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ThinkStock/Erin McCarthy
ThinkStock/Erin McCarthy

What’s the Deal with Those Last 4 Digits on ZIP Codes?

ThinkStock/Erin McCarthy
ThinkStock/Erin McCarthy

Almost everyone knows their five digit ZIP code, and probably a few others within their city, but what’s up with the extra four digits you sometimes see on mail?

Let’s start with those first five digits you’re already familiar with. In the early 1960s, the U.S. Postal Service could see that the old Postal Delivery Zone System was outdated and couldn’t handle increasing mail volume and urban and suburban expansion. To keep the mail moving efficiently, the Postal Service introduced the Zone Improvement Plan (ZIP) in 1963. A five-digit code was assigned to every address in the country—the first designated a broad geographical area or group of states (“1,” for example covers New York, Pennsylvania, and Delaware), the next two designated a region or large city in that area (“91” covers Philadelphia) and the last two represented a smaller delivery zone or group of delivery addresses in that region. 

Over the next two decades the ZIP system became strained, too, and in 1983, the Postal Service expanded it to create the ZIP+4 system, tacking on an extra four digits at the end of the old codes. These new digits identified an area—like a group of apartments or office buildings—or a high-volume mail receiver within a five-digit delivery zone to help with mail sorting and delivery. The sixth and seventh digits of a ZIP+4 indicate a “delivery sector,” like a group of streets, P.O. boxes, a group of buildings, or even a single high-rise building. The eighth and ninth digits designate a “delivery segment,” like a specific side of a street, a floor in an office or apartment building, or a specific department within a large office. 

Getting the public on board with the regular old ZIP codes had been hard enough (some people were annoyed they had another number to remember in addition to telephone area codes and their Social Security number, while others thought that being represented by a number was dehumanizing and un-American), so the ZIP+4 never caught on with people. Fortunately, around the time the expanded codes were implemented, the technology available to the USPS meant that people didn’t have to remember or use the full code. Automatic mail sorting systems apply a Postnet barcode to mail items that corresponds to a full code, and multi-line optical character readers can determine the correct ZIP+4 from the barcode and written address. 

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Big Questions
How Are Royal Babies Named?
Jack Taylor, Getty Images
Jack Taylor, Getty Images

After much anticipation, England's royal family has finally received a tiny new addition. The birth of the Duke and Duchess of Cambridge's second son was confirmed by Kensington Palace on April 23, but the name of the royal newborn has yet to be announced. For the heir to the British throne and his wife, choosing a name for their third child—who is already fifth in line to the throne—likely won't be as easy as flipping through a baby name book; it's tradition for royals to select names that honor important figures from British history.

According to ABC WJLA, selecting three or four names is typical when naming a royal baby. Will and Kate followed this unwritten rule when naming their first child, George Alexander Louis, and their second, Charlotte Elizabeth Diana. Each name is an opportunity to pay homage to a different British royal who came before them. Some royal monikers have less savory connotations (Prince Harry's given name, Henry, is reminiscent of a certain wife-beheading monarch), but typically royal babies are named for people who held a significant and honorable spot in the family tree.

Because there's a limited pool of honorable monarchs from which to choose, placing bets on the royal baby name as the due date approaches has become a popular British pastime. One name that keeps cropping up this time around is James; the original King James ruled in the early 17th century, and it has been 330 years since a monarch named James wore the crown.

If the royal family does go with James for the first name of their youngest son, that still leaves at least a couple of slots to be filled. So far, the couple has stuck with three names each for their children, but there doesn't seem to be a limit; Edward VIII, who abdicated the throne to George VI in 1936, shouldered the full name of Edward Albert Christian George Andrew Patrick David.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

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Big Questions
Why Does the Queen Have Two Birthdays?
CHRIS JACKSON, AFP/Getty Images
CHRIS JACKSON, AFP/Getty Images

On April 21, Her Majesty Queen Elizabeth II will turn 92 years old. To mark the occasion, there are usually a series of gun salutes around London: a 41 gun salute in Hyde Park, a 21 gun salute in Windsor Great Park, and a 62 gun salute at the Tower of London. For the most part, the monarch celebrates her big day privately. But on June 9, 2018, Her Majesty will parade through London as part of an opulent birthday celebration known as Trooping the Colour.

Queen Elizabeth, like many British monarchs before her, has two birthdays: the actual anniversary of the day she was born, and a separate day that is labeled her "official" birthday (usually the second Saturday in June). Why? Because April 21 is usually too cold for a proper parade.

The tradition started in 1748, with King George II, who had the misfortune of being born in chilly November. Rather than have his subjects risk catching colds, he combined his birthday celebration with the Trooping the Colour.

The parade itself had been part of British culture for almost a century by that time. At first it was strictly a military event, at which regiments displayed their flags—or "colours"—so that soldiers could familiarize themselves. But George was known as a formidable general after having led troops at the Battle of Dettingen in 1743, so the military celebration seemed a fitting occasion onto which to graft his warm-weather birthday. Edward VII, who also had a November birthday, was the first to standardize the June Trooping the Colour and launched a tradition of a monarchical review of the troops that drew crowds of onlookers.

Even now, the date of the "official" birthday varies year to year. For the first seven years of her reign, Elizabeth II held her official birthday on a Thursday but has since switched over to Saturdays. And while the date is tied to the Trooping the Colour in the UK, Commonwealth nations around the world have their own criteria, which generally involve recognizing it as a public holiday.

Australia started recognizing an official birthday back in 1788, and all the provinces (save one) observe the Queen's Birthday on the second Monday in June, with Western Australia holding its celebrations on the last Monday of September or the first Monday of October.

In Canada, the official birthday has been set to align with the actual birth date of Queen Victoria—May 24, 1819—since 1845, and as such they celebrate so-called Victoria Day on May 24 or the Monday before.

In New Zealand, it's the first Monday in June, and in the Falkland Islands the actual day of the Queen's birth is celebrated publicly.

All in all, just another reason it's great to be Queen.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

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