In some parts of the world, it's easier to get an automatic rifle than a glass of clean drinking water. Is this just the way it is? Samantha Nutt, doctor and founder of the international humanitarian organization War Child, explores the...

Experimental psychologist Petter Johansson researches choice blindness -- a phenomenon where we convince ourselves that we're getting what we want, even when we're not. In an eye-opening talk, he shares experiments (designed in...

The suits, numbers and colors in a deck of cards correspond to the seasons, moon cycles and calendar. Marco Tempest straps on augmented reality goggles and does a card trick like you've never seen before, weaving a lyrical tale as he...

Moser's circle problem, and its solution.

A quick explanation of e^(pi i) in terms of motion and differential equations

You're overseeing the delivery of supplies to a rebel base in the heart of enemy territory. To get past customs, all packages must follow this rule: if a box is marked with an even number on the bottom, it must be sealed with a red top....

The fact that no one knows the answer to this question is what makes it exciting. The story of physics has been one of an ever-expanding understanding of the sheer scale of reality, to the point where physicists are now postulating that...

Atoms can (and do) bond constantly; it's how they form molecules. Sometimes, in an atomic tug-of-war, one atom pulls electrons from another, forming an ionic bond. Atoms can also play nicely and share electrons in a covalent bond. From...

There is a proof for Brouwer's Fixed Point Theorem that uses a bridge - or portal - between geometry and algebra.

Quantum mechanics is perhaps the most unintuitive theory ever devised. And yet it's also the most successful, in terms of sheer predictive power. Simply by following the math of quantum mechanics, incredible discoveries have been made....

It sounds counterintuitive, but by 2030, many of the world's largest economies will have more jobs than adult citizens to do those jobs. In this data-filled -- and quite charming -- talk, human resources expert Rainer Strack suggests...

As we react to the predictions that epidemiological models make, changing the ways we act and go about our lives, those estimates can appear totally off. But if a model’s predictions end up being wrong, that might mean it's done exactly...

The One That Got Away (Size Matters)

Think we're winning the battle against HIV? Maybe not, as the next wave of drug-resistant viruses arrives. In an eye-opening talk, TED Fellow Edsel Salvana describes the aggressive HIV subtype AE that's currently plaguing his home of the...

An overview of what a neural network is, introduced in the context of recognizing hand-written digits.

Happy pi day! Did you know that in some of his notes, Euler used the symbol pi to represent 6.28..., before the more familiar 3.14... took off as a standard?

In a lively show, mathemagician Arthur Benjamin races a team of calculators to figure out 3-digit squares, solves another massive mental equation and guesses a few birthdays. How does he do it? He’ll tell you.

HIV is a serious problem in the DR Congo, and aid agencies have flooded the country with free and cheap condoms. But few people are using them. Why? "Reformed marketer" Amy Lockwood offers a surprising answer that upends a traditional...

The human brain is puzzling -- it is curiously large given the size of our bodies, uses a tremendous amount of energy for its weight and has a bizarrely dense cerebral cortex. But: why? Neuroscientist Suzana Herculano-Houzel puts on her...

The city has just opened its one-of-a-kind Faberge Egg Museum, with a single egg displayed on each floor of a 100-story building -- and the world's most notorious jewel thief already has her eyes on the prize. Can you help the thief...

Artist Safwat Saleem grew up with a stutter -- but as an independent animator, he decided to do his own voiceovers to give life to his characters. When YouTube commenters started mocking his Pakistani accent, it crushed him, and his...

One bag of apples, one apple, one slice of apple -- which of these is one unit? Explore the basic unit of math (explained by a trip to the grocery store!) and discover the many meanings of one.

Bad news: your worst enemies are at the gate. Your fledgling kingdom guards the world's only herd of tiny dino creatures. To you, they're sacred. To everyone else, they're food. The three closest nation-states have teamed up to smash...

You and nine other individuals have been captured by super-intelligent alien overlords. The aliens think humans look quite tasty, but their civilization forbids eating highly logical and cooperative beings. Unfortunately, they're not...