Sailing the Mathematics Seas: Grace Hopper and Technological Innovation

By Dyllan N. Cecil, Public History Center Fellow, Christopher Newport University, Class of 2017
Editor: Dr. Sheri M. Shuck Hall, Associate Professor of History, Director of the Public History Center, Christopher Newport University
Commodore Grace M. Hopper, United States Navy, Photograph, James S. Davis, 1984

Women’s roles in professional fields have fluctuated in the last century, due in part to the necessity for labor caused by World War I and World War II. The proportion of married women who also worked grew from 5 percent in 1890 to 60 percent by 1990. During World War II, in America specifically, women and minorities were granted employment opportunities in various fields including the military. One of these women, Grace Murray Hopper, pursued this chance.  Near the beginning of the war, she enrolled in the U.S. Navy Reserves, a popular course for women at the time. But she was able to use the skills from her regular employment as an Associate Professor of Mathematics at Vassar College to develop programming for the Mark I computer. In the decades that followed, Hopper became essential in advancing technology and molding it into what it is today. By the end of her career, Hopper conquered new territory in the digital realm, as well as making history by being one of the few women in the United States to achieve the rank of rear admiral. Hopper’s story demonstrated how America moved into the modern age, particularly through the contribution of many determined women. [1]

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Dr. Grace Hopper, director, Systems Research, Remington Rand, Library of Congress, Photograph, 1961

The Origin of a Legend

Grace became the first of Mary and Walter Murray’s three children on December 9, 1906. Residing in New York City, her family encouraged her, from an early age, to delve into her interests. She played with construction sets, loved reading, and took things apart to see how they worked. Both of her parents adored mathematics, and encouraged their children to be just as fascinated with the subject. Regardless of gender norms, they wanted all of their children to have the same educational opportunities. Additionally, Walter Murray had a poor circulatory system, forcing amputation of both legs and putting him at risk of a shorter life. This threat stimulated his desire for his daughters, as well as his son, to be educated so that they could support themselves if needed, a rare position for the early 20th century. Grace Murray studied at Schoonmakers School until age 16, when she applied to Vassar College in Poughkeepsie, New York. Due to a low score in Latin, they deferred her enrollment for a year, during which time she became a boarding student at Hartridge School, an institution that offered college preparatory classes. By 1924, Murray graduated from Hartridge and started at Vassar.[2]

Pursuing courses in mathematics and physics, and eventually majoring in both, Grace Murray utilized Vassar to develop knowledge in her life-long interests. Furthermore, her professors discovered Murray’s talent for teaching, as she quickly had students lining up for tutoring sessions. Of course, having such success as a tutor also demonstrated her strong grasp on the material. She graduated from Vassar in 1928 with honors, and even earned a fellowship to study at Yale University. By 1930, Grace Murray had a Masters degree and a new name, as she married Vincent Hopper, a graduate of Princeton who joined New York University’s faculty while he earned his Ph.D. from Columbia University. At the same time, Grace, now with the surname Hopper, began Yale’s Ph.D. program in mathematics and joined Vassar’s faculty a few months later. To put this course of events in perspective, between 1930 and 1934, only 16 percent of the 396 doctorates in mathematics were awarded to women. Even after earning her Ph.D., Hopper never stopped learning: she helped her husband conduct research for his dissertation in medieval number symbolism; she audited courses at Vassar on her own accord; and she enrolled in graduate courses at New York University in 1941, as she received a faculty fellowship through Vassar that allowed her to do so.  Unfortunately Vincent and Grace Hopper’s academic priorities affected their relationship, and they divorced in 1945, with Grace electing to keep her ex-husband’s name. [3]

Photograph taken from a Japanese plane during the torpedo attack on ships moored on both sides of Ford Island shortly after the beginning of the Pearl Harbor attack, U.S. Navy, Photograph, 1941

