In high school - BASIC class - we had to build a program to let a user input an address.
I took the input for the ZIP code as a string, and the teacher 'corrected' me because ZIP codes were numbers, not letters. I said "if I starts with 0, that would be lost".
"ZIP codes don't start with 0," she replied.
"Umm... yeah they do." I pull out a copy of my New Zork Times from Infocom, located in MA, and their ZIP started with 0.
It was only years later I learned the ZIP code system didn't even start until the 60s, and she'd likely grown up without it even being a thing, so I (retroactively) cut her some slack. Really didn't think anyone in the US could not know that in 2017 but... I still run in to people who don't. And... it's probably less important today (what with email and ebills and whatnot), so I'll cut everyone else some slack too... :)
