Original photo by Chris Willson/ Alamy Stock Photo
In 1998, a fur-covered robot hit store shelves just in time for the holiday shopping season, creating a frenzy among parents. Manufacturer Tiger Electronics had released the first real-life robotic pet: Furby. Partially resembling a hamster (thanks to its scruffy acrylic fur) and an owl (complete with pointed ears and a beak), the computerized toy greeted children and sang to them in Furbish, an entirely made-up language. Furby’s main hook was all about interaction; it could be startled by loud noises, responded to petting, and danced when it was happy, just like a real animal might. But the most innovative feature was that the small robots could supposedly learn English, a gimmick that created a whirlwind of conspiracies, including the idea that Furby was an international spy.
Furby was the first robotic toy to use artificial intelligence.
A slew of robotic toys emerged around 2000, heralding the millennium with computerized novelties. But Furby was considered the first of its kind to use (rudimentary) artificial intelligence, equipped with sensors that allowed it to respond to humans and other Furbys.
Because Furby was the first toy of its kind, most people didn’t understand how it “learned” language, and the initial fervor was so intense that it led the National Security Agency to ban the toys from its premises; it was also banned from the Norfolk Naval Shipyard and the Pentagon. NSA agents believed the robots were embedded with recording devices that could allow them to listen in on sensitive topics and later replay classified conversations. Tiger Electronics refuted the ban, explaining that while the toy was unique, “Furby [was] not a spy,” going so far as to reveal that the toys were preprogrammed with around 200 words — meaning they didn’t actually learn anything — and that they slowly unveiled their vocabulary the longer a child played. Meanwhile, the outlandish Furby fears (including the belief that it could launch a space shuttle) didn’t slow its popularity; more than 40 million of the revolutionary robots were sold in the first three years.
Today, personal electronics sometimes seem like the only way to cope with the grueling ordeal of air travel, helping us pass the time with an in-flight movie or music. But that wasn’t always the case — not so long ago, the Federal Aviation Administration (FAA) prohibited using CD players, laptops, and even Furbys on airplanes. The 1990s ushered in a wave of portable electronics, and with their popularity came a theory that many devices could interfere with a plane’s navigation system, creating chaos in the skies. In an effort to protect passengers and pilots, the FAA banned the use of many electronics during takeoff and landing, including the incredibly popular robotic toy, which had to have its batteries removed before takeoff. No plane control issues were ever attributed to a Furby on board, though there likely was one benefit to powering down the robots while in air: their silence, since many people found their constant chatter grating.
Nicole Garner Meeker
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Nicole Garner Meeker is a writer and editor based in St. Louis. Her history, nature, and food stories have also appeared at Mental Floss and Better Report.
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The very first pencils arrived around the dawn of the 17th century, after graphite (the real name for the mineral that forms a pencil’s “lead”) was discovered in England's Lake District. But the eraser didn’t show up until the 1770s, at the tail end of the Enlightenment. So what filled the roughly 170-year-long gap? Look no further than the bread on your table. Back in the day, artists, scientists, government officials, and anyone else prone to making mistakes would wad up a small piece of bread and moisten it ever so slightly. The resulting ball of dough erased pencil marks on paper almost as well as those pink creations found on the end of No. 2 pencils today.
The writer and philosopher Henry David Thoreau invented a popular American pencil.
Known best for literary works such as “Walden,” Henry David Thoreau and his family owned a pencil company where Thoreau mixed clay with graphite to make a variety of pencils, including the first No. 2.
But in 1770, English chemist Joseph Priestly (best known for discovering oxygen) wrote about “a substance excellently adapted to the purpose of wiping from paper the marks of a black lead pencil.” This substance, then known as caoutchouc, was so perfect for “rubbing” out pencil marks that it soon became known simply as “rubber.” Even today, people in the U.K. still refer to erasers as “rubbers.” (The name “lead-eater” never quite caught on.)
The Japanese electronics company Sharp is named after the world’s first mechanical pencil.
