Salem Press

Great Lives from History: The 20th Century
Grace Murray Hopper

American computer scientist

A pioneer in programming languages, Hopper developed FLOW-MATIC, the foundation of the computer language known as COBOL, and then standardized all U.S. Navy versions. Her work helped lay the foundations of the information age.

Born: December 9, 1906; New York, New York
Died: January 1, 1992; Arlington, Virginia
Also Known As: Grace Brewster Murray (birth name); Grand Old Lady
of Software; Amazing Grace
Areas of Achievement: Computer science, mathematics, invention
and technology

Early Life
Grace Murray Hopper was the eldest of three children born to Walter Murray, an insurance broker, and his wife Mary Campbell Van Horne Murray. In reflecting on her childhood, Hopper later said, "I was born with curiosity." When she was seven years old, she wandered into the bedrooms of the family's large summer cottage and, out of curiosity, deconstructed seven alarm clocks. Her hobbies included reading and playing the piano. She eventually became expert at knitting, a pastime she would continue all her life.

Hopper attended the Graham School and later Schoonmakers School, two private schools in New York City where she played basketball, field hockey, and water polo. When she flunked a crucial Latin exam, Vassar College told her she would have to wait a year to enter. For remediation, Hopper became a boarding student at Hartridge School in Plainfield, New Jersey, and continued her record of active participation. The quotation selected to describe her in the yearbook proclaimed, "In action faithful and in honor clear."

During all of her schooling, Hopper loved mathematics, especially geometry. She remembered, "I used to draw pretty pictures with it." When she entered Vassar College in 1924, her interests in mathematics combined with those in physics and engineering. A gifted student, Hopper also audited all the beginning courses in botany, physiology, and geology. She continued to play basketball and sought out adventure, once flying in a barnstorming biplane over the campus.
A Phi Beta Kappa graduate from Vassar in 1928 with a bachelor of arts degree in mathematics and physics, Hopper undertook graduate studies at Yale University, where she was invited to join Sigma Xi, an honor society that recognizes scientists for their outstanding research achievements. After receiving her master's degree from Yale in 1930, Hopper was married to Vincent Foster Hopper on June 15, 1930.

Because jobs were scarce during the Great Depression, Hopper seized the opportunity to teach at Vassar in 1931 at a salary of eight hundred dollars per year. As an assistant professor in mathematics, she taught algebra, trigonometry, and calculus. The Hoppers built a house in Poughkeepsie, New York, near the Vassar campus, and Vincent, a teacher, commuted to New York City until they were divorced in 1945. Hopper earned her Ph.D. in mathematics and mathematical physics from Yale in 1934, a significant accomplishment for that era. Her doctoral thesis was entitled "A New Criterion for Reduceability of Algebraic Equations."

Highly patriotic, Hopper yearned to serve her country during World War II. After threatening to quit her post at Vassar, she obtained a leave of absence in order to enter the United States Naval Reserve (USNR). Her admission to the reserve was nearly denied because she weighed only 105 pounds, not the requisite 121 pounds. After obtaining a waiver, in 1943, Hopper entered the USNR Midshipman's School for Women in Northampton, Massachusetts. Despite early errors in identifying carriers and submarines, Hopper graduated first in her class and was commissioned lieutenant, junior grade, on June 27, 1944. She was immediately assigned to the Bureau of Ships Computation Project in Cruft Laboratory at Harvard University with Howard Aiken as director. This assignment, unique because there were fewer than six computer projects under way in the United States, would change the course of her career.

Life's Work
When Hopper reported to work on July 2, 1944, Commander Aiken waved his hand at the Mark I installation and introduced her to this "computing engine," the first programmable digital computer in the United States. He gave her a code book and asked to have the coefficients for the interpolation of the arc tangent ready by the following Thursday.
Mark I, also known as the Automatic Sequence Controlled Calculator, could do three additions every second—important because rapid computations were needed for the new weapons systems. Mark I was a monster of a machine: 51 feet long, 8 feet deep, 8 feet high, and approximately 5 tons in weight. It had 800,000 parts and contained more than 500 miles of wire. Mark I was fed instructions and data punched out on four long paper tapes: one control tape for instructions and three tapes for data input.

To program the Mark I, instructions had to be written in a machine code that told the computer exactly what operations to perform and their precise sequence. The instructions detailed which switches were to be set at either the on or off position, and a new program representing a different pattern of codes had to be written for each task or problem. Because it was easy to make errors, Hopper and her colleagues collected correct programs in a notebook with a routine for the sine, cosine, and the arc tangent. As one of her first challenging tasks, Hopper wrote an operating manual for the computer that eventually became one of the most famous documents in the literature of computers. In this manner, Hopper became the third programmer on the first large-scale digital computer in the United States.

