What's New
The latest primers to land on NeedsNoIntro, newest first. New subjects arrive in batches, so each group below is one publish day.
October 24, 2026
30 new subjects
The Internet & Web
Wi-Fi
Invisible radio waves, a pun on hi-fi, and the reason your living room has a worse signal than your kitchen.
Nutrition Science
Vitamins
Tiny molecules with enormous résumés: you need them in minuscule amounts, and you cannot do without them.
Ancient Civilizations
The Sumerians
They invented a way to press ideas into clay, and in doing so gave history its first draft.
American History
The Great Depression
A stock market crash was only the opening act of a decade in which a quarter of American workers had no job to go to.
Evolution & Origins
The Extinction of the Dinosaurs
One bad rock, one very bad day, and the Age of Dinosaurs got an abrupt ending, with a few feathery survivors.
Medieval & Renaissance Europe
The Black Death
The worst pandemic in European history arrived by ship, stayed for four years, and rearranged the continent's economy on its way out.
Individual & Racket Sports
Surfing
The sport of standing on a moving piece of the ocean, which once nearly vanished and now has Olympic medals.
Diseases & Conditions
Stroke
A brain attack: no warning bell, no waiting room, and a clock that starts the moment symptoms do.
Instruments & Music Theory
Saxophone
A brass-colored instrument that is secretly a woodwind, invented by a man who spent a decade in court defending it.
Sleep Science
REM Sleep and Dreams
Your brain runs a nightly film festival while your body politely stays in its seat.
Mathematics
Probability
Probability is the math of things you cannot be sure about, which is nearly everything, including whether you will need an umbrella.
Animal Kingdom
Octopuses and Cephalopods
Eight arms, three hearts, blue blood, and a skin that doubles as a mood ring and a disguise kit.
Evolution & Origins
Neanderthals
Our stocky, toolmaking cousins who ran the cold half of the Ice Age and still show up in your DNA.
Biology
Mitochondria
Tiny former bacteria living inside nearly every cell you own, quietly paying the electric bill.
Women's Health
Menopause
A natural biological milestone that arrives with a long runway and surprisingly little advance briefing.
History of Science & Medicine
Marie Curie
She won two Nobel Prizes in two different sciences, drove X-ray machines to the front lines, and did it all in an era that barely let women into the lab.
Space
How Stars Live and Die
Stars are born in cold clouds, burn on gravity-powered fusion, and go out with either a whimper or the biggest bang in the galaxy.
Physics
Gravity
The force that keeps you in your chair, the Moon in the sky, and physicists awake at night.
Artificial Intelligence
Generative AI
A very well-read autocomplete that learned to write essays, paint pictures, and occasionally make things up with a straight face.
Beverages
Espresso
A tiny, intense coffee made by forcing hot water through a puck of grounds in about half a minute, and the base of nearly every cafe menu.
Biology
Epigenetics
Same script, different performances: how the cells in your body read the same DNA and end up as brain, skin, or liver.
Neuroscience
Dopamine
The most misunderstood molecule in your skull: less "feel-good chemical," more "this seems worth doing."
Diseases & Conditions
Diabetes
Your body's fuel system works great until the key that lets sugar into your cells goes missing or stops fitting the lock.
Ecology
Coral Reefs
Cities built by animals the size of a pencil eraser, now living on the edge of a thermometer.
First Aid & Safety
Concussions
Your skull is a great helmet, right up until the brain inside takes a ride of its own.
Medicine & Treatments
Cholesterol
A waxy substance your body needs and your arteries would rather you not overdo.
Famous Landmarks
Angkor Wat
A 12th-century temple so grand that it ended up on a national flag, and so well made it outlasted the empire that built it.
Diseases & Conditions
Alzheimer's Disease
It starts as a misplaced set of keys and can grow into the slow loss of the story a person tells about their own life.
History of Science & Medicine
Alexander Fleming and Penicillin
A messy lab, a summer vacation and a stray mold spore gave medicine its first mass-produced antibiotic, though it took other people to make it work.
