During the 1600's, the exotic tulip became a nationwide sensation; some single bulbs even sold for ten times the yearly salary of a skilled craftsman. Suddenly, though, the demand completely plummeted, leaving the tulip market in a depression. What happened? Prateek Singh explains the peak of a business cycle, commonly referred to as a mania. [D...

Today's AI algorithms require tens of thousands of expensive medical images to detect a patient's disease. What if we could drastically reduce the amount of data needed to train an AI, making diagnoses low-cost and more effective? TED Fellow Pratik Shah is working on a clever system to do just that. Using an unorthodox AI approach, Shah has deve...

When Nicolas Bourbaki applied to the American Mathematical Society in the 1950s, he was already one of the most influential mathematicians of his time. He'd published articles in international journals and his textbooks were required reading. Yet his application was firmly rejected for one simple reason: Nicolas Bourbaki did not exist. How is th...

What really causes addiction -- to everything from cocaine to smart-phones? And how can we overcome it? Johann Hari has seen our current methods fail firsthand, as he has watched loved ones struggle to manage their addictions. He started to wonder why we treat addicts the way we do -- and if there might be a better way. As he shares in this deep...

Humorist John Hodgman rambles through a new story about aliens, physics, time, space and the way all of these somehow contribute to a sweet, perfect memory of falling in love.

In a wildly entertaining discussion with Richard Saul Wurman, architect Frank Gehry gives TEDsters his take on the power of failure, his recent buildings, and the all-important "Then what?" factor.

For the majority of recorded human history, units like the weight of a grain or the length of a hand weren't exact and varied from place to place. Now, consistent measurements are such an integral part of our daily lives that it's hard to appreciate what a major accomplishment for humanity they've been. Matt Anticole traces the wild history of t...

When the son of the president of a desperately poor country starts buying mansions and sportscars on an official monthly salary of $7,000, Charmian Gooch suggests, corruption is probably somewhere in the picture. In a blistering, eye-opening talk (with several specific examples), she details how global corruption trackers follow the money -- to ...

In the African grasslands, a gazelle suffering from tuberculosis takes its last breath. The animal's corpse threatens to infect the water, but for the vulture, this isn't a problem: it's a feast. With a stomach of steel that can digest diseased meat and waste, vultures are essential to removing dangerous pathogens from ecosystems. Kenny Coogan e...

Whether or not you realize it, surfers are masters of complicated physics. The science of surfing begins as soon as a board first hits the water. Surfers may not be thinking about weather patterns in the Pacific, tectonic geology or fluid mechanics, but the art of catching the perfect wave relies on all these things and more. Nick Pizzo dives in...

We feel instinctively that societies with huge income gaps are somehow going wrong. Richard Wilkinson charts the hard data on economic inequality, and shows what gets worse when rich and poor are too far apart: real effects on health, lifespan, even such basic values as trust.

Medical, legal, and financial documents should be easy to read, but too often they aren't. With spot-on (and funny) examples, Sandra Fisher Martins shows how overly complex language separates us from the information we need -- and three steps to change that. In Portuguese with English subtitles.

Janet Echelman found her true voice as an artist when her paints went missing -- which forced her to look to an unorthodox new art material. Now she makes billowing, flowing, building-sized sculpture with a surprisingly geeky edge. A transporting 10 minutes of pure creativity.

Ink that conducts electricity; a window that turns from clear to opaque at the flip of a switch; a jelly that makes music. All this stuff exists, and Catarina Mota says: It's time to play with it. Mota leads us on a tour of surprising and cool new materials, and suggests that the way we'll figure out what they're good for is to experiment, tinke...

We've heard a lot of rhetoric lately suggesting that countries like the US are losing valuable manufacturing jobs to lower-cost markets like China, Mexico and Vietnam -- and that protectionism is the best way forward. But those jobs haven't disappeared for the reasons you may think, says border and logistics specialist Augie Picado. He gives us ...