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Yellow pencils were first marketed as a luxury item.
When someone says “pencil,” a slender, yellow stylus topped with a pink eraser likely comes to mind — evidence that a 120-year-old ad campaign is still hard at work. In 1899, hoping to differentiate its pencils from the rest, a Czech manufacturing company named Hardtmuth Pencil decided to paint its “luxury pencil” yellow. At the time, painted pencils were usually red, purple, or black, since darker colors covered up imperfections. Yet Hardtmuth wanted to advertise its top-of-the-line graphite sourced from Siberia. The company went with yellow because of the color’s long association with royalty in China (Siberia’s next-door neighbor). Soon, other companies followed suit, and the yellow pencil became ubiquitous around the world.
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Darren Orf lives in Portland, has a cat, and writes about all things science and climate. You can find his previous work at Popular Mechanics, Inverse, Gizmodo, and Paste, among others.
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When it comes to the Amazon River, there’s no such thing as water under the bridge. The idiom simply doesn’t apply there, as no bridges cross the Amazon River, despite it being at least 4,000 miles long. This isn’t because the idea has never occurred to anyone — it would just be extremely difficult to build any. The Amazon has both a dry season and a rainy season, and during the latter its waters rise 30 feet, causing 3-mile-wide crossings to grow by a factor of 10 as previously dry areas are submerged. The river bank itself is also in a near-constant state of erosion due to how soft the sediment it consists of is, and there’s no shortage of debris floating in the water.
The longest river in the world is actually the Nile, which is 4,132 miles long — about 132 miles longer than the Amazon, though counts vary. Third on the list is the Yangtze, at 3,915 miles.
Beyond all those logistical hurdles, there simply isn’t much use for bridges across the massive river. For one thing, there are few roads on either side of the Amazon that need to be connected. The river is, of course, in the middle of a dense rainforest, the vast majority of which is sparsely populated. Other long rivers have numerous crossings, however: The Nile has nine bridges in Cairo alone, for instance, and more than 100 bridges have been built across China’s Yangtze River in the last three decades. For now, boats and ferries are the preferred method of crossing the Amazon, and are likely to remain so for the foreseeable future.
The Amazon used to flow in the opposite direction.
These days, the river flows east and into the Atlantic. That wasn’t always the case, as it used to flow west into the Pacific — and even both directions simultaneously. This was during the Cretaceous Period, between65 million and 145 million years ago, and was the result of a highland (mountainous area) that formed along the east coast of South America when that landmass and Africa broke apart. The Andes eventually formed on the western half of the continent, which forced the river into its current eastward flow.
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Michael Nordine is a writer and editor living in Denver. A native Angeleno, he has two cats and wishes he had more.
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Stage names are hardly uncommon in Hollywood, but false initials are rarer — if not unheard of. To wit: Michael J. Fox’s middle name doesn’t start with “J.” The Back to the Future star’s middle name is actually Andrew, but there already was a Michael A. Fox in the Screen Actors Guild when Fox wanted to join it. So why the “J”? The letter is an homage to Michael J. Pollard, a character actor Fox admires. Pollard had more than 100 acting credits to his name by the time he died in 2019, and received Academy Award, BAFTA, and Golden Globe nominations for his role as gas station attendant-turned-accomplice C.W. Moss in 1967’s Bonnie and Clyde.
Fox wasn’t originally cast in “Back to the Future.”
John Cusack, Charlie Sheen, Ralph Macchio, and many others all auditioned for the role of Marty McFly, but Eric Stoltz was cast. It wasn’t until six weeks into production that director Robert Zemeckis let Stoltz go, feeling he wasn’t right for the part, and Fox got the role instead.
Some other stage names are so successful that most people don’t realize they’re stage names. Sir Elton John was born Reginald Kenneth Dwight, for instance, while Jamie Foxx’s real name is Eric Marlon Bishop, and Whoopi Goldberg’s is Caryn Elaine Johnson — to name just a few.
