L.A. State First 1620
Prentiss was a student at L.A. State College and was studying computers there. The computer they were working on was an IBM computer called the 1620.
The 1620 used paper tape, or in the models I worked on, punched cards as their main source of input.
They also had a console typewriter which could serve as a rather slow input/output device.
More often, output was punched to cards and the cards were taken to some other machine where their contents were printed.
Since neither Dave nor I were students at L.A. state we were not really supposed to use their computer, but no one really checked and we looked and acted like the other legitimate students.
On that first occasion, Dave showed me how things were done. A program was prepared on punched cards, using a key-punch machine: one could type on a keyboard and what one typed was punhed into cards.
We then stood in line with the other students, waiting for our turn to use the computer. When our turn came, we fed our cards into the card reader; the computer read them and punched or typed its output. Unless, of course, ones program contained an error, in which case a Check stop light on the console came on, and you had to decipher your mistake from the other console lights.
Dave proceeded to write a program to compute the formulae I had been playing with. Here is some of the output:
