Traditional lab tests for disease diagnosis can be too expensive and cumbersome for the regions most in need. George Whitesides' ingenious answer is a foolproof tool that can be manufactured at virtually zero cost.

Today's refugee crisis is the biggest since World War II, and it's growing. When this talk was given, 50 million people had been forcefully displaced from their homes by conflict and war; now the number is 65.3 million. There were 3...

Digital public servant Amanda Renteria has seen that the millions of people who rely on government welfare services are often discouraged from seeking them out, frustrated by long lines and unnecessarily complicated processes. At Code...

How to Draw a Stick Figure

Hugh evans started a movement that mobilizes "global citizens," people who self-identify first and foremost not as members of a state, nation or tribe but as members of the human race. In this uplifting and personal talk, learn more...

How much do you know about the world? Hans Rosling, with his famous charts of global population, health and income data (and an extra-extra-long pointer), demonstrates that you have a high statistical chance of being quite wrong about...

Since 2000, the annual number of people convicted of crimes in the United States has stayed steady, but the average number of people in jail each year has shot up. How can that be? The answer lies in the bail system— which isn't doing...

We are living in a world that is tantalizingly close to ensuring that no one need die of hunger or malaria or diarrhea, says economist Michael Green. To help spur progress, back in 2015 the United Nations drew up a set of 17 goals around...

Collective compassion has meant an overall decrease in global poverty since the 1980s, says civil rights lawyer Gary Haugen. Yet for all the world's aid money, there's a pervasive hidden problem keeping poverty alive. Haugen reveals the...

Almost a billion people worldwide live in informal communities and slums, often without basic infrastructure like clean water, toilets or adequate roads. Urban planner Smruti Jukur Johari breaks down myths about these communities and...

Rural villages worldwide are being deserted, as billions of people flock to cities to live in teeming squatter camps and slums. Stewart Brand says this is a good thing. Why? It'll take you 3 minutes to find out.

This week we’re taking our discussion of stratification global. We’ll look at First and Third World countries and the reasons why these terms are no longer used. We’ll introduce the four types of country categories we now use: high...

For smallholder farmers in India, agriculture has long been an unreliable source of income -- crops that flourish one season can fail the next, thanks to heat, pests and disease. But climate risk is now making the profession nearly...

Photographs do more than document history -- they make it. At TED University, Jonathan Klein of Getty Images shows some of the most iconic, and talks about what happens when a generation sees an image so powerful it can't look away -- or...

During economic crises, marginalized communities are more susceptible to the harms and struggle that come with these downturns. Today we'll talk about the Great Depression, which lasted from 1929 until the US entered World War II. This...

What makes work satisfying? Apart from a paycheck, there are intangible values that, Barry Schwartz suggests, our current way of thinking about work simply ignores. It's time to stop thinking of workers as cogs on a wheel.

Science can help create understanding where there is none, but is it possible to study and understand terrorists if we're too busy doing everything we can to stop it? Terrorism is notoriously difficult to study because governments...

There's a lot we can learn from Mongolian nomads about how to survive in the years to come, says environmental activist Khulan Batkhuyag. Taking us on a journey through the country's stunning rural landscape, she shows how Mongolian...

What drives someone to kill in cold blood? What goes through the murderer's mind? And what kind of a society breeds such people? Over 150 years ago Fyodor Mikhailovich Dostoyevsky took these questions up in what would become one of the...

Exposing what life looks like in Afghanistan after a 20-year US occupation and the Taliban's stunning and rapid takeover, TED Fellow and documentary photographer Kiana Hayeri captures harrowing glimpses and multifaceted realities of a...

A lack of infrastructure in parts of Africa has made unregulated, gas-powered motorcycle taxis widespread -- a system that gets people where they need to be, but heavily pollutes the air and excludes drivers from the formal economy. TED...

Iqbal Quadir tells how his experiences as a kid in poor Bangladesh, and later as a banker in New York, led him to start a mobile phone operator connecting 80 million rural Bangladeshi -- and to become a champion of bottom-up development.

What can you do to build a better world? Sharing stories from her pioneering career dedicated to tackling poverty, Jacqueline Novogratz offers three principles to spark and sustain a moral revolution. Learn how you can commit (or...

Today we're going to learn about perhaps the best-known leader in the Civil Rights Era, Martin Luther King, Jr. From his rise to notoriety during the Montgomery Bus Boycott in 1955, his leadership of the Southern Christian Leadership...