Friday Find: How the mail works

It's the season of long Post Office lines, crammed-full mailboxes, and Sunday package deliveries. I will be mailing a lot of packages this year, what with being so far from family, and I'm also doing holiday cards for the first time since 2010 (as I mentioned).  

As I stood in line at the Post Office the other day in order to buy some more stamps and drop off about 100 cards (I didn't want them to clog up a mailbox, and I needed international stamps), I had time to ponder how on earth all these cards would wing their way across the country and around the globe, and get where they needed to go in just a few days. 

From previous work in marketing and direct mail, I'm familiar with mail fulfillment centers where thousands of pieces of mail are put together, grouped by zip code, and delivered to the Post Office, but I had trouble picturing what happened on the other side, with every day mail that's not organized, with addresses that are hand-written, and envelopes that vary in size. I poked around and came across this explanation on the USPS website explaining how letters are scanned, coded, sent off, and then collated at the destination, in order, for the letter carrier to deliver (something else I've always wondered). I have to admit, I am fascinated and impressed by this process!