"Computer" used to be a job title. Quite a lot of effort went into parallelizing algorithms so they could be dispatched to a (large) room full of people (usually men) with desktop calculators who would each play CPU.
One of my college professors had a summer job as "computer" at Grumman. Reading Neville Shute's autobiography, Slide Rule, will give a flavor of that era. One of Mr Shute's titles was that of "Chief Calculator," and he was a noted aeronautical engineer.
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