It was this day in 1963 that zip codes as we know them today were introduced to the U.S. I know your internal trivia arsenal is lacking in ZIP code facts, so we will remedy that today.

1. ZIP stands for "Zone Improvement Plan." It was trademarked by the United States Postal Service for a while, but it has since expired, so you can use "ZIP" guilt-free. Not that you were feeling guilty about it in the first place.

2. The first three numbers of the code represent a USPS sectional center facility (SCF). The last two numbers further narrow down the location, but in some cases they are continuations of two-digit zip codes that were issued to big cities in 1943. For instance, the Minneapolis ZIP code used to be 16, so 55416 is now part of Minneapolis.

3. 90210 is, yes, Beverly Hills. Another good one: 12345 is General Electric in Schenectady, N.Y.

4. Robert Moon developed the ZIP code idea while working as a postal inspector in Philadelphia, and although he proposed using just three digits, he is still considered the father of the ZIP code. He died in 2001, by the way, and his ZIP code at that time was 34748 "“ Leesburg, Fla.

5. Mr. ZIP, AKA Zippy, was a cute little guy used in the '60s and '70s to promote the use of ZIP codes. He was drawn by Harold Wilcox, the son of a postman. But don't get the idea that a four-year-old kid was at home doodling and his proud dad brought the scribble into work - nope, Harold Wilcox was an art director working for the Cunningham and Walsh advertising agency. He drew the cartoon to look like a little kid had drawn it, though, and originally named him Mr. P.O. Zone.

6. Ethel Merman recorded a song to the tune of "Zip-a-dee-doo-dah" to promote the new ZIP codes.

7. Places with their own zip codes include the White House (the one for the president and his family to receive personal mail is secret), the World Trade Center (prior to Sept. 11), Saks Fifth Avenue in New York, and most recently, Dodgertown in California. Smokey Bear also received his own code at the height of the "Only you can prevent forest fires" campaign in 1964: 20252.

8. The wealthiest ZIP code in the U.S. isn't 90210, nor is it even in the vicinity. According to Forbes magazine, the two zip codes tied for first are 07620 - Alpine, N.J. - and 33109 - Fisher Island, Fla.

9. ZIP + four was added in 1983.

10. You can get instructions for looking up zip codes and seeing their boundaries here. It's strangely addicting and kind of like finding shapes in clouds... or not. I think I need to get outside and enjoy nature more.