"I dream of a world where geography classes teach about the climate crisis as this one great challenge that was won by people like you and me," says climate activist Luisa Neubauer. With Greta Thunberg, Neubauer helped initiate "Fridays For Future," the momentous international school strike movement that protests the lack of action on the climat...

You'd never know from her transformation into the death-dealing Arya Stark on "Game of Thrones" that Maisie Williams' childhood dream was to become a professional dancer. In this personal talk, she maps out the winding path that took her from dance lessons and local talent competitions to the world's most popular TV show. The lesson she learned ...

Explore a speculative digital world without screens in this fanciful demo, a mix of near reality and far-future possibility. Wearing the HoloLens headset, Alex Kipman demos his vision for bringing 3D holograms into the real world, enhancing our perceptions so that we can touch and feel digital content. Featuring Q&A with TED's Helen Walters.

Before life existed on Earth, there was just matter, inorganic dead "stuff." How improbable is it that life arose? And -- could it use a different type of chemistry? Using an elegant definition of life (anything that can evolve), chemist Lee Cronin is exploring this question by attempting to create a fully inorganic cell using a "Lego kit" of in...

Oxford philosopher and transhumanist Nick Bostrom examines the future of humankind and asks whether we might alter the fundamental nature of humanity to solve our most intrinsic problems.

Artificial intelligence is all around us ... and the future will only bring more of it. How can we ensure the AI systems we build are responsible, safe and sustainable? Ethical AI expert Genevieve Bell shares six framing questions to broaden our understanding of future technology -- and create the next generation of critical thinkers and doers.

Speaking as both an astronomer and "a concerned member of the human race," Sir Martin Rees examines our planet and its future from a cosmic perspective. He urges action to prevent dark consequences from our scientific and technological development.

Eric Topol says we'll soon use our smartphones to monitor our vital signs and chronic conditions. At TEDMED, he highlights several of the most important wireless devices in medicine's future -- all helping to keep more of us out of hospital beds.

What we see in movies matters: it affects our hobbies, our career choices, our emotions and even our identities. Right now, we don't see enough women on screen or behind the camera -- but waiting for Hollywood to grow a conscience isn't going to fix the problem, says Naomi McDougall Jones. Join forces with the actor and activist as she outlines ...

British MP Rory Stewart walked across Afghanistan after 9/11, talking with citizens and warlords alike. Now, a decade later, he asks: Why are Western and coalition forces still fighting there? He shares lessons from past military interventions that worked -- Bosnia, for instance -- and shows that humility and local expertise are the keys to succ...

It sounds like science fiction, but journalist Stephen Petranek considers it fact: within 20 years, humans will live on Mars. In this provocative talk, Petranek makes the case that humans will become a spacefaring species and describes in fascinating detail how we'll make Mars our next home. "Humans will survive no matter what happens on Earth,"...

What controls aging? Biochemist Cynthia Kenyon has found a simple genetic mutation that can double the lifespan of a simple worm, C. elegans. The lessons from that discovery, and others, are pointing to how we might one day significantly extend youthful human life.

Researcher Hans Rosling uses his cool data tools to show how countries are pulling themselves out of poverty. He demos Dollar Street, comparing households of varying income levels worldwide. Then he does something really amazing.

Astronomers once gazed upon the night sky and counted every star in the galaxy by hand. The process has evolved since then, but the thirst for celestial knowledge remains the same. Join astrophysicist Emily Levesque for an anecdote-rich jaunt through the technological history of photographing the cosmos and learn about the one constant that make...

Before he was a legend, architect Frank Gehry takes a whistlestop tour of his early work, from his house in Venice Beach to the American Center in Paris, which was under construction (and much on his mind) when he gave this talk.

You want to eat a more climate-friendly diet but you're not ready to be vegan or vegetarian? That's OK, says entrepreneur Brian Kateman. Instead, you could be a "reducetarian" — someone who's making the conscious choice to decrease the amount of meat they consume. In this talk, he explains the costs of our current diets and the benefits that ada...

Former "young Republican" Larry Lessig talks about what Democrats can learn about copyright from their opposite party, considered more conservative. A surprising lens on remix culture.

Legendary skeptic James Randi takes a fatal dose of homeopathic sleeping pills onstage, kicking off a searing 18-minute indictment of irrational beliefs. He throws out a challenge to the world's psychics: Prove what you do is real, and I'll give you a million dollars. (No takers yet.)

Vincent Cochetel was held hostage for 317 days in 1998, while working for the UN High Commissioner on Refugees in Chechnya. For the first time, he recounts the experience — from what it was like to live in a dark, underground chamber, chained to his bed, to the unexpected conversations he had with his captors. With lyricism and power, he explain...

Our universe is strange, wonderful and vast, says astronomer Natasha Hurley-Walker. A spaceship can't carry you into its depths (yet) -- but a radio telescope can. In this mesmerizing talk, Hurley-Walker shows how she probes the mysteries of the universe using special technology that reveals light spectrums we can't see.

At the INK Conference, Arvind Gupta shares simple yet stunning plans for turning trash into seriously entertaining, well-designed toys that kids can build themselves -- while learning basic principles of science and design.

There is a corruption at the heart of American politics, caused by the dependence of Congressional candidates on funding from the tiniest percentage of citizens. That's the argument at the core of this blistering talk by legal scholar Lawrence Lessig. With rapid-fire visuals, he shows how the funding process weakens the Republic in the most fund...

"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.

The public displays of affection that straight couples take for granted every day can be outright dangerous for queer couples to practice -- what do you do when simply holding hands with a loved one can be considered a political act? Irish activist Panti Bliss shares what it's like to navigate such a world and highlights the importance of normal...

James Surowiecki pinpoints the moment when social media became an equal player in the world of news-gathering: the 2005 tsunami, when YouTube video, blogs, IMs and txts carried the news -- and preserved moving personal stories from the tragedy.

When Bran Ferren was just 9, his parents took him to see the Pantheon in Rome — and it changed everything. In that moment, he began to understand how the tools of science and engineering become more powerful when combined with art, with design and beauty. Ever since, he's been searching for a convincing modern-day equivalent to Rome's masterpiec...

Have you wondered why politicians aren't what they used to be, why governments seem unable to solve real problems? Economist Yanis Varoufakis, the former Minister of Finance for Greece, says that it's because you can be in politics today but not be in power -- because real power now belongs to those who control the economy. He believes that the ...

In tough economic times, our exploratory science programs -- from space probes to the LHC -- are first to suffer budget cuts. Brian Cox explains how curiosity-driven science pays for itself, powering innovation and a profound appreciation of our existence.

In 2011 three young women swept the top prizes of the first Google Science Fair. Lauren Hodge, Shree Bose and Naomi Shah describe their extraordinary projects -- and their route to a passion for science.

While we like to imagine little green men, it's far more likely that life on other planets will be microbial. Planetary scientist Nathalie Cabrol takes us inside the search for microbes on Mars, a hunt which counterintuitively leads us to the remote lakes of the Andes mountains. This extreme environment — with its thin atmosphere and scorched la...