Fox, for his part, was diagnosed with Parkinson’s disease in 1991, announced his condition in 1998, and retired from acting in 2020. He founded the Michael J. Fox Foundation for Parkinson’s Research in 2000 and remains devoted to finding a cure for the disease.
“Back to the Future” was almost named “Spaceman From Pluto.”
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Middle names date back to ancient Rome.
Well, kind of. Many Romans had three names, but their second name wasn’t quite a middle name. There was the praenomen (personal name), nomen (family name), and cognomen, which indicated which branch of a family you were from. (For instance, Julius Caesar’s full name was actually Gaius Julius Caesar.) There was also a hierarchical element to the Roman naming system, as women generally had only two names and enslaved people often had only one. Middle names as we know them today arose in the Middle Ages, a time when faithful Europeans struggled between giving their children a family name or that of a saint. Eventually deciding that both would be preferable to one, they began the tradition of a child receiving a given name, baptismal name (saint’s name), and surname. That custom eventually reached America along with the people who emigrated there, with secular middle names becoming more common over time.
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Michael Nordine is a writer and editor living in Denver. A native Angeleno, he has two cats and wishes he had more.
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There are a few ways to avoid the itch-inducing bites of summer’s biggest pest: the mosquito. Wearing long-sleeved apparel and dousing yourself in insect repellent can help, but avoiding some beverages — particularly alcohol — might further protect you. According to a 2010 study of mosquito biting preferences, beer makes humans more attractive to the paltry pests.
Researchers found that Anopheles gambiae, a mosquito species in the genus responsible for transmitting malaria, were more attracted to humans who had consumed beer (compared to those who consumed only water), and the results were evident as soon as 15 minutes after the humans began drinking. Other studies have produced similar findings; one examination of alcohol’s role in mosquito meal choices found that those who imbibed just one 12-ounce beer were more likely to be pestered by the insects. It’s unclear why beer primes humans to become bite victims, though some scientists believe it could be partly linked to body temperature; alcohol expands the blood vessels, a process that slightly increases the skin temperature and also makes us sweat, two factors that may attract more hungry mosquitoes.
Not every mosquito you see is out for blood. That’s because only female mosquitoes bite, in search of blood that provides them with enough protein to develop eggs and successfully reproduce, while males feed on nectar.
For being such tiny insects, mosquitoes are incredibly effective in their ability to feast on larger prey. Their proboscises — aka mouths — are created from a complex system that includes six needlelike mouthparts called stylets; when a mosquito bites, the stylets are used to hunt for nearby blood vessels. That makes a mosquito’s job of finding food quick and easy work — a necessity when dinner comes with a risk of being swatted.
London’s subway system has a type of mosquito named after it.
There are thousands of mosquito breeds throughout the world, but London has one subspecies informally named for its subway system. Scientists believe the Culex pipiens molestus, often called the London Underground mosquito, is a variation of the Culex pipiens, the most widespread mosquito in the world. The London Underground mosquito is thought to have lived beneath the city’s streets for around 150 years. While the pests were acknowledged during World War II, when Brits sheltering below ground were bitten by the hungry insects, it wasn’t until decades later that researchers began to study them in earnest. By 1999, English researcher Katharine Byrne determined that the mosquitoes living in London’s subway tunnels had morphed into their own subspecies, unable to even breed with other species. However, more recent research suggests the pests evolved not inside the Underground, but possibly in Egypt and nearby areas centuries ago. Today, Culex pipiens molestus is found in underground locations in many parts of the world.
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Nicole Garner Meeker is a writer and editor based in St. Louis. Her history, nature, and food stories have also appeared at Mental Floss and Better Report.
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Most people logically assume the maximum time difference between any two places on Earth would be 24 hours. After all, that’s how long it takes our planet to spin once, so it seems sensible that no two points on Earth could be more than one full rotation apart. Systems crafted by humans, however, are often anything but sensible — and the actual maximum time difference on Earth is 26 hours. So where do those extra two hours come from?
