we used a stack of punch cards.

I never used punch cards. On the first computers I used, the HP-3000 and the PDP-8/e, though the latter did have a card reader attached, were time-sharing and had multiple ASR-33 teletypes (image) for I/O. I also saved my programs on paper tape.

While punched cards (to control looms) date from around the early 19th century, punch card readers date from the late 19th century, pre-dating modern, digital computers by about 50 years. Herman Hollerith, who founded the company now known as IBM, sold the first readers to the US government to help tabulate data from the 1890 census. (You can see some great pictures here and read more about it.) IBM sold tabulating equipment to a lot of different governments including the Third Reich in Germany (link).

Ceci n'est pas un seing.