Answers (2)
It is a code used by the post offices for mail addresses, the zip code stands for place or part of a place. (you put a zip code on a letter to help the post office to sort mail and send it to the correct address)
for example 03801 is the the zip code for portsmouth in new hampshire.
also a big city has more then one zip code usually.
-kind of confusing but i hope you get it ^^