TED-Ed

Explore the evolution of English spelling conventions throughout history, and find out why it's such an inconsistent language.--Spelling reformers have been advocating for changes to make English spelling more intuitive and less irregular. One example of its messiness: take the “g-h” sound from “enough,” the “o” sound from “women” and the “t-i” sound from “action,” and you could argue that “g-h-o-...

View full lesson: http://ed.ted.com/lessons/the-simple-but-fascinating-story-of-photosynthesis-and-food-amanda-ootenPhotosynthesis is an essential part of the exchange between humans and plants. Amanda Ooten walks us through the process of photosynthesis, also discussing the relationship between photosynthesis and carbohydrates, starch, and fiber -- and how the air we breathe is related to the foo...

An ancient, abandoned alien space station has been discovered. Can you beat everyone in the galaxy and reach it first?--It’s an incredible discovery: an abandoned alien space station filled with precursor technology. Now every species in the galaxy is in a mad dash to get there first, but you’ve got a problem. Your ship can’t hold enough fuel to get you there unless you vent caches of it into spac...

Discover the world’s largest organism: Pando, an enormous and ancient quaking aspen, and find out how it became so huge.--The largest animal in the world is the blue whale, which weighs a massive 150 metric tons. Even so, it’s not remotely close to being the largest organism by weight. That title goes to an organism so huge that it’s estimated to weigh the equivalent of 40 blue whales. So what is...

View full lesson: http://ed.ted.com/lessons/the-danger-of-science-denial-michael-specterVaccine-autism claims, "Frankenfood" bans, the herbal cure craze: All point to the public's growing fear (and, often, outright denial) of science and reason, says Michael Specter. He warns the trend spells disaster for human progress. Talk by Michael Specter. Learn more about your ad choices. Visit megaphone.fm...

Explore the science behind how gas masks work, and how the technology protects us from airborne threats and pollutants.--You might think of gas masks as clunky military-looking devices. But in the near future, we may need to rely on these filters as part of our everyday lives. In addition to emerging diseases, wildfire frequency has more than tripled, and climate change has increased toxic ground...

Get to know the legend of the king known as Prester John, whose myth would impact the decisions of European leaders for 400 years. --In 1165, copies of a strange letter began to circulate throughout Europe. It spoke of a fantastical realm, containing the Tower of Babel and the Fountain of Youth— all ruled over by the letter’s mysterious author: Prester John. Who was this powerful ruler, and was he...

What gives opals their signature shimmering colors? Dig into the science of the gemstone’s formation, millions of years in the making.--In November 1986, Australian miners climbed Lunatic Hill and bored 20 meters into the Earth. They were rewarded with a fist-sized, record breaking gemstone, which they named the Hailey’s Comet opal. Thanks to a characteristic called “play of color,” no two opals l...

View full lesson: http://ed.ted.com/lessons/how-to-organize-add-and-multiply-matrices-bill-shillitoWhen you're working on a problem with lots of numbers, as in economics, cryptography or 3D graphics, it helps to organize those numbers into a grid, or matrix. Bill Shillito shows us how to work with matrices, with tips for adding, subtracting and multiplying (but not dividing!).Lesson by Bill Shilli...

View full lesson: http://ed.ted.com/lessons/an-athlete-uses-physics-to-shatter-world-records-asaf-bar-yosefWhen 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 physic...

View full lesson: http://ed.ted.com/lessons/why-do-americans-and-canadians-celebrate-labor-day-kenneth-c-davisIn the United States and Canada, the first Monday of September is a federal holiday, Labor Day. Originally celebrated in New York City's Union Square in 1882, Labor Day was organized by unions as a rare day of rest for the overworked during the Industrial Revolution. Kenneth C. Davis illus...

Get to know the story of Shajar Al-Durr, who was born enslaved and rose to become the ruler of Egypt.--The year is 1249 CE. King Louis IX is sailing the Nile, threatening to overthrow the sultan and capture Egypt. Egypt’s commanders ask the sultan’s wife, Shajar Al-Durr, to report this news to the injured sultan. But they don’t know the truth: the sultan is dead, and she is secretly ruling in his...

