Removing the necessity of city and state on envelopes and packages, and leaving it to a formulaic five-digit zip code improved accuracy of mail sorting, and quite frankly, greatly improved the speed ...

After the 5-digit ZIP code gets the mail to your local post office, the "plus 4" code gets it to your neighborhood. "Do you have to write it on your letters?" asked WCCO reporter Jason DeRusha.

Many of us use the same 4-digit code for everything. Phones, credit cards, and even padlocks. A new report has shown that millions of people are using identical PIN codes, making phones and bank ...

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 ...

How is it that a simple five-digit ZIP code provides any insight into who you are? After reading my recent article on how stores often ask for our ZIP codes to build marketing profiles, Michael ...