The conventional time zone system runs from UTC-12 in the west to UTC+12 in the east (UTC meaning “Coordinated Universal Time”), which would produce a maximum gap of 24 hours. Within that system there are 38 offsets, which is the amount of time a specific region’s local clock is ahead of or behind UTC. UTC-12, for example, refers to a time zone that’s 12 hours behind UTC, while UTC+12 would be 12 hours ahead.
Those offsets normally remain within the 24-hour frame, but there are places on Earth that have gone against that convention, winding up in UTC+13 and UTC+14. Three places are responsible for this strange occurrence: Howland Island, Baker Island, and the Line Islands of Kiribati.
About 600 million years ago, a day on Earth lasted just 21 hours.
Due to tidal friction caused by the gravitational pull of the moon, Earth’s rotation has been gradually slowing down throughout most of the planet’s history. Because of this, the length of a day has increased by about 1.8 milliseconds per century on average.
Howland Island and Baker Island are uninhabited coral atolls (and unincorporated U.S. territories) sitting at UTC-12, at what is considered the extreme west of our planet. Kiribati, meanwhile, sits in the extreme east — and is home to the strange time zone of UTC+14.
Despite being more than an entire day apart on the calendar, those islands are only a few hundred miles away from each other in the Pacific Ocean, thanks to the spherical nature of the planet and the way we draw our lines of longitude. So, while it’s 10:30 p.m. on a Wednesday on Howland Island and Baker Island, it can be 12:30 a.m. on a Friday in the Line Islands.
While this may seem odd, there’s a logical reason why Kiribati ended up at UTC+14. The islands were once located right on the international date line, meaning a full 24-hour gap existed within the same territory, so while it was Monday in the western islands, it was Sunday in the east.
To eliminate that confusion, Kiribati made the decision to essentially move the international date line at the very end of 1994, placing all its territories on the same date. The result was UTC+14, a time zone that shouldn’t technically exist, and a 26-hour gap between Kiribati and its Pacific neighbors.
The largest country with only one time zone is China.
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A day on Venus is longer than a year on Venus.
Venus is arguably the strangest planet in our solar system when it comes to time. A year — the time it takes to orbit the sun once — is 225 Earth days on Venus, which sounds fairly normal until you learn that a single day on the planet (one full rotation on its axis) takes 243 Earth days. Therefore, a day on Venus is technically longer than its year.
To make things even more bizarre, Venus rotates backward compared to most planets, including Earth, in what is known as a retrograde rotation. Earth spins counterclockwise, but Venus spins clockwise, so on Venus, the sun rises in the west and sets in the east.
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Tony is an English writer of nonfiction and fiction living on the edge of the Amazon jungle.
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In the majority of countries, including the United States and United Kingdom, “adulthood” is often said to begin at 18, when people gain certain rights and privileges such as the ability to vote or enter legally binding contracts. But neuroscientifically speaking, the true age of adulthood is one that most people let pass by without any fanfare.
In 2025, scientists at the University of Cambridge published a study in which they determined the brain goes through five stages of aging — and, on average, the “adult” stage begins around age 32. According to the research, which studied the brains of nearly 4,000 people between the ages of 0 and 90, the human brain has four “turning points” over a lifetime, which correspond to major changes in its neural wiring. Those changes happen around ages 9, 32, 66, and 83, and divide the lifespan into five brain eras: childhood, adolescence, adulthood, early aging, and late aging.
In the first three years of life, human brains form more than a million neural connections per second.
Babies continuously take in a huge amount of information while learning about themselves and their environment. After the rapid expansion of the first few years, the brain goes through a pruning process in which some connections are strengthened and others are weakened.
Adulthood is by far the longest of the identified eras, lasting roughly three decades. During that time, the brain is much more stable than in previous eras, without any major changes in its size or physical wiring. There’s also a plateau in intelligence and personality, which don’t go through the transformations often seen in younger people “discovering” themselves and making new neural associations with the world around them.
The legal voting age in the U.S. was 21 until 1971.
