A quick overview and explanation of punched cards. Most surviving equipment is in museums, but I managed to borrow and play with a Hollerith hand punch - see it in operation!
That brought back memories Richard. The punctuation mark that I remember was 0/3/8 for a comma. When you used them for programming it was recommended to add a sequence number to the card on the RHS. This was needed in case a tray of cards containing a program got dropped on the floor. You would then need to run the recovered pack through the sorter to get them back in the correct order.
I didn't use punch cards, but was an ICL data processing engineer who looked after the punches, verifiers, sorters, etc. The technology back then was amazing for the time. A few years ago it was only by accident that I met the training officer who lent me the punch, and loads of training manuals which I scanned to pDF for him. Amazing... but I wouldn't want to go back to 'the good old days'.
