The term POST; ARMOUR is composed of two words. The first word, POST, is a four-letter word meaning MAIL or letters. The second word, ARMOUR, is an eight-letter word meaning protective covering or defense. Together, the two words can be interpreted to mean the protection of MAIL or letters. This could refer to the use of physical armor to protect MAIL carriers from harm, or it could refer to the use of encryption and other security measures to protect the contents of MAIL from being accessed by unauthorized individuals.