Psst, your ZIP code is telling all your secrets. In fact, so much is hidden in that short string of digits at the end of your address – we're talking pride, discrimination and marketing gold. Starting with a bulging wartime mail sack and ending with a cup of tea down an Irish country road – this is the winding journey of the postal code.

We trace the unexpected backstories of everyday things – things that have traveled the world, by force, by chance, or by choice. How did this item or idea change as it moved through different cultures and eras on its way to you? And what surprising truths does its story reveal about our world today?