Throughout most of U.S. history, the legal voting age was 21. This was established by the American colonies, which adopted the practice from England. It wasn’t until World War II that people began seriously campaigning for a reconsideration of the age limit, due in large part to the fact that soldiers were admitted to (or drafted into) the Army at a minimum age of 18.
From the 1940s until the 1970s, several states considered a change in minimum voting age, but only a few actually made the switch. The slogan “old enough to fight, old enough to vote” regained momentum during the Korean War and Vietnam War. Although there was much debate in Congress about the implications of allowing teenagers to vote, the resolution was finally passed in 1971 and the 26th Amendment granted voting rights to citizens 18 and older. The amendment had the shortest ratification period of any in U.S. history.
Ali Eldridge
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Ali Eldridge is a writer and editor based in Chicago. Currently the editor of "What on Earth! Magazine," she has also contributed extensively to Encyclopaedia Britannica and published several books for children. She spends much of her free time learning new languages and trading puns with her clever kid.
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Deciding when to observe holidays isn’t always an exact science. George Washington wasn’t born on the third Monday of February, for example. Memorial Day’s precise date on the calendar shifts from year to year (it’s always the final Monday of May, in case you’d forgotten), but at least the reasoning behind it is sound: The late spring date was chosen because it was when flowers would be in full bloom. Since adorning the graves of fallen soldiers with wreaths was once the most important part of the holiday, it’s difficult to imagine Memorial Day taking place at another time of year — especially considering that it was first celebrated in the 1860s, when floristry wasn’t quite as commercially developed as it is today.
It was originally known as Decoration Day, due to the fact that graves were decorated with flowers. By the late 19th century, as the holiday became more widespread, the name Memorial Day gradually replaced the original moniker.
Certain aspects of the holiday’s origins are murky, but we know that in the wake of the Civil War, many different communities around the country decorated the graves of dead soldiers with blossoms and said prayers. In 1868, General John A. Logan, who led an organization for Northern Civil War veterans, chose May 30 “for the purpose of strewing with flowers, or otherwise decorating the graves of comrades who died in defense of their country during the late rebellion, and whose bodies now lie in almost every city, village and hamlet churchyard in the land.” Originally set aside specifically for the Civil War, Memorial Day came to encompass all military casualties during World War I. And while initially it was celebrated on a state and community-wide basis, it became an official federal holiday in 1971.
More than 20 towns claim to be Memorial Day’s birthplace.
Only one of them is recognized as such, however: Waterloo, New York. President Lyndon B. Johnson made it official with a 1966 proclamation that also recognized the centennial of its first observation of Memorial Day, which took place in the town on May 5, 1866. According to Richard Gardiner, co-author of The Genesis of the Memorial Day Holiday in America, however, no such celebration took place in 1866, and Waterloo’s claim to the title is dubious — not that it’s at risk of being taken away. Other towns with their own claims of being the holiday’s birthplace include Boalsburg, Pennsylvania; Carbondale, Illinois; and both Columbus, Mississippi, and Columbus, Georgia, among many others.
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Michael Nordine is a writer and editor living in Denver. A native Angeleno, he has two cats and wishes he had more.
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The animal kingdom is full of incredible variety, thanks to evolution, but one thing most animals have in common is that they use a set of eyes to navigate the world around them. But even the pupil of the eyeball, the biological aperture responsible for how much light enters the eyes, is nearly as diverse as the types of birds that soar the skies or fish that swim the seas.
Humans can’t keep their eyes open when they sneeze.
Most people experience an automatic response to close their eyes when sneezing, but it is possible to keep them open (your eyes won’t pop out either). Scientists think the response keeps irritants, which the sneeze just expelled, from reentering the body through the eyes.
