What makes you completely useless in life

There are random facts, there are animal facts, there are wonderful facts, and there are historical facts. And then, perhaps least importantly, there are useless facts—or facts that you will absolutely, never, ever need to know. From how long it takes your fingernails to grow to which state capital is the only one without a McDonald's, these are the useless facts you'll love to learn, and then try to find a reason to use.

There are four kings in every deck of cards. And while they all look similar, the king of hearts is the only royal fellow who doesn't have a mustache. According to The Guardian, the so-called "suicide king" (who earned his name because it looks like he's stabbing himself in the head with a sword), wasn't always bare-faced. He mistakenly lost his facial hair in a redesign.

The English language is full of idiosyncrasies, and the word dreamt is one of them. According to Oxford Dictionaries, "dreamt" (and its variations, such as "undreamt") is the only word in the English language that ends with the letters "mt."

If you take a look, you'll see that one and six are on opposite sides of the cube (1+6=7), as are two and five (2+5=7), and three and four (3+4=7).

The next time you're wearing a pair of jeans, take a look at the pockets. Do you see those little metal studs at the corners? They're not just there to add some extra pizzazz to your pants, they actually have a purpose. Rivets, as they're called by Levi Strauss, are placed on certain spots to add extra support where the denim is more likely to wear out and rip.

Unless you live in the United Kingdom where it's proper to write 101 as "one hundred and one," there is no number from 1 to 999 that includes the letter "a" in its word form. One, two, three, four, five, six… twenty, thirty, forty, fifty, sixty… You can keep going, but you won't find the first letter in the alphabet until you hit "one thousand."

We're not all as physically active as we should be, and it can be hard to fit workouts into our daily routine. On the other hand, when it comes to relieving ourselves (yes, we mean going to the bathroom), we can't really deny our regular need to do our business. That's why, according to a 2017 study by British non-profit UKActive, adults spend an average of three hours and nine minutes on the toilet each week, but only spend around one hour and 30 minutes being physically active during that same time span. Perhaps it's time to figure out how to exercise while using the restroom?

Cats can jump surprisingly high, slip through the tightest spaces, and seemingly have nine lives. But there's one thing they can't do: taste sweet things. According to a 2007 article in Scientific American, unlike other mammals, felines can't taste sweetness due to the fact that they "lack 247 base pairs of the amino acids that make up the DNA of the Tas1r2 gene. As a result, it does not code for the proper protein … and it does not permit cats to taste sweets." While that may sound a little complicated, you don't really need to understand the specifics to get that Fluffy won't enjoy sugary desserts.

If you find yourself only able to use the left side of your computer's keyboard, there are still plenty of words that you can type out. By using Q, W, E, R, T, A, S, D, F, G, Z, X, C, V, and B—the letters on the left side of the standard QWERTY keyboard—you can not only tap out whoppers like tesseradecades, aftercataracts, and sweaterdresses, you can also type great, vast, water, starter, cascades, retracts, affects, trees, caves, crests, waver, reverberate, sat, far, raced, faster, created, craters, graves, wasted, arrested, and (perhaps best of all) abracadabra. And if that's not a writing prompt, we don't know what is.

If you've ever broken a nail way down near the base—or lost one completely—you know they take quite a while to grow back. In fact, the American Academy of Dermatology says that a fingernail takes around six months to grow from base to tip and toenails can take up to a year. Fingernails also grow faster on your dominant hand as well as on your bigger fingers. Nails also grow faster during the daytime as well as during the summer months.

If you've ever said you'll "just be a jiffy," you probably know it's an expression used to indicate a short amount of time. However, according to Dictionary.com, a "jiffy" is an actual unit of time. Sometime during the late 18th or early 19th centuries, scientist Gilbert Newton Lewis defined a jiffy as the amount of time it takes light to travel one centimeter in a vacuum, which is about 33.4 picoseconds or one trillionth of a second. That's a short (and pretty much useless) amount of time indeed!

If you've recently picked up a Quarter Pounder or Chicken McNuggets, then you're among the nearly 70 million customers that McDonald's serves every day. However, it's not as easy for residents of Montpelier, Vermont, to get a Big Mac. That's because it's the only U.S. state capital that doesn't have a McDonald's. As the smallest state capital in terms of population (approximately 7,500), the city doesn't have a Burger King, either. Sorry, Whopper lovers! Luckily, to enjoy a meal from either fast-food chain, those from Montpelier can simply head over to the neighboring city of Barre.

When the public started using the phone back in the 1800s, inventor Alexander Graham Bell thought they should answer a call with "ahoy." That's likely why the incredibly elderly Mr. Burns on The Simpsons says "Ahoy-hoy" when he picks up the phone. However, Bell's rival, Thomas Edison, wanted users to answer the phone with "Hello." And, according to The New York Times, by 1880, "hello" had won out.

After multiple people claimed that they had passed kidney stones while riding Walt Disney World's Big Thunder Mountain Railroad ride, a research team from Michigan State University decided to take a look at the situation in 2016. When they conducted tests using a model kidney, they found that there was a 63.9 percent successful pass rate for those seated in the rear of the coaster. That number was just 16 percent for those seated in the front.

Unfortunately, this only worked on Big Thunder Mountain. "We tried Space Mountain and Aerosmith's Rock 'n' Roller Coaster and both failed," said one researcher. "The ideal coaster is rough and quick with some twists and turns, but no upside down or inverted movements."

