But one curious man has sparked a discussion on social media after asking whether the 'black and orange streaks' on his letters ... known as Royal Mail 4-State Customer Code (RM4SC), have an ...

A member of Royal ... P' mark on letters. It comes following a flurry of panic among pet owners. Rumours had been spreading on social media that the cryptic symbol was a secret code used by ...

A Royal Mail worker has finally revealed what the 'P' on your letters means. Plenty of speculation has swirled, with some people guessing it could even be a code for thieves targeting pets.