Re: APO vs FPO


What IS the difference between APO & FPO?  I know APO stands for Air Post Office.  What’s FPO?  Flying Post Office?  F*&%ing Post Office? Fun Post Office?  Frilly Post Office?  Are all APO’s interchangable with FPO’s?  I’ve done some online shopping, and they won’t mail to an APO, so I have them send stuff to my mom, and then make my mom send the stuff here…. It would be nice to learn a new APO vs FPO trick & get my stuff just sent directly.
What is an FPO?