For mammals, one big factor determining the shape of a pupil is whether the creature is predator or prey. For example, a goat is a grazing prey animal that would be a pretty easy target for coyotes, bears, and other predators with sharp teeth. Yet evolution gave the goat a few tools to defend itself. The horns certainly help, but the biggest advantage is a goat’s horizontal rectangular pupils. These long, horizontal pupils create a panoramic view that lets the animal see more of the landscape, which makes it harder to sneak up on them. The pupils also enhance the image quality of objects (read: threats) all around the goats, and they cut down on glare from the sky by capturing less light from above and more from below. Cats and snakes, on the other hand, are ambush predators, whose vertical pupils help them hunt in the night and judge the distance between themselves and their next meal. But according to scientists, vertical pupils are reserved only for animals whose eyes are close to the ground. That’s why other cats that are higher up, like lions and tigers, have round pupils rather than vertical ones.
The first use of the acronym GOAT (Greatest Of All Time) was in reference to Muhammad Ali.
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Goats have accents.
A 2012 study from Queen Mary University of London revealed that kids (the goat kind, not the human kind) altered their bleating when socializing with other goats. The ability to change one’s voice in response to a social environment is known as “vocal plasticity,” and humans display an extreme form of this concept — it’s how we can develop accents. Goats develop similarly distinct accents based on their social group, admittedly with a more limited vocabulary. In the study, scientists analyzed 1-week-old goats compared to 5-week-old goats; the latter is about the time goats form social groups known as “crèches.” They found that young goats raised in the same crèchesdeveloped similar bleats, altering their noises to fit in their social group as they aged. It’s also possible these accents help goatsidentify members of their group, an idea familiar to anybody who’s traveled outside their home country — oreven their hometown.
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Darren Orf lives in Portland, has a cat, and writes about all things science and climate. You can find his previous work at Popular Mechanics, Inverse, Gizmodo, and Paste, among others.
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At 3:45 p.m. on September 9, 1947, a computer programmer working on the Mark II at Harvard recorded in a logbook that the team had discovered the “first actual case of [a] bug being found.” But the programmer wasn’t referring to some poorly written lines of code — this was an actual bug. A moth, to be exact, which had flown into a room where the Mark II, one of the world’s first computers, was housed at the university. Attracted by the warmth of the 25-ton machine, the winged creature met its end in one of the many electromagnetic relay contacts. The team removed the moth with tweezers.
Nikola Tesla was the first to coin the engineering term “bug.”
American inventor Thomas Edison made several references to “bugs” in his notebooks in the mid-1870s, defining them as “bug — as such little faults and difficulties are called.” By 1889, newspapers reported on how Edison was hard at work fixing a “bug” in his phonograph.
While this event is often mistakenly cited as the birth of the programming term “bug” to mean a flaw or imperfection, the word had actually been used in engineering circles for over half a century. But the 1947 moth misadventure was popularized by Grace Hopper, a mathematician and computer science pioneer who worked with the team as they “debugged” the Mark II. Early computers such as Harvard’s Mark series were responsible for other modern computer programming lingo, though: For example, a “patch” comes from the punched cards used in early machines that programmers physically “patched” with tape to fix errors. Today, the original Mark II logbook — with the original “bug” taped to it — is at the Smithsonian Museum of American History.
The word “bug” likely first appeared in an early English translation of the Bible.
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“Spam” took on the additional meaning of junk email thanks to a sketch by the British comedy troupe Monty Python.
The sketch begins with a simple request: A couple in a diner wants to order food. Unfortunately, the proprietor of the establishment serves a very Spam-heavy menu, including “Spam Spam Spam Spam Spam Spam Spam baked beans Spam Spam Spam and Spam.” Originally airing on Monty Python’s Flying Circus in 1970, the sketch later became associated with annoying floods of data, ads, or massive amounts of useless text. The word likely first appeared online in late 1980s MUDs (multi-user dungeons), where users could “spam the database” by using a program to create lots of objects in the shared digital space, among other pesky, repetitive behaviors. By 1990, archived MUD chats show that the use of the term “spam,” along with its sketch comedy origins, had been officially established.
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Darren Orf lives in Portland, has a cat, and writes about all things science and climate. You can find his previous work at Popular Mechanics, Inverse, Gizmodo, and Paste, among others.
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