A postal code is a five digit code used to help postal services deliver mail and packages. Here's what the numbers mean and how they determine yours.

Norfolk, Va. – Effective immediately, anyone sending mail to Navy mobile units must use a nine-digit ZIP code to ensure delivery, according to a message released by Secretary of the Navy Ray Mabus.

The U.S. Postal Service began using the five-digit ZIP code in 1963. In recognition of the anniversary, we've examined the list of more than 40,000 ZIP codes and highlighted a few that deserve ...