Data can be used for good, harnessed for the betterment of society, but it can also be abused. Find out about some hidden not-so-sunny uses of Big Data.

When Dick Fosbury couldn't compete against the skilled high jumpers at his college, he tried jumping in a different way -- backwards. Fosbury improved his record immediately and continued to amaze the world with his new technique all the way to Olympic gold. Asaf Bar-Yosef explains the physics behind the success of the now dominant Fosbury Flop....

In the year leading up to this talk, the web tool Twitter exploded in size (up 10x during 2008 alone). Co-founder Evan Williams reveals that many of the ideas driving that growth came from unexpected uses invented by the users themselves.

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.

Rather than demo another new technology, Tom Wujec reaches back to one of our earliest but most ingenious devices -- the astrolabe. With thousands of uses, from telling time to mapping the night sky, this old tech reminds us that the ancient can be as brilliant as the brand-new.

French street artist JR uses his camera to show the world its true face, by pasting photos of the human face across massive canvases. At TED2011, he makes his audacious TED Prize wish: to use art to turn the world inside out.

To study a system as complex as the entire universe, astrophysicists need to be experts at extracting simple solutions from large data sets. What else could they do with this expertise? In an interdisciplinary talk, TED Fellow and astrophysicist Federica Bianco explains how she uses astrophysical data analysis to solve urban and social problems ...

Logistics expert Katie Francfort invites us to dream of finding solutions in unexpected places. In this thought experiment, she imagines: What if mosquitoes could have a role to play in the supply chain of vaccine delivery? She uses this far-fetched idea to inspire us to think boldly on other problems we're facing -- and how the problem might be...

Alejandro Durán uses art to spotlight the ongoing destruction of our oceans' ecosystems. In this breathtaking talk, he shows how he meticulously organizes and reuses plastic waste from around the world that washes up on the Caribbean coast of Mexico -- everything from water bottles to prosthetic legs -- to create vivid, environmental artworks th...

In 1970, marijuana was classified as a schedule 1 drug in the United States: the strictest designation possible, meaning it was completely illegal and had no recognized medical uses. Today, marijuana's therapeutic benefits are widely acknowledged, but a growing recognition for its medical value doesn't answer the question: is recreational mariju...

In this quick, witty performance, TED Fellow and comedian Carl Joshua Ncube uses humor to point out some culturally taboo topics from his home country of Zimbabwe.

In this fun, 3-min performance from the World Science Festival, musician Bobby McFerrin uses the pentatonic scale to reveal one surprising result of the way our brains are wired.

In a timely talk, cultural critic Virginia Postrel muses on the true meaning, and the powerful uses, of glamour -- which she defines as any calculated, carefully polished image designed to impress and persuade.

Accepting his 2007 TED Prize, war photographer James Nachtwey shows his life's work and asks TED to help him continue telling the story with innovative, exciting uses of news photography in the digital era.

Behavioral economist Dan Ariely, the author of Predictably Irrational, uses classic visual illusions and his own counterintuitive (and sometimes shocking) research findings to show how we're not as rational as we think when we make decisions.

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.

It may seem that big problems require big solutions, but ad man Rory Sutherland says many flashy, expensive fixes are just obscuring better, simpler answers. To illustrate, he uses behavioral economics and hilarious examples.

In this joke-laden talk, Kasha Patel uses the standup comedy format to make a case for combining science communication with humor in order to make the former more accessible and the latter more educational.

At 18, Natalie Warne's work with the Invisible Children movement made her a hero for young activists. She uses her inspiring story to remind us that no one is too young to change the world.

I wish for us to discover the millions of unknown archaeological sites across the globe. By building an online citizen science platform and training a 21st century army of global explorers, we'll find and protect the world's hidden heritage, which contains clues to humankind's collective resilience and creativity. The plan What would happen if I...

Erik Johansson creates realistic photos of impossible scenes -- capturing ideas, not moments. In this witty how-to, the Photoshop wizard describes the principles he uses to make these fantastical scenarios come to life, while keeping them visually plausible.

Artist Uldus Bakhtiozina uses photographs to poke fun at societal norms in her native Russia. A glimpse into Russian youth culture and a short, fun reminder not to take ourselves too seriously.

Talking at the US State Department this summer, Hans Rosling uses his fascinating data-bubble software to burst myths about the developing world. Look for new analysis on China and the post-bailout world, mixed with classic data shows.

Producer, songwriter, beatboxer and vocal arranger MaJiKer uses his whole body to express himself musically. Here, he premieres an experimental new piece that combines piano (occasionally played with his foot and head) with beatboxing, to wild effect.

Fiorenzo Omenetto shares 20+ astonishing new uses for silk, one of nature's most elegant materials -- in transmitting light, improving sustainability, adding strength and making medical leaps and bounds. On stage, he shows a few intriguing items made of the versatile stuff.

In his typically candid style, Richard St. John reminds us that success is not a one-way street, but a constant journey. He uses the story of his business' rise and fall to illustrate a valuable lesson -- when we stop trying, we fail.

Golan Levin, an artist and engineer, uses modern tools -- robotics, new software, cognitive research -- to make artworks that surprise and delight. Watch as sounds become shapes, bodies create paintings, and a curious eye looks back at the curious viewer.

Nature photographer Frans Lanting uses vibrant images to take us deep into the animal world. In this short, visual talk he calls for us to reconnect with other earthly creatures, and to shed the metaphorical skins that separate us from each other.

Mona Lisa is one of the best-known faces on the planet. But would you recognize an image of Leonardo da Vinci? Illustrator Siegfried Woldhek uses some thoughtful image-analysis techniques to find what he believes is the true face of Leonardo.

Gever Tulley uses engaging photos and footage to demonstrate the valuable lessons kids learn at his Tinkering School. When given tools, materials and guidance, these young imaginations run wild and creative problem-solving takes over to build unique boats, bridges and even a roller coaster!