I recently completed the training to be a city carrier for the USPS. After seeing the back end of the operation, I can tell you it is an astounding organization. Like most of you probably do, I just took for granted getting mail in my mailbox at my home every day. Now, it boggles my mind the volume of mail which is handled so efficiently by so many different people.
There are many different jobs at the USPS and carrier is one of the most under appreciated of those jobs. Trust me when I tell you, your carrier is working his/her butt off to delivery your mail to you daily.
If you get the chance, show your carrier your appreciation. Offer a bottle of water in the heat - a cookie (cause most of them don't take time to eat) - a Christmas card - anything which might show your appreciation will be remembered and will brighten your carriers day.