Grace Hopper

 “Amazing Grace”

“A ship in port is safe, but that’s not what ships are built for.”

—Grace Murray Hopper

When Rear Admiral Grace Murray Hopper retired from the Navy at the age of 80, she was the nation’s oldest active duty officer. She had made a career out of swimming against the current and finding new ways to solve problems.

She got her start in computing in the 1940s. Hopper was a tenured mathematics professor at Vassar College, and she was bored. She had no children and her marriage and job were unsatisfying. When the Japanese bombed Pearl Harbor in 1941, America’s entry into World War II gave her an exit strategy.

Hopper joined the war effort. Over the next year and a half, she resigned her faculty position, divorced her husband, and at age 36 joined the U.S. Navy, graduating first in her class in 1944.

Expecting to get a cryptology assignment, she was instead sent to Harvard’s Cruft Laboratories.  Hopper was the third person to join Howard Aiken’s research team for the Mark computer series.

While the Mark I initially was used for research in physics and astronomy, soon the Navy had commandeered it for problems associated with magnetic fields, radar, and a top-secret equation from scientists at Los Alamos Laboratories in New Mexico concerning the implosion of the atomic bomb.

The clickety clack of the computer’s thousands of electromechanical parts was said to sound like a roomful of ladies knitting. Hopper was instrumental to keeping the Mark I running—not least of which the day she repaired the machine by removing an actual moth from inside its components, “debugging” the computer in the truest sense.

The visionary computer programmer was appointed to the Harvard faculty as a research fellow, but in 1949 she left to join the newly formed Eckert Mauchly Corporation, whose founders built ENIAC, one of the first fully electronic digital computers.

There, in 1953, she made her best-known contribution with the invention of the compiler, a program that translates instructions in plain English into the language of the target computer. Her work led to the development of the computer language COBOL, which for a time was the most widely used computer language in business, broadening the reach and accessibility of the technology.

Grace Hopper died in her sleep in 1992 and was buried with full Naval honors at Arlington National Cemetery.