Human computers had to add large numbers by hand on chalkboards
This odd job of the past might be confusing to think about at first. After all, there have been types of calculators, or more specifically adding machines, since the 17th century. Still, these machines were no good on a large scale. So, up until the late 1950s, people used to work as human calculators.
This job was particularly done by women. They had to work all day on mathematical calculations that used both small and large figures by hand on huge chalkboards or else on their desks with pen and paper. Men in this job were mostly science students that took this opportunity to get started in the field.