Add Yahoo as a preferred source to see more of our stories on Google. Most Americans know their ZIP code by heart. They type it into online forms, scribble it on envelopes and memorize it as part of ...

The humble ZIP Code shows up in all kinds of surprising places. Planet Money looks at how it was born, how it transformed the mail and talks to one researcher who argues that it's gone too far. The ...

Today marks the 50th anniversary of the Zone Improvement Plan, the network of ZIP codes we use for everything from mail delivery to credit card security. The U.S. Postal Service began using the ...

Most Americans know their ZIP code by heart. They type it into online forms, scribble it on envelopes and memorize it as part of their address. But not everyone knows the original meaning of the term.