The U.S. Navy leased the Mark I for the remainder of the war to compute quickly the complex calculations necessary to aim new Navy guns with precision. Hopper and her staff of three other officers and four enlisted men operated around the clock, providing critical information about ballistic trajectories. She later said, "I slept nights on a desk to see if my program was going to get running."

Hopper stayed on at Harvard after the war and joined the faculty as a research fellow in 1946. The Mark II, a multiprocessor, had been designed, built, and tested for the Navy Bureau of Ordnance since Hopper's arrival at Harvard and was five times faster than the Mark I. In the summer of 1947, a moth was found in the computer, beaten by a relay which then stopped functioning well, causing erroneous information. The two-inch moth was taped into a notebook and described as "first actual bug found." Later, when little work was being accomplished, Hopper and others would use the handy excuse that they were "debugging" the machine.
In 1949, she joined the Eckert-Mauchly Corporation, a Philadelphia firm run by John W. Mauchly and J. Presper Eckert, coinventors and developers of the world's first electronic computer, known as ENIAC (Electronic Numerical Integrator and Calculator). The company had also built EDVAC and BINAC, binary automatic computers, and was building UNIVAC I (Universal Automatic Computer), the first commercial electronic computer. This new, smaller computer had many memory devices, including storage tubes and a magnetic core, and was one thousand times faster than the Mark I. Hopper joined the company as senior mathematician.
Hopper reasoned that if computers could be used to write their own programs, they would be used for business purposes. Accordingly, she developed a compiler to alleviate the problem of mistakes in code writing that developed when programs had to be written in octal code (base 8 instead of 10). The compiler translated the programmer's mathematical notations into the machine's binary language and performed the calculations. Her first compiler in 1952 was the A-0 System, standing for algebraic codes starting with routines at zero. By 1955, she had developed A-2, the first compiler to use mathematical computations extensively.

Next, Hopper developed the B-0 compiler for business, the first computer language employing English words rather than mathematical symbols. Earlier called MATH-MATIC, B-0 or FLOW-MATIC was an enormous advance in the development of programming languages. To create FLOW-MATIC, Hopper wrote five hundred typical programs and identified thirty verbs common to all programs including words such as count, divide, subtract, move, replace, and multiply. She later claimed that she wrote this language because she was lazy: While other programmers wanted to play with the bits, she wanted to get the job done.

By 1959, there were three major computer languages, each requiring one specific computer. That year, a committee was authorized to develop a common business-oriented language to be used with any kind of computer. Heavily influenced by Hopper's FLOW-MATIC, the resulting product, COBOL, uses syntax and terms close to natural English, is easy to understand, and is efficient at processing large quantities of information. Because the Defense Department urged businesses to adopt COBOL if they wanted to continue selling their products to the government, COBOL eventually became the most widely used business computer language.

Hopper retired from the Naval Reserve when she reached the age of sixty in 1966 with the rank of commander. Much to her delight, however, the Navy discovered that it could not get along without her. Its payroll program had to be rewritten 823 times. Seven months later, on August 1, 1967, she was called out of retirement to standardize the high-level languages and get the entire Navy to use them. Specifically, Hopper was asked to develop a COBOL certifier, a set of programs that would tell the user whether a compiler labeled COBOL was legitimate for use.
Hopper was initially recalled for six months, but the orders were changed to "indefinite"—allowing her to work for nearly twenty additional years. During the years she served as director of the Navy Programming Languages Group, Hopper developed a manual called Fundamentals of COBOL to train people on its use as well as a catalog with user hints and an index of sample statements.

In a ceremony held in August of 1986, on "Old Ironsides," the oldest commissioned warship, Hopper retired from the Navy at the age of seventy-nine with the rank of rear admiral. As the oldest commissioned naval officer on active duty, she said, "I love this ship. We belong together." At that time the only woman admiral in the history of the Navy, Hopper telephoned her friends in Philadelphia to watch the grave of her great-grandfather Russell, who had also been a rear admiral, humorously warning them that he might rise from the dead. Never one to rest, Hopper immediately began working as a senior consultant for Digital Equipment Corporation.

Hopper received many prestigious honors, among them the Man of the Year award from the Data Processing Management Association (1969) and induction into the Engineering and Science Hall of Fame in Dayton, Ohio (1984). In recognition of her extraordinary contributions, the Navy dedicated the Grace Murray Hopper Service Center of the Navy Regional Data Automation Center in San Diego, California, in 1985. In 1991, President George H. W. Bush awarded Hopper the National Medal of Technology, and she became the first woman to receive it individually.