While Hopper earned accolade after accolade, her connection with the Navy grew. She then enlisted following the attack on Pearl Harbor in 1941. Here connection to the U.S. Navy had deep generational roots. As a very young child, Hopper spent time with her great-grandfather, Alexander Wilson Russell, a retired rear admiral who served with the Union Navy during the Civil War, as well as serving in the Mexican-American War. Additionally, Hopper’s family spent their summers at Lake Wentworth in New Hampshire, developing her skills with sailing. By the time the United States entered into World War II, Hopper was determined to follow family tradition. By 1942, Hopper was 35 years old and weighed 105 pounds, making her too old to enlist as well as weighing 20 pounds below the naval guidelines for her height. Additionally, Vassar would not grant her a leave of absence. She had to settle for teaching war preparedness courses for women at Barnard College. Yet she kept fighting, and by the end of 1943, Grace Hopper officially enlisted in the U.S. Navy Reserves.[4]

Office for Emergency Management, Office of War Information, Domestic Operations Branch, Bureau of Special Services, Enlist in the Waves Release a Man to Fight at Sea, National Archives and Records Administration, Poster, 1941-1945

The Emergence of Women in the Navy

Before 1942, there were no women in the military. Female nurses, of course, played a vital role in maintaining soldier care, but they received no official rank until 1942. The U.S. government understood that naval expansion was necessary for the country’s entrance into World War II, and the War Manpower Commission related that the U.S. Navy would not have enough manpower to sufficiently complete the expansion. Thus, it found ways to admit women for the sake of aiding the war effort. Following the attack on Pearl Harbor, the government began organizing women into four parts of the U.S. Armed Forces, starting with the Women’s Army Corps or WAC. By August of 1942, the Naval Reserves had been established, but with harsh regulations regarding female service. They were viewed as “temporary emergency personnel only, signed on for the duration of the war plus six months, and restricted to serving ashore within the forty-eight states.”[5] Additionally, there were limitations on the amount of women of color who could serve, with 1 out of every 36 WAVES being African American. While it was a grand step, it still limited female involvement and had no effect on the mindset of some of the older servicemen.[6]

The WAVES, a branch of the Naval Reserve, emerged as a popular way for women to make a difference. Short for “Women Accepted for Volunteer Emergency Service”, the WAVES featured 27,000 female members in the first year alone, with the end of the war seeing 8,000 officers and 80,000 enlisted. It was established in July 1942, and led by Mildred McAfee, who was appointed Naval Reserve Lt. Commander and who became the first female officer of the U.S. Navy. Eleanor Roosevelt showed her support for the organization by having the fashion label Mainboucher design the uniforms of both the WAVES and SPARS (the United States Coast Guard Women’s Reserve). So what did the WAVES do? Their roles were essentially limitless. They served as doctors, meteorologists, and pilots. They worked in clerical, communications, or technological capacities. But they were not authorized to participate in combat expeditions. Essentially, they were intended to take over men’s roles so that they could serve at sea.[7]

Opening of the U.S. Navy recruit camp for WAVES (Women Accepted for Volunteer Emergency Service) at Hunter College (Bronx Campus), New York City (USA), U.S. Navy, Photograph, 1943

Women volunteered for a plethora of reasons. Some wanted to feel like they were doing something meaningful, some wanted to work with a group of strongly patriotic people, and some were told by boyfriends that they would look good in the uniform. Regardless, they accomplished amazing feats. Only 100 of the 6,000 officers trained to be weather forecasters were women. These WAVES received such training due to extreme shortages at Naval Air stations as the war progressed. Eighty other WAVES underwent extensive training in twin-engine military planes to earn “gold wings as the nation’s first female military personnel to share noncombat flight duties with men.”[8]

Training for WAVES was a process, starting with general assembly at Hunter College in New York or Smith College in Boston. To receive more specialized training, like clerical work for instance, WAVES would move onto to other institutions like the Georgia College & State University in Milledgeville, Georgia. In Grace Hopper’s case, she studied at the Midshipmen’s School, a naval officer training program, at Smith College. She loved the structured experience, as she was coming from a life of racing between the colleges she taught at and between the colleges she took courses at, all the while attempting to develop her own research. At the Midshipmen’s school, Hopper earned the school’s highest ranking position, battalion commander, and graduated at the top of her class. Along with other family members, Hopper felt compelled to serve her country, and she, like her fellow WAVES sisters, would accomplish extraordinary feats. But it was Hopper’s achievement that revolutionized technology.[9]