To design the Bahá'í Temple of South America, architect Siamak Hariri focused on illumination -- from the temple's form, which captures the movement of the sun throughout the day, to the iridescent, luminous stone and glass used to construct it. Join Hariri for a journey through the creative process, as he explores what makes for a sacred experi...

It takes an entire civilization to build a toaster. Designer Thomas Thwaites found out the hard way, by attempting to build one from scratch: mining ore for steel, deriving plastic from oil ... it's frankly amazing he got as far as he got. A parable of our interconnected society, for designers and consumers alike.

Cybercrime netted a whopping $450 billion in profits last year, with 2 billion records lost or stolen worldwide. Security expert Caleb Barlow calls out the insufficiency of our current strategies to protect our data. His solution? We need to respond to cybercrime with the same collective effort as we apply to a health care crisis, sharing timely...

Written language, the hallmark of human civilization, didn't just suddenly appear one day. Thousands of years before the first fully developed writing systems, our ancestors scrawled geometric signs across the walls of the caves they sheltered in. Paleoanthropologist, rock art researcher and TED Senior Fellow Genevieve von Petzinger has studied ...

AI is massively transforming our world, but there's one thing it cannot do: love. In a visionary talk, computer scientist Kai-Fu Lee details how the US and China are driving a deep learning revolution -- and shares a blueprint for how humans can thrive in the age of AI by harnessing compassion and creativity. "AI is serendipity," Lee says. "It i...

Sarah Kaminsky tells the extraordinary story of her father Adolfo and his activity during World War II -- using his ingenuity and talent for forgery to save lives.

Around the world right now, one billion people are trapped in poor or failing countries. How can we help them? Economist Paul Collier lays out a bold, compassionate plan for closing the gap between rich and poor.

Why do we still think that drug use is a law-enforcement issue? Making drugs illegal does nothing to stop people from using them, says public health expert Mark Tyndall. So, what might work? Tyndall shares community-based research that shows how harm-reduction strategies, like safe-injection sites, are working to address the drug overdose crisis.

Every seven years, designer Stefan Sagmeister closes his New York studio for a yearlong sabbatical to rejuvenate and refresh their creative outlook. He explains the often overlooked value of time off and shows the innovative projects inspired by his time in Bali.

How can we begin to address the global, insidious problem of climate change — a problem that's too big for any one country to solve? Economist Nicholas Stern lays out a plan, presented to the UN's Climate Summit in 2014, showing how the world's countries can work together on climate. It's a big vision for cooperation, with a payoff that goes far...

Is the War on Drugs doing more harm than good? In a bold talk, drug policy reformist Ethan Nadelmann makes an impassioned plea to end the "backward, heartless, disastrous" movement to stamp out the drug trade. He gives two big reasons we should focus on intelligent regulation instead.

Have you ever doubted your abilities, feared you were going to be discovered as a "fraud"? That's called "impostor syndrome," and you're definitely not alone in feeling it, says entrepreneur and CEO Mike Cannon-Brookes. In this funny, relatable talk, he shares how his own experiences of impostor syndrome helped pave the way to his success -- and...

Physicist Geoffrey West has found that simple, mathematical laws govern the properties of cities -- that wealth, crime rate, walking speed and many other aspects of a city can be deduced from a single number: the city's population. In this mind-bending talk from TEDGlobal he shows how it works and how similar laws hold for organisms and corporat...

"I sell dreams, and I peddle love to millions of people," says Shah Rukh Khan, Bollywood's biggest star. In this charming, funny talk, Khan traces the arc of his life, showcases a few of his famous dance moves and shares hard-earned wisdom from a life spent in the spotlight.

How can we measure what makes a school system work? Andreas Schleicher walks us through the PISA test, a global measurement that ranks countries against one another -- then uses that same data to help schools improve. Watch to find out where your country stacks up, and learn the single factor that makes some systems outperform others.