COMPUTER MEMORIES, Chapter 70

A COMPUTER PROGRAM MIMICS THE IBM ROOM
Use your imagination a little and you can see how, before computers, the action and interaction of man and the IBM-EAM machines in the “IBM room,” was much like the functions performed in the years since, by a computer program. That is, the operational flow sheet directed a person to gather punched cards (memory) that contained payroll information, put the cards in a machine that would perform needed arithmetic functions, then put the cards in a machine that would sort them into a specific order, now present the cards to a printer that would create the final paycheck. Then place a set of cards in the proper file as needed for historical purposes and government reports, and another set in a file as the base data for next week’s paycheck. Each operation, which might be called a “subroutine,” was directed by the operational flow sheet, which looks much like the outline of a stored program in a computer.

All right, it takes a lot of imagination, not just a little, but for example, the movement of payroll data from machine to machine, the actions of the operators, and the creation of files of cards for other accounting purposes, resulted in exactly the same paycheck and reports that would be created by a computer, being controlled by a stored program.