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Howard Aiken and Grace Hopper, Grace Murray Hopper Collection, 1944-1965, Archives Center, National Museum of American History

A Revolution in Technology: the Mark I

After Hopper officially became a WAVE and completed her required training, she joined a program that maximized her skill set. In 1944, she began working with the Bureau of Ordnance Computation Project, housed at Harvard University. The project involved the development of the Mark I electronic computer. Measuring approximately 51 feet long and 8 feet tall, while weighing almost 5 tons, the Mark I was essentially a large calculator, computing the outcomes of complex physics problems. For instance, the Manhattan project (the program that researched and produced the first nuclear weapons) required the use of the Mark I. Specifically, the military needed calculations regarding radar, the atomic bomb’s implosion devices, and surveillance camera design.[10]

Sometimes referred to as the ASCC, the Mark I was called a “computer” because of the traditional definition of the word, meaning “a person who performed mathematical operations for large-scale projects.”[11] Howard Aiken originally presented the idea to IBM in the 1930s, but the project did not receive adequate development resources until it was gifted to Harvard by IBM president Thomas J. Watson Sr. and usurped as a naval project. The device appealed to the U.S. Navy Bureau of Ships because it could resolve complex mathematical problems, like gunnery and ballistic calculations, that usually required a big group of human computers to complete. Grace Hopper’s role was as a programmer, creating the code that would enable the Mark I to solve the problems. The user inserted the designated code, and the device would automatically produce the result. Furthermore, she also had the task of writing and publishing the instruction manual for the machine, requiring her to harvest all knowledge related to the Mark I. The manual became the first textbook for computer programming ever created.[12]

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Grace Hopper, Grace Murray Hopper Collection, 1944-1965, Archives Center, National Museum of American History

Hopper’s experience with the project was fascinating from the moment she arrived on campus. She was originally directed to the Navy Liaison office at the university, which was not easy to find. When she finally arrived there, the office employees, while having heard for the Bureau of Ships’ Computation project, had no idea where it was being conducted. When she entered at the basement of Cruft Laboratory after 2 P.M., she was met with an excited Howard Aiken. As she tried to explain her late arrival that day, he asked her where she had been for the last two months. Aiken, who enlisted in the U.S. Navy in 1941 and held the rank of commander by the time he met Hopper, had directed the Bureau of Personnel to send Hopper straight to Harvard. He felt that her Ph.D. allowed her to skip Midshipmen’s School. Clearly, his direction was not followed. After quickly showing her the Mark I and handing her a codebook, Aiken provided her a week to learn how to program the machine and to make it work. Although behind the others, Hopper’s extensive knowledge of mathematics and physics, talent with researching, and ability to clearly and effectively communicate made her an essential part of the team.[13]

Capt. Grace Hopper, then head of the Navy Programming Language Section of the Office of the Chief of Naval Operations, August 1976, U.S. Navy photo,

Hopper’s Legacy

Following the end of World War II, Hopper and Aiken endeavored to prove the legitimacy of the Mark I and the computer’s role in revolutionizing the way information could be calculated and redistributed. They published the manual, several articles, and a series of photographs that bolstered the Mark I’s reputation as well as their own. This was significant as IBM released their own account of the Mark I’s creation, even though the corporation had distanced itself from the project when it handed it over to Harvard. Hopper and Aiken’s publications refuted IBM’s claims of Aiken’s limited involvement in the computer’s development, among other discrepancies.  While IBM played a vital role in the project’s initial creation, their history appeared to give more credit to themselves in its success, rather than to the team at Harvard. If Hopper and Aiken had not released such compelling materials about their work, the Mark I would have been added to the list of calculators created by IBM engineers in the 1920s and 1930s.[14]

