TED-Ed

Uncover the history of the ancient underground cities beneath Cappadocia, which were built during the Byzantine Empire.--The breathtaking geological formations of Cappadocia are one of the most astonishing landscapes on Earth. Also known as “fairy chimneys,” this impressive terrain hides an equally remarkable feat of pre-modern engineering: a network of extensive underground cities stretching deep...

View full lesson: http://ed.ted.com/lessons/how-state-budgets-are-breaking-us-schools-bill-gatesAmerica's school systems are funded by the 50 states. In this fiery talk, Bill Gates says that state budgets are riddled with accounting tricks that disguise the true cost of health care and pensions and weighted with worsening deficits -- with the financing of education at the losing end. Talk by Bill...

Dig into the Greek myth of Mestra and her father King Erysichthon, who angered the gods and was cursed with insatiable hunger.--Mestra, princess of Thessaly, was far from home. She had watched her father, King Erysichthon, plunge into a ruin of his own making. Now, to save himself, he’d sold his own daughter to the highest bidder. But Mestra refused to accept this fate and began to plan her escape...

Dig into the distinction between a language and a dialect, and uncover the history of standardized languages.--Outside of China, Mandarin and Cantonese are often referred to as Chinese dialects, despite being even more dissimilar than Spanish and Italian. On the other hand, speakers of Danish, Norwegian, and Swedish, which are three distinct languages, can usually communicate with each other in th...

View full lesson: http://ed.ted.com/lessons/fractals-and-the-art-of-roughness-benoit-mandelbrotAt TED2010, mathematics legend Benoit Mandelbrot develops a theme he first discussed at TED in 1984 -- the extreme complexity of roughness and the way that fractal math can find order within patterns that seem unknowably complicated. Talk by Benoit Mandelbrot. Learn more about your ad choices. Visit mega...

What could our future world look like if we continue to do nothing about climate change? Take a look at the possibilities.--While we’re already feeling the devastating effects of human-caused climate change, governments continue to fall short on making and executing emissions pledges that would help thwart further warming. So, what will our world look like in the next 30 to 80 years, if we continu...

View full lesson: http://ed.ted.com/lessons/a-3d-atlas-of-the-universe-carter-emmartFor the last 12 years, Carter Emmart has been coordinating the efforts of scientists, artists and programmers to build a complete 3D visualization of our known universe. He demos this stunning tour and explains how it's being shared with facilities around the world. Talk by Carter Emmart. Learn more about your ad c...

Explore why earwax forms, its purpose in our health, and whether or not we should be trying to get rid of it.--Grooming paraphernalia has been found in numerous archeological sites, many of which have included earwax removal tools. And earwax evacuation remains a popular hygienic habit today. But what is earwax? And are the efforts to eliminate it actually good for us? Henry C. Ou explores the imp...

Massimo Banzi helped invent the Arduino, a tiny, easy-to-use open-source microcontroller that's inspired thousands of people around the world to make the coolest things they can imagine -- from toys to satellite gear. Because, as he says, "You don't need anyone's permission to make something great." Talk by Massimo Banzi. Learn more about your ad choices. Visit megaphone.fm/adchoices

Margaret Gould Stewart, YouTube's head of user experience, talks about how the ubiquitous video site works with copyright holders and creators to foster (at the best of times) a creative ecosystem where everybody wins. Talk by Margaret Gould Stewart. Learn more about your ad choices. Visit megaphone.fm/adchoices

Explore Edvard Munch’s masterpiece “The Scream,” and find out why this artwork became one of the world’s most famous paintings.--An undulating sky melds into the landscape, two silhouettes move along a balustraded walkway, and a ghostly figure’s features extend in agony. Since Norwegian artist Edvard Munch created "The Scream" in 1893, it’s become one of the world’s most famous artworks. But why h...

Explore the phenomenon and uses of chlorophyll fluorescence, a small amount of light emitted by plants during photosynthesis.--In 2009, a satellite circled Earth, scanning and sorting the wavelengths reflecting off the planet’s surface. Researchers noticed something baffling: an unexpected wavelength of unknown origin. They tried looking at Earth with only this wavelength, and saw the planet cover...

View full lesson: http://ed.ted.com/lessons/mysteries-of-vernacular-quarantine-jessica-oreck-and-rachael-teelStemming from the days of bubonic plague in Medieval Europe, quarantines were originally used to prevent potentially plague-infested ships from disembarking at a port city. Jessica Oreck and Rachael Teel explain how the length of the wait, often 40 days, came to be associated with the word...

