Also, "everybody" knows their zip-code/postal-code is mostly an American/British thing, I still remember my British former boss asking me about my zip-code about 20 years ago (I live in Romania, we were implementing the first google-maps-based mashup in this country) and me answering that I have no idea, and that no-one around these parts really knows his/her postal-code. We do know our address, though, or used to, before we had smart-phones.