How does the metaphorical lightbulb go off? Is it a flash of genius? The power of crowds? These heady talks explore the nature of ideas themselves: Where they come from, how they evolve, and how each of us can nurture them.

From Twitter to word of mouth, explore the ways ideas spread so quickly from person to person.

A collaboration between Great Big Story and TED, this series reveals the incredible things that happen when someone unveils an idea so inspiring it moves others to act. Watch the stories of people whose lives have been intrinsically changed by the idea in a TED Talk.

These powerful talks offer ideas for rethinking—and hopefully stopping—the spread of HIV and AIDS.

With all the intensity and brilliance for which he is known, Alan Kay envisions better techniques for teaching kids by using computers to illustrate experience in ways -– mathematically and scientifically -- that only computers can.

Nandan Nilekani, the visionary co-founder of outsourcing pioneer Infosys, explains four brands of ideas that will determine whether India can continue its recent breakneck progress.

The Year In Ideas 2015.

What do 24,000 ideas look like? Ecologist Eric Berlow and physicist Sean Gourley apply algorithms to the entire archive of TEDx Talks, taking us on a stimulating visual tour to show how ideas connect globally.

At TEDGlobal 2010, author Matt Ridley shows how, throughout history, the engine of human progress has been the meeting and mating of ideas to make new ideas. It's not important how clever individuals are, he says; what really matters is how smart the collective brain is.

Great incubators of innovations are not limited to garages in Silicon Valley. Manov Subodh charts three principles for sparking entrepreneurial ventures and ideas in people around the world. From dreaming big to getting over the fear of failure, he offers case studies that guide us through the whole process.

Being alone takes its toll. Feel like it's time to make a real connection? Third-wheel with Rainn Wilson (star of "The Office") as he dates some of the best ideas on TED.com and discover your perfect "idea mate" along the way.

Huge ideas from physics.

The "dismal science" truly shines in this optimistic talk, as economist Alex Tabarrok argues free trade and globalization are shaping our once-divided world into a community of idea-sharing more healthy, happy and prosperous than anyone's predictions.

These talks pull interesting ideas out of shocking crimes.

Few individuals have influenced the world and many of today's thinkers like Plato. He created the first Western university and was teacher to Ancient Greece's greatest minds, including Aristotle. But even he wasn't perfect. Along with his great ideas, Plato had a few that haven't exactly stood the test of time. Wisecrack gives a brief rundown of...

Amazing inventions, activism and tons of genius delivered by an awesome group of kids and teens.

Hannah Gadsby's groundbreaking special "Nanette" broke comedy. In a talk about truth and purpose, she shares three ideas and three contradictions. Or not.

People often credit their ideas to individual "Eureka!" moments. But Steven Johnson shows how history tells a different story. His fascinating tour takes us from the "liquid networks" of London's coffee houses to Charles Darwin's long, slow hunch to today's high-velocity web.

The enduring ideas, discoveries and observations that define and expand life as we know it.

Inspiring words -- and smart ideas -- about standing up for yourself, even when it seems impossible.

From the TED archives: The legendary graphic designer Milton Glaser dives deep into a new painting inspired by Piero della Francesca. From here, he muses on what makes a convincing poster, by breaking down an idea and making it new.

Adam Savage walks through two spectacular examples of profound scientific discoveries that came from simple, creative methods anyone could have followed -- Eratosthenes' calculation of the Earth's circumference around 200 BC and Hippolyte Fizeau's measurement of the speed of light in 1849.

In a world of too many options and too little time, our obvious choice is to just ignore the ordinary stuff. Marketing guru Seth Godin spells out why, when it comes to getting our attention, bad or bizarre ideas are more successful than boring ones.

Out of fresh ideas? These inspiring talks offer the kick-in-the-pants you need to unleash your creative spirit.

Designer Philippe Starck handpicked this list of talks about science and design -- ideas that spur imagination and inspire creativity.

Education legend Sir Ken Robinson picked the talks he loves — all full of insight, bright ideas and, of course, creativity.

How being bored can lead to new possibilities, better ideas and even an extra shot of creativity.

The Audacious Project is TED's collaborative experiment to put bold ideas for social change into action. Learn more at AudaciousProject.org.

Easy, straightforward techniques to jumpstart innovative thinking and surface new, brilliant ideas.

Shimpei Takahashi always dreamed of designing toys. But when he started work as a toy developer, he found that the pressure to produce squashed his creativity. In this short, funny talk, Takahashi describes how he got his ideas flowing again, and shares a simple word game anyone can play to generate new ideas. (In Japanese with English subtitles.)