." For her preparatory school education, she attended the Hartridge School in Plainfield, New Jersey. Grace was initially rejected for early admission to Vassar College at age 16, but she was admitted the next year. She graduated Phi Beta Kappa from Vassar in 1928 with a bachelor's degree in mathematics and physics and earned her master's degree at Yale University in 1930.
In 1930, Grace Murray married New York University professor Vincent Foster Hopper ; they divorced in 1945. She did not marry again and retained his surname.
In 1934, Hopper earned a Ph.D. in mathematics from Yale under the direction of Øystein Ore. Her dissertation, "New Types of Irreducibility Criteria", was published that year. She began teaching mathematics at Vassar in 1931, and was promoted to associate professor in 1941.
Career
World War II
Hopper tried to be commissioned in the Navy early in World War II, however she was turned down. At age 34, she was too old to enlist and her weight-to-height ratio was too low. She was also denied on the basis that her job as a mathematician and mathematics professor at Vassar College was valuable to the war effort. During the war in 1943, Hopper obtained a leave of absence from Vassar and was sworn into the United States Navy Reserve; she was one of many women who volunteered to serve in the WAVES.She had to get an exemption to be commissioned; she was below the Navy minimum weight of. She reported in December and trained at the Naval Reserve Midshipmen's School at Smith College in Northampton, Massachusetts. Hopper graduated first in her class in 1944, and was assigned to the Bureau of Ships Computation Project at Harvard University as a lieutenant, junior grade. She served on the Mark I computer programming staff headed by Howard H. Aiken.
Hopper and Aiken co-authored three papers on the Mark I, also known as the Automatic Sequence Controlled Calculator. Hopper's request to transfer to the regular Navy, out of WAVES, at the end of the war was denied due to being two years older than the cutoff age of 38. She continued to serve in the Navy Reserve. Hopper remained at the Harvard Computation Lab until 1949, turning down a full professorship at Vassar in favor of working as a research fellow under a Navy contract at Harvard.
File: Grace Murray Hopper, in her office in Washington DC, 1978, ©Lynn Gilbert.jpg|thumb|upright|left|Hopper in a computer room in Washington, D.C., 1978, photographed by Lynn Gilbert
UNIVAC
In 1949, Hopper became an employee of the Eckert–Mauchly Computer Corporation as a senior mathematician and joined the team developing the UNIVAC I. Hopper also served as UNIVAC director of Automatic Programming Development for Remington Rand. The UNIVAC was the first known large-scale electronic computer to be on the market in 1951.When Hopper recommended the development of a new programming language that would use entirely English words, she "was told very quickly that couldn't do this because computers didn't understand English." Still, she persisted. "It's much easier for most people to write an English statement than it is to use symbols", she explained. "So I decided data processors ought to be able to write their programs in English, and the computers would translate them into machine code."
Her idea was not accepted for three years. In the meantime, she published her first paper on the subject, compilers, in 1952. In the early 1950s, the company was taken over by the Remington Rand corporation, and it was while she was working for them that her original compiler work was done. The program was known as the A compiler and its first version was A-0.
In 1952, she had an operational link-loader, which at the time was referred to as a compiler. She later said that "Nobody believed that", and that she "had a running compiler and nobody would touch it. They told me computers could only do arithmetic."
In 1954 Hopper was named the company's first director of automatic programming. Beginning in 1954, Hopper's work was influenced by the Laning and Zierler system, which was the first compiler to accept algebraic notation as input. Her department released some of the first compiler-based programming languages, including MATH-MATIC and FLOW-MATIC.
Hopper said that her compiler A-0, "translated mathematical notation into machine code. Manipulating symbols was fine for mathematicians but it was no good for data processors who were not symbol manipulators. Very few people are really symbol manipulators. If they are, they become professional mathematicians, not data processors. It's much easier for most people to write an English statement than it is to use symbols. So I decided data processors ought to be able to write their programs in English, and the computers would translate them into machine code. That was the beginning of COBOL, a computer language for data processors. I could say 'Subtract income tax from pay' instead of trying to write that in octal code or using all kinds of symbols. COBOL is the major language used today in data processing."
COBOL
In the spring of 1959, computer experts from industry and government were brought together in a two-day conference known as the Conference on Data Systems Languages. Hopper served as a technical consultant to the committee, and many of her former employees served on the short-term committee that defined the new language COBOL. The new language extended Hopper's FLOW-MATIC language with some ideas from the IBM equivalent, COMTRAN. Hopper's belief that programs should be written in a language that was close to English was captured in the new business language, and COBOL went on to be the most ubiquitous business language to date. Among the members of the committee that worked on COBOL was Mount Holyoke College alumna Jean E. Sammet.From 1967 to 1977, Hopper served as the director of the Navy Programming Languages Group in the Navy's Office of Information Systems Planning and was promoted to the rank of captain in 1973. She developed validation software for COBOL and its compiler as part of a COBOL standardization program for the entire Navy.