Women Were First Computer Programmers

Sunday, March 25, 2012

In this excerpt from "The Computer Boys Take Over," historian Nathan Ensmenger explains that the first computer programmers were women because managers expected programming to be low-skill clerical work. They were wrong: The job required skill and ingenuity and these women persevered.

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P> Goldstine and von Neumann spelled out a six-step programming process: (1) conceptualize the problem mathematically and physically, (2) select a numerical algorithm, (3) do a numerical analysis to determine the precision requirements and evaluate potential problems with approximation errors, (4) determine scale factors so that the mathematical expressions stay within the fixed range of the computer throughout the computation, (5) do the dynamic analysis to understand how the machine will execute jumps and substitutions during the course of a computation, and (6) do the static coding.

The first five of these tasks were to be done by the "planner," who was typically the scientific user and overwhelmingly was frequently male; the sixth task was to be carried out by coders.

Coding was regarded as a "static" process by Goldstine and von Neumann -- one that involved writing out the steps of a computation in a form that could be read by the machine, such as punching cards, or in the case of the ENIAC, plugging in cables and setting up switches. Thus, there was a division of labor envisioned that gave the highest-skilled work to the high-status male scientists and the lowest-skilled work to the low-status female coders.

As the ENIAC managers and coders soon realized, however, controlling the operation of an automatic computer was nothing like the process of hand computation, and the Moore School women were therefore responsible for defining the first state-of-the-art methods of programming practice.

Programming was an imperfectly understood activity in these early days, and much more of the work devolved on the coders than anticipated. To complete their coding, the coders would often have to revisit the underlying numerical analysis, and with their growing skills, some scientific users left many or all six of the programming stages to the coders. In order to debug their programs and distinguish hardware glitches from software errors, they developed an intimate knowledge of the ENIAC machinery.

"Since we knew both the application and the machine," claimed ENIAC programmer Betty Jean Jennings, "as a result we could diagnose troubles almost down to the individual vacuum tube. Since we knew both the application and the machine, we learned to diagnose troubles as well as, if not better than, the engineers." In a few cases, the local craft knowledge that these female programmers accumulated significantly affected the design of the ENIAC and subsequent computers.


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Nathan Ensmenger is Assistant Professor of the History and Sociology of Science at the University of Pennsylvania.

For more information:

The Computer Boys Take Over: Computers, Programmers, and the Politics of Technical Expertise (History of Computing):

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Many folks regard a 19th century English woman, Ada Lovelace, as the first programmer ever. She
worked with Charles Babbage on his never-built proto-computers. The programming language Ada is named after her.

She also has her own day where people are encouraged to blog about the achievements of women in technology which I love!

My mother, a '43 Penn graduate talented in math, worked on this project during the war. She was the one responsible (along with a military escort) for bringing the work from Penn to Aberdeen each week.

I wish I could 'like' posts on here, this post definitely deserves one. I'm glad we have the opportunity to raise awareness of women's important contributions to the world we have today.