TED.com

The days are past (if they ever existed) when a person, company or brand could tightly control their reputation -- online chatter and spin mean that if you're relevant, there's a constant, free-form conversation happening about you that you have no control over. Tim Leberecht offers three big ideas about accepting that loss of control, even designing for it -- and using it as an impetus to recommit to your values.

As the director of the Metropolitan Museum of Art in New York, Thomas P. Campbell thinks deeply about curating—not just selecting art objects, but placing them in a setting where the public can learn their stories. With glorious images, he shows how his curation philosophy works for displaying medieval tapestries—and for the over-the-top fashion/art of Alexander McQueen. (From The Design Studio session at TED2012, guest-curated by Chee Pearlman and David Rockwell.)

Shimon Schocken and Noam Nisan developed a curriculum for their students to build a computer, piece by piece. When they put the course online -- giving away the tools, simulators, chip specifications and other building blocks -- they were surprised that thousands jumped at the opportunity to learn, working independently as well as organizing their own classes in the first Massive Open Online Course (MOOC). A call to forget about grades and tap into the self-motivation to learn.

In this gripping talk, lawyer Jason McCue urges for a new way to attack terrorism, to weaken its credibility with those who are buying the product -- the recruits. He shares stories of real cases where he and other activists used this approach to engage and create change.

When Robert Gupta was caught between a career as a doctor and as a violinist, he realized his place was in the middle, with a bow in his hand and a sense of social justice in his heart. He tells a moving story of society’s marginalized and the power of music therapy, which can succeed where conventional medicine fails.

Body language affects how others see us, but it may also change how we see ourselves. Social psychologist Amy Cuddy shows how “power posing” -- standing in a posture of confidence, even when we don’t feel confident -- can affect testosterone and cortisol levels in the brain, and might even have an impact on our chances for success.

Set aside the politics: Data shows that climate change is happening, measurably, now. And as Vicki Arroyo says, it's time to prepare our homes and cities for the new climate, with its increased risk of flooding, drought and uncertainty. She illustrates this inspiring talk with bold projects from cities all over the world -- local examples of thinking ahead.

Map designer Aris Venetikidis is fascinated by the maps we draw in our minds as we move around a city -- less like street maps, more like schematics or wiring diagrams, abstract images of relationships between places. How can we learn from these mental maps to make better real ones? As a test case, he remakes the notorious Dublin bus map. (Filmed at TEDxDublin)

Art historian Bahia Shehab has long been fascinated with the Arabic script for ‘no.’ When revolution swept through Egypt in 2011, she began spraying the image in the streets saying no to dictators, no to military rule and no to violence.

When a new drug gets tested, the results of the trials should be published for the rest of the medical world -- except much of the time, negative or inconclusive findings go unreported, leaving doctors and researchers in the dark. In this impassioned talk, Ben Goldacre explains why these unreported instances of negative data are especially misleading and dangerous.

The open-source world has learned to deal with a flood of new, oftentimes divergent, ideas using hosting services like GitHub -- so why can’t governments? In this rousing talk Clay Shirky shows how democracies can take a lesson from the Internet, to be not just transparent but also to draw on the knowledge of all their citizens.

Mice, bugs and hamsters are no longer the only way to study the brain. Functional MRI (fMRI) allows scientists to map brain activity in living, breathing, decision-making human beings. Read Montague gives an overview of how this technology is helping us understand the complicated ways in which we interact with each other.

Robots and algorithms are getting good at jobs like building cars, writing articles, translating -- jobs that once required a human. So what will we humans do for work? Andrew McAfee walks through recent labor data to say: We ain't seen nothing yet. But then he steps back to look at big history, and comes up with a surprising and even thrilling view of what comes next. (Filmed at TEDxBoston.)

There's been an explosion of collaborative consumption -- web-powered sharing of cars, apartments, skills. Rachel Botsman explores the currency that makes systems like Airbnb and Taskrabbit work: trust, influence, and what she calls "reputation capital."

One day, Ed Gavagan was sitting on the subway, watching two young med students practicing their knots. And a powerful memory washed over him -- of one shocking moment that changed his life forever. An unforgettable story of crime, skill and gratitude.

Your mobile phone, computer and game console have a bloody past — tied to tantalum mining, which funds the war in the Democratic Republic of the Congo. Drawing on his personal story, activist and refugee Bandi Mbubi gives a stirring call to action. (Filmed at TEDxExeter.)

When a squirrel chewed through a cable and knocked him offline, journalist Andrew Blum started wondering what the Internet was really made of. So he set out to go see it -- the underwater cables, secret switches and other physical bits that make up the net.

Because of poor acoustics, students in classrooms miss 50 percent of what their teachers say and patients in hospitals have trouble sleeping because they continually feel stressed. Julian Treasure sounds a call to action for designers to pay attention to the “invisible architecture” of sound.

Why do teenagers seem so much more impulsive, so much less self-aware than grown-ups? Cognitive neuroscientist Sarah-Jayne Blakemore compares the prefrontal cortex in adolescents to that of adults, to show us how typically “teenage” behavior is caused by the growing and developing brain.

Western countries throw out nearly half of their food, not because it’s inedible -- but because it doesn’t look appealing. Tristram Stuart delves into the shocking data of wasted food, calling for a more responsible use of global resources.