As her role in the Mark I’s development became clear to the world, Hopper joined even more ground-breaking projects. She believed that computers had endless possibilities and could be used by the general public. She left her position in 1949 and began working as a senior mathematician at Eckert-Mauchly Computer Corporation. By 1951, she began writing the code for UNIVAC I, the first mass-produced computer intended for commercial use. The device gained fame when it forecasted Eisenhower’s 1952 victory over Adlai Stevenson for the presidential election. Hopper developed FLOW-MATIC for the UNIVAC, the first compiler program to use English instead of numbers. Other scientists felt that only numerical codes should be used for computers, but Hopper believed in making such programs available to non-scientists. Using English would make it easier for others to delve into using computers. In 1959, a meeting for mathematics scholars was organized, with the result being COBOL or Common Business Orientated Language, another computer language using English words. COBOL was a direct result of FLOW-MATIC, and became so popular with both businessmen and the Defense Department that versions of it are still used today. In the years that followed, she essentially became a spokesperson for COBOL by traveling around to speak and teach the value of the language and computers in general.[15]

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Grace Hopper seated at the UNIVAC, Smithsonian Institute, Photograph, 1960

Hopper strongly pursued an education and a distinguished career at a time when it was somewhat unorthodox to do so. She earned her MA and Ph.D. at Yale, one of the most prestigious institutions in the United States, and went on to teach at Vassar and Barnard. Her desire to learn and research was limitless, explaining her over six decades of employment. Following a familial yearning to serve, she determinedly joined the U.S. Navy as soon as women were admitted. She emerged as such an essential asset to the military that she was recalled to serve numerous times after she retired, until her career spanned over 40 years and retirement became involuntary.

In 1983, Grace Murray Hopper received a promotion to the rank of commodore by special Presidential appointment; two years later her position was renamed to rear admiral. On November 22, 2016, President Barack Obama awarded Rear Admiral Grace Murray Hopper was the Presidential Medal of Freedom posthumously. In the ceremony, President Obama noted that: “If Wright is flight, and Edison is light, then Hopper is code.… From cell phones to [U.S.] Cyber Command, we can thank Grace Hopper for opening programming to millions more people, helping to usher in the information age and profoundly shaping our digital world.”[16]

Every year since 1971, the best young computer scientist receives the Grace Murray Hopper Award for Outstanding Young Computer Professionals by the Association for Computing Machinery (ACM). In October 2017, the Anita Borg Institute, in partnership with ACM, is hosting “The Grace Hopper Celebration of Women in Computing, the world’s largest gathering of women technologists.”[17] Her work on computing systems and programming increased the efficiency of military and business administration, and was the pioneer for the technology used today by the general public. She explored the worlds of mathematics and physics and resolved to make her findings easier for non-academics to understand. She was a researcher, a teacher, and a revolutionary. There is a strong chance that without her influence we would not have access to many of the devices that we take advantage of every day. Rear Admiral “Amazing” Grace Hopper’s legacy continues on as many women follow in her footsteps as leaders in the U.S. Navy, as well as the future generation of computer programmers.

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Commodore Grace M. Hopper, U.S. Naval Historical Center Online Library, Photograph, James S. Davis, 1984


[1] Claudia D. Goldin, “The Role of World War II in the Rise of Women’s Employment,” The American Economic Review 81.4 (1991): 741.

[2] Christy Marx, Grace Hopper: The First Woman to Program the First Computer in the United States (New York: the Rosen Publishing Group, Inc., 2004), 9-15; Kathleen Broome Williams, Grace Hopper: Admiral of the Cyber Sea (Annapolis: Naval Institute Press, 2012), 3-5.

[3] Williams, Grace Hopper: Admiral, 11-12, 15-18.

[4] Marx, Grace Hopper: the First Woman, 12; Williams, Grace Hopper: Admiral, 19-22.

[5] Williams, Grace Hopper: Admiral, 19.

[6] Marie Bennett Alsmeyer, “Those Unseen, Unheard Arkansas Women: WAC, WAVES, and Women Marines of World War II,” Minerva 12.2 (1994): 15; Williams, Grace Hopper: Admiral, 19; “WWII and WAVES (Women Accepted for Volunteer Emergency Service),” Armed Forces History Museum,

[7] Alsmeyer, “Those Unseen,” 15; Cecilia Rasmussen, “Those Flying Waves of WWII,” Sea Classics 35.12 (2002), 10; “WWII and WAVES,” Armed Forces History Museum.

[8] Rasmussen, “Those Flying Waves,” 10.