View full lesson: http://ed.ted.com/lessons/the-business-logic-of-sustainability-ray-andersonAt his carpet company, Ray Anderson has increased sales and doubled profits while turning the traditional "take / make / waste" industrial system on its head. In a gentle, understated way, he shares a powerful vision for sustainable commerce. Talk by Ray Anderson. Learn more about your ad choices. Visit me...

Discover the groundbreaking environmental work of Rachel Carson, whose book “Silent Spring” explores how human actions threaten the balance of nature. --In 1958, after receiving a letter describing the deaths of songbirds due to the pesticide known as DDT, Rachel Carson began an investigation into the misuse of chemicals and their toll on nature. In 1962, she published her findings in “Silent Spri...

Learn about the Greek physician and philosopher Galen of Pergamon, whose experiments and discoveries changed medicine.--In the 16th century, an anatomist named Andreas Vesalius made a shocking discovery: the most famous human anatomy texts in the world were wrong. While Vesalius knew he was right, announcing the errors would mean challenging Galen of Pergamon. Who was this towering figure? And why...

View full lesson: http://ed.ted.com/lessons/the-tribes-we-lead-seth-godinSeth Godin argues the Internet has ended mass marketing and revived a human social unit from the distant past: tribes. Founded on shared ideas and values, tribes give ordinary people the power to lead and make big change. He urges us to do so. Talk by Seth Godin. Learn more about your ad choices. Visit megaphone.fm/adchoices

Dig into the benefits of practicing gratitude in your everyday life, and discover how being thankful can impact your happiness.--Many people would say the connection between happiness and gratefulness is very simple: when you are happy, you are grateful. But think again. Is it really the happy people that are grateful? Quite a number of people have everything that it would take to be happy, and th...

Trace the history of Chinese characters, and find out how this writing system has changed and evolved over thousands of years.--According to legend, in the 27th century BCE, the Yellow Emperor of China charged his historian, Cangjie, to develop a system of writing. Sitting alongside a riverbank, Cangjie noted the imagery that surrounded him. From this, he created the first Chinese characters. So,...

Travel back in time to ancient Mesopotamia and meet Enheduanna, a high priestess and the world’s first author.--4,300 years ago in ancient Sumer, the most powerful person in the city of Ur was banished to wander the vast desert. Her name was Enheduanna, and by the time of her exile, she had written forty-two hymns and three epic poems— and Sumer hadn’t heard the last of her. Who was this woman, an...

View full lesson: http://ed.ted.com/lessons/the-history-of-marriage-alex-gendlerA white, puffy dress. Eternal love. A joint tax return. Marriage means something different to everyone and has changed over time and across cultures. Alex Gendler traces the history of getting hitched, providing insights on polygamy, same-sex unions and even marriage between the dead and the living. Lesson by Alex Gend...

In this accessible talk from TEDxBoston, Richard Resnick shows how cheap and fast genome sequencing is about to turn health care (and insurance, and politics) upside down. (Filmed at TEDxBoston.)Talk by Richard Resnick. Learn more about your ad choices. Visit megaphone.fm/adchoices

What would happen if we could generate power from our windowpanes? In this moving talk, entrepreneur Justin Hall-Tipping shows the materials that could make that possible, and how questioning our notion of 'normal' can lead to extraordinary breakthroughs. Talk by Justin Hall-Tipping. Learn more about your ad choices. Visit megaphone.fm/adchoices

Get to know Pablo Neruda, one of the most celebrated poets of the 20th century and winner of the Nobel Prize in Literature.--A romantic and a revolutionary, Pablo Neruda was one of the most celebrated poets of the 20th century, but also one of the most accessible and controversial. Originally written in Spanish, his poems often use straightforward language and everyday experience to create lasting...

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.) Talk by Bandi Mbubi. Learn more about your ad choices. Visit megaphone.fm/adchoices

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.) Talk...