#5 Grace Hopper

Computer Scientist, United States

1906-1992

Grace Hopper is credited with developing the first computer compiler for a programming language. She also conceptualized the idea of machine-independent programming and developed COBOL, one of the first modern programming languages. She popularized the presently most common term “debugging,” for fixing computer errors. She also became one of the first female Admirals in U.S. navy. Due to her achievements, the U.S. Navy ship USS Hopper is named for her, as was the Cray XE6 "Hopper" supercomputer.

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#4 Katherine Johnson

Space scientist, United States

1918- Present

Katherine is an African-American physicist who is responsible for calculating the trajectory for 1969 Apollo 11 flight, which landed the first ever humans, Neil Armstrong and Buzz Aldrin on the moon. She made significant contributions to America's aeronautics and space programs with the early application of digital electronic computers at NASA.  

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