[9] Kurt W. Beyer, Grace Hopper and the Invention of the Information Age (Cambridge: the MIT Press, 2009); J.M. Lewis, “WAVES Forecasters in World War II (with a Brief Survey of Other Women Meteorologists in World War II),” Bulletin of the American Meteorological Society 76.11 (1995): 2187; Rasmussen, “Those Flying Waves,” 10; Williams, Grace Hopper: Admiral, 22-23.

[10] “About,” the Mark I Computer at Harvard University, Harvard University,; Susan Casey, Women Invent: Two Centuries of Discoveries that Have Shaped Our World (Chicago: Chicago Review Press, 1997), 14; “IBM’s ASCC Introduction,” IBM Archives, IBM,; V Rajaraman, “Grace Murray Hopper- Programming Pioneer,” Resonance 6.2 (2001): 2-3; Williams, Grace Hopper: Admiral, 25, 28.

[11] “About,” the Mark I Computer.

[12] “About,” the Mark I Computer; “Function,” the Mark I Computer at Harvard University, Harvard University,; “Manual,” the Mark I Computer at Harvard University, Harvard University,; Rajaraman, “Grace Murray Hopper,” 2-3; the Staff of the Computation Laboratory, A Manual of Operation for the Automatic Sequence Controlled Calculator (Cambridge: Harvard University Press, 1946), 98; Williams, Grace Hopper: Admiral, 27-28.

[13] Beyer, Grace Hopper and the Invention; Williams, Grace Hopper: Admiral, 25-26.

[14] Beyer, Grace Hopper and the Invention.

[15] Beyer, Grace Hopper and the Invention; Peter H. Lewis, “Armchair View of Election,” New York Times, Nov. 3, 1992, C12; Rosario M. Rausa, “In profile: Grace Murray Hopper,” Annapolis 6.3 (1992): 58

[16] April Grant, “Computer Science Legend, Rear Adm. Grace Hopper, Posthumously Receives Presidential Medal of Freedom” Story Number: NNS161122-19, Release Date: 11/22/2016 4:32:00 PM, accessed on 21 August, 2017 at

[17] See

Works Cited

Alsmeyer, Marie Bennett. “Those Unseen, Unheard Arkansas Women: WAC, WAVES, and Women Marines of World War II.” Minerva 12.2 (1994): 15.

Armed Forces History Museum.”WWII and WAVES (Women Accepted for Volunteer Emergency Service).”

Beyer, Kurt W. Grace Hopper and the Invention of the Information Age. Cambridge: the MIT Press, 2009.

Casey, Susan. Women Invent: Two Centuries of Discoveries that Have Shaped Our World. Chicago: Chicago Review Press, 1997.

Goldin, Claudia D.  “The Role of World War II in the Rise of Women’s Employment.” The American Economic Review 81.4 (1991): 741-756.

Harvard University. “About.” the Mark I Computer at Harvard University.

Harvard University. “Function,” the Mark I Computer at Harvard University.

Harvard University. “Manual,” the Mark I Computer at Harvard University.;

IBM Archives. “IBM’s ASCC Introduction.” IBM.

Lewis, J.M. “WAVES Forecasters in World War II (with a Brief Survey of Other Women Meteorologists in World War II).” Bulletin of the American Meteorological Society 76.11 (1995): 2187-2202.

Lewis, Peter H. “Armchair View of Election.” New York Times, Nov. 3, 1992, C12.

Marx, Christy. Grace Hopper: The First Woman to Program the First Computer in the United States. New York: the Rosen Publishing Group, Inc., 2004.

Rajaraman, V. “Grace Murray Hopper- Programming Pioneer.” Resonance 6.2 (2001): 2-3.

Rasmussen, Cecilia. “Those Flying Waves of WWII.” Sea Classics 35.12 (2002), 10.

Rausa, Rosario M. “In profile: Grace Murray Hopper.” Annapolis 6.3 (1992): 58.

The Staff of the Computation Laboratory, A Manual of Operation for the Automatic Sequence Controlled Calculator. Cambridge: Harvard University Press, 1946.

Williams, Kathleen Broome. Grace Hopper: Admiral of the Cyber Sea. Annapolis: Naval Institute Press, 2012.