By bringing them home (my dad) and giving them to their kids for use as book marks, scrap notes, etc etc. I still sometime come across one hidden in an old book

By bringing them home (my dad) and giving them to their kids for use as book marks, scrap notes, etc etc. I still sometime come across one hidden in an old book or (physical) file somewhere. At school (1979) I used them in computer classes at school, where they were sent down the road to an insurance company that actually had a computer, and we got our compilation errors back the next week. My programs weren't long enough for serious card-deck disasters. But I completely agree with the TFA point that the very slow iteration makes you check things very carefully