We've known for millennia that lead pipes could make us sick, so why are we still drinking from them?

The Red Planet was once more like Earth, with a thicker atmosphere and liquid water. Now, scientists are looking for clues to its past in the planet’s ancient fossil dunes, barchan dunes, and ghost dunes.

Josette Sheeran, the head of the UN's World Food Program, talks about why, in a world with enough food for everyone, people still go hungry, still die of starvation, still use food as a weapon of war. Her vision: "Food is one issue that...

Anything that is worth pursuing is going to require us to suffer, just a little bit, says surf photographer Chris Burkard, as he explains his obsession with the coldest, choppiest, most isolated beaches on earth. With jawdropping photos...

A founding member of the Axis of Evil Comedy Tour, standup comic Maz Jobrani riffs on the challenges and conflicts of being Iranian-American -- "like, part of me thinks I should have a nuclear program; the other part thinks I can't be...

It's getting really cold where Jessi and Squeaks live, and that has her thinking about a super cool animal that's always ready for super cold weather: Reindeer!

America was built by makers -- curious, enthusiastic amateur inventors whose tinkering habit sparked whole new industries. At TED@MotorCity, MAKE magazine publisher Dale Dougherty says we're all makers at heart, and shows cool new tools...

In which John Green teaches you about water! So, we talk about resources a lot on Crash Course, and today is no exception. It turns out people can't live without water, which means it's absolutely necessary for civilization. Today John...

Hank tells us four incredible things about Jupiter's sixth moon, Europa.

If you're a Pokémon super-fan seeing Detective Pikachu this weekend, a little bit of your brain might light up that won’t light up in the brains of those that didn’t try to catch 'em all! Find out why that's important to understanding...

More and more people worldwide are living in countries not considered their own. Writer Pico Iyer -- who himself has three or four “origins” -- meditates on the meaning of home, the joy of traveling and the serenity of standing still.

For the last hundred and fifty years or so, geologists have been trying to wrap their heads around the mystery: in some places, the geologic record just seems to jump by over billion years. And last week, a paper was published that may...

You might not want to sign up for the Enceladus Ice Hockey League... And some researchers have an idea that might make the Big Bang model more accurate!

A meteorite crashed into earth!!!! This wasn't the first time and it won't be the last, but it is the first time such an event was captured by SO MANY CAMERAS! But besides providing the world with some hilarious, frightening, and amazing...

You might have realized that lots of ground-based telescopes are located in Hawaii...but why? It's not just for the beautiful sunsets.

Today, we all do our best to protect ourselves from coronaviruses. But a lot of what people are doing doesn’t really help, and it could take away supplies from those who actually need them. Hank explains what does help, and how it...

Today we wrap up the first half of our series on physical geography by taking a closer look at natural hazards - which are physical processes like heat waves and cyclones, earthquakes and volcanic eruptions, and floods and droughts. And...

The average global temperature is on the rise, evidenced by the ten warmest years on record happening since 2005. But this isn’t just about greenhouse gases preventing heat from escaping. Another culprit comes in the form of…clouds.

We're not doing frontline exploratory science in a huge portion of the world -- the places governments deem too hostile or disputed. What might we be missing because we're not looking? In this fearless, unexpectedly funny talk,...

Squeaks and Jessi are spending the afternoon playing "Guess That Animal" and learning about some of their favorites!

You don't have to be a scientist to help protect the world's oceans, says underwater drone expert and TED Fellow David Lang -- in fact, ordinary citizens have pulled together to save the planet's natural treasures many times in history....

Over the course of hundreds of scuba dives, marine biologist Ayana Elizabeth Johnson fell in love -- with a fish. In this ode to parrotfish, she shares five reasons why these creatures are simply amazing (from their ability to poop white...

When birds and squirrels cache food for the winter, it means they have to remember where to find that food later. Their strategies for finding their hidden feasts includes memory tricks and changing brains.

Scientists can find answers in some pretty unusual places, and recently they found some evidence that dinosaurs weren't cold-blooded by looking at... eggshells?