Punch cards! 80 card columns. I was one of the guys who removed the interpreter (read the cards and converted the info on the cards to data for the mainframe computer) from the Supply computer room at my squadron when punch cards finally became a thing of the past. That thing was HEAVY! It was obsolete as hell but we got our bar-code readers from the lowest bidder and they kept failing. I think that was in 1988.
As an AFROTC cadet in summer of 1981 I spent two weeks at Chanute Air Force Base with the base main frame, which was essentially the supply computer. Not only punchcards, but tape drives! I got tasked to write up a procedure for cleaning the tape drives. Something else Youngsters will never do.