View full lesson: http://ed.ted.com/lessons/the-pattern-behind-self-deception-michael-shermerMichael Shermer says the human tendency to believe strange things -- from alien abductions to dowsing rods -- boils down to two of the brain's most basic, hard-wired survival skills. He explains what they are and how they get us into trouble. Talk by Michael Shermer. Learn more about your ad choices. Visit...

Dig into one of Japan’s most infamous stories about the 47 samurai who take revenge for the loss of their leader.--Asano Naganori, lord of Akō domain, fixed his gaze on Kira Yoshinaka, a senior master of ceremony. Asano extended his short sword, charged through the castle, and struck Kira. While the wound wasn’t fatal, its consequences would be. What brought about this violent quarrel? And what wo...

View full lesson: http://ed.ted.com/lessons/how-architecture-helped-music-evolve-david-byrneAs his career grew, David Byrne went from playing CBGB to Carnegie Hall. He asks: Does the venue make the music? From outdoor drumming to Wagnerian operas to arena rock, he explores how context has pushed musical innovation. Talk by David Byrne. Learn more about your ad choices. Visit megaphone.fm/adchoices

Explore common types of corruption and find out what we can do to combat it and promote transparency in our institutions.--Corruption is often defined as misuse of a position of power for personal gain. And while corruption in politics is nothing new, it isn’t limited to the political sphere; it can happen in schools, sports, businesses, or religious institutions. So, what exactly is corruption, a...

Download a free audiobook version of “The Vanishing Half“ and support TED-Ed's nonprofit mission: https://www.audible.com/ted-ed--While searching for a kidney donor, Karen Keegan stumbled upon a mystery. After undergoing genetic testing, it turned out that some of her cells had a completely different set of genes from the others. And this second set of genes belonged to her twin sister— who had ne...

View full lesson: http://ed.ted.com/lessons/hiv-and-flu-the-vaccine-strategy-seth-berkleySeth Berkley explains how smart advances in vaccine design, production and distribution are bringing us closer than ever to eliminating a host of global threats -- from AIDS to malaria to flu pandemics. Talk by Seth Berkley. Learn more about your ad choices. Visit megaphone.fm/adchoices

Dig into Operation Paperclip, a secret intelligence program which brought scientists from Nazi Germany to the US after WWII.--In May of 1945 the Third Reich was in chaos. Adolf Hitler was dead and German surrender was imminent. But while World War II was almost over, a new war was brewing. And the US was eager to recruit the smartest minds in Germany before the Soviets got the chance— regardless o...

View full lesson: http://ed.ted.com/lessons/the-difference-between-classical-and-operant-conditioning-peggy-andoverWhy is it that humans react to stimuli with certain behaviors? Can behaviors change in response to consequences? Peggy Andover explains how the brain can associate unrelated stimuli and responses, proved by Ivan Pavlov's famous 1890 experiments, and how reinforcement and punishment ca...

Dig into political philosopher John Rawls’ classic thought experiment about what principles we need to design a fair society.--A group of strangers have gathered to design a just society. To ensure none of them rig the system, they’ve been placed under a veil of ignorance. Under this veil, they’re blind to information about age, sex, profession, wealth, religion, and so on. Can they build a fair s...

Scott Fraser studies how humans remember crimes -- and bear witness to them. In this powerful talk, which focuses on a deadly shooting at sunset, he suggests that even close-up eyewitnesses to a crime can create "memories" they could not have seen. Why? Because the brain abhors a vacuum. Editor's note: In the original version of this talk, Scott Fraser misspoke about available footage of Two World...

View full lesson: http://ed.ted.com/lessons/the-importance-of-focus-richard-st-johnHow might focus help you succeed? Using examples of famous people from disparate fields, such as James Cameron, Quincy Jones, and Larry Page, Richard St. John suggests why focus is one of eight traits common in successful people. Lesson by Richard St. John. Learn more about your ad choices. Visit megaphone.fm/adchoi...

Practice more problem-solving at https://brilliant.org/teded--A mathematician with a knife and ball begins slicing and distributing the ball into an infinite number of boxes. She then recombines the parts into five precise sections. Moving and rotating these sections around, she recombines them to form two identical, flawless, and complete copies of the original ball. How is this possible? Jacquel...