TED-Ed

Wondering how you can catch the perfect wave? Dive into the fascinating and complex physics of surfing. --Whether or not you realize it, surfers are masters of complicated physics. The science of surfing begins as soon as a board first hits the water. Surfers may not be thinking about weather patterns in the Pacific, tectonic geology or fluid mechanics, but the art of catching the perfect wave rel...

Discover the evolutionary purpose of nails, and explore the theories of why they evolved from claws over 55 million years ago. --Consider the claw. Frequently found on animals around the world, it’s one of nature’s most versatile tools. Bears use claws for digging as well as defense. An eagle’s needle-like talons can pierce the skulls of their prey. Even the ancestors of primates used to wield the...

Download a free audiobook version of "The Pillars of the Earth" and support TED-Ed's nonprofit mission: https://www.audible.com/ted-ed Check out our full book recommendation: https://shop.ed.ted.com/collections/ted-ed-book-recommendations/products/illuminati--The year was 1776. In Bavaria, new ideals of rationalism, religious freedom and universal human rights competed with the Catholic church’s h...

Explore the intertwined histories and cultures of the major religions: Hinduism, Judaism, Buddhism, Christianity and Islam.--It's perfectly human to grapple with questions, like 'Where do we come from?' and 'How do I live a life of meaning?' These existential questions are central to the five major world religions -- and that's not all that connects these faiths. John Bellaimey explains the intert...

View full lesson: http://ed.ted.com/lessons/there-s-no-dishonor-in-having-a-disability-steven-claunchWhen faced with a bump in the road, sometimes we forget we have a choice: overcome the obstacle or let it overcome you. Steven Claunch, who was born without fingers on his right hand and with one leg shorter than the other and has excelled in basketball nonetheless, explains why obstacles can provi...

Dig into the Prohibition era in the United States, when the government banned the manufacture, sale, and transport of alcohol. --On January 17, 1920, less than one hour after spirits had become illegal throughout the United States, armed men robbed a Chicago freight train and made off with thousands of dollars worth of whiskey. It was a first taste of the unintended consequences of Prohibition. So...

View full lesson: http://ed.ted.com/lessons/how-bees-help-plants-have-sex-fernanda-s-valdovinosPlants have a hard time finding mates -- their inability to get up and move around tends to inhibit them. Luckily for plants, bees and other pollinator species (including butterflies, moths and birds) help matchmake these lonely plants in exchange for food. Fernanda S. Valdovinos explains how these intri...

Dig into the mystery of Nicolas Bourbaki— one of the most influential mathematicians of all time… who never actually existed.--When Nicolas Bourbaki applied to the American Mathematical Society in the 1950s, he was already one of the most influential mathematicians of his time. He’d published articles in international journals and his textbooks were required reading. Yet his application was firmly...

View full lesson: http://ed.ted.com/lessons/defining-cyberwarfare-in-hopes-of-preventing-it-daniel-garrieCan you imagine a future where wars are fought not with bombs and bullets but computer viruses and pacemaker shutdowns? Cyberware is unique in that it is not covered by existing legal framework and it often inspires more questions than we are yet capable of answering. Daniel Garrie ponders some...

Get to know the science behind what causes the stiff, creaky joints of the most common forms of arthritis and what you can do to prevent it. --The bad backs, elbow pain, and creaky knees so common in older people often aren't just “old age.” In fact, the source of this stiffness plagues many young people as well. The culprit is arthritis: a condition that affects over 90 million people in the U.S....

Learn about the life and tragic death of gay rights pioneer Harvey Milk, California’s first openly gay public official.--By 1973, Harvey Milk had already been many things: naval officer, high school teacher, bit-part actor and wandering hippie. Starting fresh in San Francisco, his belief in a more personal approach to local government led him to run for office in the heart of American gay culture,...

Dig into Noam Chomsky’s theory of universal grammar and decide: are there universal grammar rules and are they hardwired into our brains?--Language is endlessly variable. Each of us can come up with an infinite number of sentences in our native language, and we’re able to do so from an early age— almost as soon as we start to communicate in sentences. How is this possible? In the early 1950s, Noam...

