The familiar five-digit number was part of a nationwide effort to modernize the mail.

It's very easy to chalk up certain facets of our lives to just being "the way it's always been." From daylight savings time to time zones, most of us don't even give a second thought to the meaning ...

Hanna Horvath is a CERTIFIED FINANCIAL PLANNER™ and Red Venture's senior editor of content partnerships. Fox Money is a personal finance hub featuring content generated by Credible Operations, Inc.