One line of computer programming, whichever language you were using. Up to 80 characters wide, same as the card's width.
I remember. And we loved it. No home computers, no cellphones, no internet. Mid 70's in my case.
Guy Steele would like you show you his one-card wonder for the #IBM1130 - "the ugliest program I ever wrote" - with full disassembly and explanation.
https://www.infoq.com/presentations/Thinking-Parallel-Programming/
Thank you, Ed! I will add the video you linked to my ever growing Tabs list, to be processed.
I found a nice image showing how each of the possible characters was encoded into a card, it's here: http://www.columbia.edu/cu/computinghistory/026-card.jpg
Some characters are one single punch hole (each character occupies one vertical column, out of the 80 possible in the card), some use two punch holes, which combined represent the character.
I was looking at images and found a nice one of the IBM Model 29 card punch, which is the one I personally worked with to create my first programmes in first year Uni classes. It was a solid, well built, last forever machine.