View full lesson: http://ed.ted.com/lessons/the-walk-from-no-to-yes-william-ury William Ury, author of "Getting to Yes," offers an elegant, simple (but not easy) way to create agreement in even the most difficult situations -- from family conflict to, perhaps, the Middle East. (Filmed at TEDxMidWest.) Talk by William Ury. Learn more about your ad choices. Visit megaphone.fm/adchoices

View full lesson: http://ed.ted.com/lessons/the-chemistry-of-cookies-stephanie-warrenYou stick cookie dough into an oven, and magically, you get a plate of warm, gooey cookies. Except it's not magic; it's science. Stephanie Warren explains via basic chemistry principles how the dough spreads out, at what temperature we can kill salmonella, and why that intoxicating smell wafting from your oven ind...

View full lesson: http://ed.ted.com/lessons/mysteries-of-vernacular-lady-jessica-oreck-and-rachael-teelWhy do we call women ladies? Well, etymologically-speaking, the word comes from the Old English words for hlaf (bread) and daege (maid), which, combined, mean the female head of the household and eventually indicated high social standing. Jessica Oreck and Rachael Teel follow the word to its cont...

View full lesson: http://ed.ted.com/lessons/all-of-the-energy-in-the-universe-is-george-zaidan-and-charles-mortonThe energy in the universe never increases or decreases -- but it does move around a lot. Energy can be potential (like a stretched-out rubber band waiting to snap) or kinetic (like the molecules that vibrate within any substance). And though we can't exactly see it, every time we cook...

View full lesson: http://ed.ted.com/lessons/a-brief-history-of-religion-in-art-ted-edBefore we began putting art into museums, art mostly served as the visual counterpart to religious stories. Are these theological paintings, sculptures, textiles and illuminations from centuries ago still relevant to us? Jeremiah Dickey describes the evolution of art in the public eye and explains how the modern v...

Get to know the story of Quanah Parker, a Native American warrior and leader, and the last chief of the Comanche tribe. --Late one night in 1871, a group of riders descended on a sleeping army camp, stole about 70 horses, and disappeared. Led by a young chief named Quanah Parker, the raid was the latest in a long series of altercations along the Texas frontier between indigenous people and United...

View full lesson: http://ed.ted.com/lessons/the-arctic-vs-the-antarctic-camille-seamanHow can you tell the two poles apart? Where are the penguins? What about the bears? The Arctic pole is located in the Northern Hemisphere within the deep Arctic Ocean, while the Antarctic pole is smack in the middle of the ice-covered Antarctica. Camille Seaman describes how enterprising people and organisms have...

What makes a tree grow tall? And do trees ever stop growing? Explore how photosynthesis and gravity can affect and limit the height of trees. --Reaching heights of over 100 meters, Californian sequoias tower over Earth’s other 60,000 tree species. But even these behemoths seem to have their limits: no sequoia on record has been able to grow taller than 130 meters. So what exactly is stopping these...

Dive into the Taino myth of the sea, and watch as Deminan and his brothers accidentally create a new world from a giant gourd. --Before the world of humans began, there was the world of the gods. Four brothers wandered this celestial realm. One day, the brothers snuck into a spirit’s house and spotted a giant gourd hanging in the corner. But as they tried to look inside the gourd, they dropped it....

Dig into the science of how new volcanoes form, and what causes their unpredictable eruptions. --In February of 1942, Mexican farmer Dionisio Pulido thought he heard thunder coming from his cornfield. However, the sound wasn’t coming from the sky. The source was a large, smoking crack emitting gas and ejecting rocks, and would come to be known as the volcano Paricutin. Where do new volcanoes like...

Discover how evolution and natural selection influence why the human body has vestigial organs— body parts that no longer serve their original purpose. --You know that little pink thing nestled in the corner of your eye? It’s actually the remnant of a third eyelid. In humans, it’s vestigial, meaning it no longer serves its original purpose. There are several other vestigial structures in the human...

View full lesson: http://ed.ted.com/lessons/tycho-brahe-the-scandalous-astronomer-dan-wenkelIf you think scientists lead boring, monotonous lives, you must not know about Tycho Brahe. The 16th century astronomer who accurately predicted planetary motion led quite a dramatic life -- complete with a kidnapping, a sword duel and even a clairvoyant dwarf. Dan Wenkel dives into the history behind this...

Discover the tale of the lovestruck boy sent into Hell to steal 3 hairs from the Devil to appease his true love's father, the king.--In a small town, a proud mother showed off her newborn son. Upon noticing his lucky birthmark, townsfolk predicted he would marry a princess. But soon, these rumors reached the wicked king. Enraged, the king stole the child away, and sent him hurtling down the river....