An animated introduction to the Fourier Transform, winding graphs around circles.

Symmetric keys are essential to encrypting messages. How can two people share the same key without someone else getting a hold of it? Upfront asymmetric encryption is one way, but another is Diffie-Hellman key exchange.

We've found a microbe that might someday protect us from malaria parasites, and bees might have help with their jobs soon, thanks to bubble pollination!

TED curator Chris Anderson shares his obsession with questions that no one (yet) knows the answers to. A short intro leads into two questions: Why can't we see evidence of alien life? And how many universes are there?

What is integration? Why is it computed as the opposite of differentiation? What is the fundamental theorem of calculus?

A discovery-oriented introduction to error correction codes.

Computer Color is Broken

Chris Anderson gave this talk in 2002, prior to taking over leadership of TED. Co-founder Richard Saul Wurman was leaving, and TED's future was in the balance. He seeks to persuade TEDsters that what was then a for-profit conference had...

How do you know you're a person who has lived your life, rather than a just-formed brain full of artificial memories, momentarily hallucinating a reality that doesn't actually exist? That may sound absurd, but it's kept several...

The big blue buildings of Ikea have sprouted solar panels and wind turbines; inside, shelves are stocked with LED lighting and recycled cotton. Why? Because as Steve Howard puts it: “Sustainability has gone from a nice-to-do to a...

Though the first written number system can be dated back to 2500 years ago in Mesopotamia, a zero-like symbol did not appear until 7th century CE India. Jessica Oreck and Rachael Teel track the evolution of zero from a dot to the symbol...

The enigmatic equation e^{pi i} = -1 is usually explained using Taylor's formula during a calculus class. This video offers a different perspective, which involves thinking about numbers as actions, and about e^x as something which turns...

Fossils can provide clues to the conditions that ancient species lived in, like what their environments felt like, how deep in the water some species lived, or even how long the Sun was out!

We'll soon be capable of building self-replicating robots. This will not only change humanity's future but reshape the galaxy as we know it.

Imagine you have four cubes, whose faces are colored red, blue, yellow, and green. Can you stack these cubes so that each color appears exactly once on each of the four sides of the stack?

* Viewer discretion advised. This video includes discussion of mature topics and may be inappropriate for some audiences. From our fear of women's bodies to our sheepishness around the word "nipple," our ideas about sex need an upgrade,...

There are a lot of nuclear weapons on Earth, so many that we often say it's enough to "destroy the world several times over." But could we? Well, that depends on what you mean. Also...no matter what you mean, probably not. The Earth is...

In this video Paul Andersen explains how the conservation of mass was replaced with the conservation of mass-energy when it was determined that they are equivalent. This famous equation not only show the mass-energy equivalence but can...

Even though we're all probably very experienced poopers, sometimes we need a little help.

At TED2010, mathematics legend Benoit Mandelbrot develops a theme he first discussed at TED in 1984 -- the extreme complexity of roughness, and the way that fractal math can find order within patterns that seem unknowably complicated.

So the Mars Rovers didn't scoop up any alien lifeforms. Scientist Penelope Boston thinks there's a good chance -- a 25 to 50 percent chance, in fact -- that life might exist on Mars, deep inside the planet's caves. She details how we...

The formula for the cross product can feel like a mystery, or some kind of crazy coincidence. But it isn't. There is a fundamental connection between the cross product and determinants.

In elections, your vote may be influenced by design of the ballot itself, especially when you don’t have strong feelings about which candidate to elect.

Some of the oldest galaxies we’ve ever seen are small, faint satellite galaxies orbiting the Milky Way, and they're providing us with a glimpse of how the universe evolved.