I learned Fortran with punch cards and a teletype. We would hand a program deck (a stack of cards) to the machine operator and in a few minutes our printed out

I learned Fortran with punch cards and a teletype. We would hand a program deck (a stack of cards) to the machine operator and in a few minutes our printed output and the program deck would appear in an alphabetized set of bins. The physical stack of cards was the only storage medium for the code. Check your debug output, modify (or insert) a few cards and repeat. Don't forget the JCL (job control language) on the first card. That is how you tell the mainframe what resources your code needs and how to run it. If you get that wrong nothing happens. We were taught to draw a diagonal line across the top edge of the deck of cards so you could quickly put the deck back together correctly if it was dropped.