In the days before digital computers, "computers" were human (as @Halpin just noted in a convo with me)
People doing calculations by hand
A large chunk of these human computers were women
Indeed, so *many* were women that ...
"... one contractor of the Applied Mathematics Panel used the term 'kilogirl' to refer to 1,000 hours of female calculation work. Another astronomer spoke of 'girl-years' of work."
I wrote about this for Smithsonian magazine a few years ago: https://www.smithsonianmag.com/science-nature/history-human-computers-180972202/