Mental Health
ADHD
A brain with a world-class browser history and no idea why it walked into this room.
October 17, 2026
30 new subjects
World Religions
Zoroastrianism
One of the world's oldest living faiths turns daily life into a choice between truth and the lie, with a sacred fire watching.
Medieval & Renaissance Europe
The Vikings
They sailed to Newfoundland nearly five centuries before Columbus, and still the internet insists on putting horns on their helmets.
American History
The US Constitution
A few thousand words, drafted in a hot Philadelphia summer, that still decide who gets to run the country and how.
Famous Landmarks
The Taj Mahal
History's most famous love letter was written in marble and took more than twenty years to finish.
The Human Body
The Skeletal System
Your scaffolding is alive: it banks calcium, brews blood, and quietly rebuilds itself while you sit there.
Medieval & Renaissance Europe
The Middle Ages
A thousand years of European history that gets remembered as knights, castles, and plague, and was a lot more than that.
Women's Health
The Menstrual Cycle
Your body runs a monthly rehearsal for pregnancy, and when the show does not go on, it cleans up the stage.
Fitness & Exercise
Stretching and Flexibility
Touching your toes is optional; understanding what stretching can and cannot do for you is not.
Mathematics
Prime Numbers
The loneliest numbers in math turn out to be the ones holding up everything else.
Personal Finance
Mortgages
A mortgage is how ordinary people buy something worth many years of salary: by promising to pay for it slowly, with interest.
World Cuisines
Mexican Cuisine
Tacos are just the doorway: behind them stands a food system thousands of years in the making that UNESCO treats as living heritage.
Animal Kingdom
Mammals
If you have fur, milk, or a cat, you are in the club, and so is a blue whale.
Nutrition Science
Macronutrients
Everything you eat boils down to three big players, and your food label has been quietly keeping score.
Evolution & Origins
Human Evolution
Your family tree turns out to be less a tree than a very crowded, very bushy shrub.
Sleep Science
How Sleep Works
Every night you voluntarily go unconscious for hours, and science is still arguing about exactly why.
Botany & Plants
How Plants Grow
Plants never stop growing, which is why a seed the size of a lentil can eventually become a redwood.
Neuroscience
How Neurons Work
Your thoughts are a very large number of tiny cells passing electrical sparks and chemical notes to one another.
History of Science & Medicine
Hippocrates
The most famous doctor in history may be as much a symbol as a person, and the oath with his name on it probably is not his.
Ecology
Food Webs
Nobody in nature eats just one thing, which makes the dinner table of an ecosystem look a lot more like a tangled web than a tidy line.
Friendship
Emotional Intelligence
Reading a room is a real skill, but the hype that it beats IQ was always a bit of a stretch.
Biology
DNA and RNA
DNA is the master recipe book; RNA is the photocopy that actually makes it to the kitchen.
How Government Works
Democracy
Rule by the people sounds simple until you ask which people, and who counts the votes.
First Aid & Safety
CPR
Two hands, a steady rhythm, and a phone call can buy a stranger crucial time, and it is a skill you hope never to use.
Artificial Intelligence
Computer Vision
Teaching a computer to see turned out to be much harder than teaching it to play chess, and much more useful.
Investing
Compound Interest
Compound interest is what happens when your money gets a job and then hires its own employees.
Diseases & Conditions
Cancer
Your cells follow strict rules about when to divide and when to die; cancer is what happens when some of them stop listening.
Music Genres
Blues
Three chords, twelve bars, and a bad day: the recipe that ended up underneath almost everything you hear on the radio.
Medicine & Treatments
Blood Pressure
Two numbers, one cuff, and the quietest early-warning system your body has.
Mental Health
Bipolar Disorder
It is a medical condition, not a personality quirk: mood and energy shift far beyond the ordinary ups and downs.
Chemistry Basics
Atoms
Everything you have ever touched is mostly empty space wearing a very convincing disguise.
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