On July 1, 1963, the U.S. Post Office Department introduced the ZIP code program to get a handle on the heaping surplus of mail. Today, those five digits represent much more for American society. Back ...

This post may contain links from our sponsors and affiliates, and Flywheel Publishing may receive compensation for actions taken through them. A letter without a ZIP code may not reach its intended ...

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 ...

Everyone knows the ZIP code 90210—but what about these other notable codes around the country? The Zone Improvement Plan, otherwise known as the ZIP code, is the network of postal codes the U.S.

What is a postal code? A postal code, also sometimes called a post code, is a series of letters and/or digits included in postal addresses to facilitate the sorting of mail. Postal codes are usually ...