Desserts don't have to be super complicated to be delicious. Take pound cake for example. Not only is it made from some pretty common ingredients—butter, eggs, sugar, and flour—according to What's Cooking America, its name comes from the fact that the original recipe called for a pound of each item. While that may seem like a lot, the simple recipe (which dates back to the 1700s) was easy to remember during a time when not everyone could read.

While your wallet may be filled with $5, $10, $20, $50, or even $100 bills, the government once decided that it might be handy to have some higher denominations available. That's why, at one point, there were banknotes of $500, $1,000, and even $5,000 value.

But the largest note ever issued for public circulation was the $10,000 bill, which featured a portrait of Salmon P. Chase, the Secretary of the Treasury from 1861 to 1864. The bills were first printed in 1945, and on July 14, 1969, the Federal Reserve and the Department of the Treasury announced that the larger bills would be discontinued due to lack of use. (Honestly, we can't image why.)

The human body is capable of amazing things. For instance, when your brain sends messages via your nerves, the signals travel along billions of nerve cells (neurons), synapses, and neurotransmitters in a process that can be as speedy as 200 miles an hour.

As they say, an apple a day keeps the doctor away. Unless you eat too many apple seeds, that is. The tiny black seeds found in the fruit contain a plant compound called amygdalin which turns into hydrogen cyanide if the seeds are chewed or digested, according to Medical News Today. Cyanide is poisonous (even deadly in high doses), which is why you should definitely spit those seeds out. Do the same for apricot, peach, and cherry seeds, which also contain the compound as well.

Mulan is fierce, brave, and incredibly inspirational. But she's also incredibly deadly. In fact, she was not only the first Disney princess to kill someone on-screen in the 1998 film Mulan, but she also has the highest kill-count of any Disney character, according to UNILAD. Mulan took out 1,995 people over the course of the film, including the evil Hun leader, Shan-Yu, and 1,994 Huns by triggering an avalanche.

There will always be fierce debates over whether or not pineapple has any place on a pizza, but there's no question about where the Hawaiian pizza originally came from: Chatham, Ontario, Canada! Restaurant owner Sam Panopoulos was born in Greece but moved to Canada when he was 20 years old. And in 1962, the entrepreneur decided to put pineapple on pizza.

According to Time, Panopoulos, who passed away in 2017, once told the BBC, "We just put it on, just for the fun of it, see how it was going to taste. We were young in the business and we were doing a lot of experiments." The name apparently came from the brand of canned pineapple that was used when they invented the Hawaiian pizza.

Dr. Seuss is responsible for coming up with some wild and wacky words. But we can also thank the children's book author for a very common term: nerd. American Heritage Dictionary explains that "nerd" first appeared in Seuss' 1950 book If I Ran the Zoo. The passage reads, "And then, just to show them, I'll sail to Ka-Troo and bring back an It-Kutch, a Preep, and a Proo. A Nerkle, a Nerd, and a Seersucker, too!"

According to Merriam-Webster, a year later, Newsweek included the word "nerd" in an article about the latest slang, writing, "In Detroit, someone who once would be called a drip or a square is now, regrettably, a nerd, or in less severe cases, a scurve." Too bad "scurve" didn't catch on.

Human bodies can sometimes feel vulnerable and fragile. But if you want to feel like a superhero, keep in mind that human bone is actually stronger than both steel and concrete. "Bone is extraordinarily strong—ounce for ounce, bone is stronger than steel, since a bar of steel of comparable size would weigh four or five times as much," biomedical engineer Cindy Bir at Wayne State University told Live Science in 2010. "A cubic inch of bone can in principle bear a load of 19,000 lbs. (8,626 kg) or more—roughly the weight of five standard pickup trucks—making it about four times as strong as concrete."

Birds can do some pretty amazing things. For example, frigate birds (Fregata minor) can sleep while flying. That's because they can snooze while using only one hemisphere of the brain at a time, according to the National Audobon Society.

According to a 2012 study published in the journal Annals of Epidemiology, humans are 13.8 percent more likely to pass away on their birthday than on any other day. That's according to Swiss mortality statistics from 1969 to 2008. We've got to say, this study is (morbidly) interesting!

Playing electronic dance music (EDM) may scare people away, and it turns out, it could do the same with mosquitos. According to one 2019 study, the Skrillex song "Scary Monsters and Nice Sprites" combines "very high and very low frequencies" as well as "excessive loudness and constantly escalating pitch" that discourages the yellow fever mosquito from biting victims and mating.

The nine-letter "spoonfeed" is the longest word that's spelled with letters that are arranged completely in reverse alphabetical order. "Trollied" comes in second place with eight letters.

If you're trying to locate Rome on a map, you'd probably head right to the boot-shaped country of Italy. But Europe isn't the only place that decided to use that particular name, or rather, the Italian version, "Roma." In fact, there's a Rome on every continent except Antarctica.

Nobel Prize-winning scientist Marie Curie died as a result of the vast amounts of radiation she was exposed to during her groundbreaking work. But her body wasn't the only thing to absorb the emissions. Her clothes and belongings—including her furniture, cookbooks, and laboratory notes—were also saturated with the deadly radium particles. That's why, even though Curie died around 85 years ago, her possessions are still radioactive.

And since radium has a half-life of 1,601 years, they're likely to stay that way for a while. Currently, Curie's laboratory notebooks are being safely stored in lead-lined boxes at France's Bibliotheque National in Paris. Anyone who wants to see them has to first to sign a liability waiver and then agree to wear protective gear.