Hopper was witty, unorthodox, and sometimes combative—a self-described "boat rocker." She died at age eighty-five of natural causes.

Significance
Known as the Grand Old Lady of Software, Hopper is considered a primary leader in developing compilers and standardizing computer languages. Cynics scoffed at the idea that computer programs could be written in English, but Hopper confidently proved otherwise.
An innovator, she accomplished many things: She helped to lift computing out of the mechanical age and into the era of electronics, she also helped to modernize the Navy by standardizing its use of the computer, and she played a major role in building COBOL, thus making computers accessible to nonmathematicians.

Later in her life, not satisfied to rest on her laurels, Hopper became an ardent spokesperson for education and a public relations asset for the Navy. Amazing Grace, as her associates called her, traveled all over the country, encouraging risk-taking and innovation. She spoke as many as two hundred times a year, especially to young audiences. A lover of possibilities, she shared her philosophy with them: "Go ahead and do it. You can always apologize later."

As an educator, she worried that computers might create a new kind of gender discrimination: Men would be thinkists, women typists. Hopper insisted that females must study computer science, engineering, and business and gain confidence in their abilities as individuals. She believed women are as capable as men of doing programming and that computing is a good field for career mobility. "Women turn out to be very good programmers for one very good reason: They tend to finish up things, and men don't very often," she stated. Despite her obvious support of women, Hopper once called the women's movement "tommyrot and nonsense." She firmly believed that skilled, ambitious women would not be held back.

Deborah Elwell Arfken

Further Reading
Billings, Charlene W. Grace Hopper: Navy Admiral and Computer Pioneer. Hillside, N.J.: Enslow, 1989. A biography for adolescents with a thorough assessment of Hopper's life. Clear explanations of Hopper's groundbreaking work with compilers. Excellent photographs.

Gilbert, Lynn, and Gaylen Moore. "Grace Murray Hopper." In Particular Passions: Talks with Women Who Have Shaped Our Times. New York: Clarkson N. Potter, 1981. Lively interviews with thirty-nine celebrated women. Hopper was seventy-three years old at the time of her firsthand account.

Hopper, Grace Murray, and Steven L. Mandell. "Man the Thinkist, Woman the Typist?" In Understanding Computers. 2d ed. St. Paul, Minn.: West, 1987. A provocative essay in Hopper's now-classic textbook.

Slater, Robert. "Grace Murray Hopper: Bugs, Compilers, and COBOL." In Portraits in Silicon. Cambridge, Mass.: MIT Press, 1987. A portrait focusing on Hopper as a software specialist.

Smith, William D. "Pioneer in Computers: Navy Officer Likes to Rock Boat." The New York Times, September 5, 1971, Sec. III, p. 5. A frank interview with Hopper regarding her scientific career.

Tropp, Henry S. "Grace Murray Hopper." In Encyclopedia on Computer Science, edited by Anthony Ralston and Edwin D. Reilly. 3d ed. New York: Van Nostrand Reinhold, 1993. A chronological listing of Hopper's achievements as a computer professional.

Williams, Kathleen Broome. Grace Hopper: Admiral of the Cyber Sea. Annapolis, Md.: Naval Institute Press, 2004. A thorough account of Hopper's life and career, describing how she brought the Navy into the computer age.

_______. Improbable Warriors: Women Scientists and the U.S. Navy in World War II. Annapolis, Md.: Naval Institute Press, 2001. Recounts how Hopper and four other women overcame discrimination to make significant contributions to naval science.

See Also
Tim Berners-Lee; Vinton Gray Cerf; Bill Gates; Kurt Gödel; Steve Paul Jobs; Akio Morita; John von Neumann; Alan Mathison Turing.

Related articles in Great Events from History: The 20th Century:
1901-1940: 1901-1925: Teletype Is Developed; Dec. 29, 1923: Zworykin Applies for Patent on an Early Type of Television; 1928: Bush Builds the First Differential Analyzer; 1935-1936: Turing Invents the Universal Turing Machine.

1941-1970: Aug., 1949: First Electronic Stored-Program Computer Is Completed; Mar. 31, 1951: UNIVAC I Becomes the First Commercial Electronic Computer; Apr., 1957: IBM Develops the FORTRAN Computer Language; May 1, 1964: Kemeny and Kurtz Develop the BASIC Computer Language.

1971-2000: Aug. 12, 1981: IBM Introduces Its Personal Computer; Nov. 20, 1985: Microsoft Releases the Windows Operating System; July 3, 1991: IBM and Apple Agree to Make Compatible Computers; Mid-1990's: Rise of the Internet and the World Wide Web; Jan. 1, 2000: Y2K "Crisis"; May 4, 2000: ILOVEYOU Virus Attacks Computers.