In which John Green teaches you about the Holy Roman Empire by teaching you about Charles V. Charles Hapsburg was the holy Roman Emperor, but he was also the King of Spain. And the King of Germany. And the King of Italy and the Lord of...

In which John Green teaches you about Imperialism, but not from the perspective of the colonizers. This week John looks at some Asian perspectives on Imperialism, specifically writers from countries that were colonized by European...

In which John Green teaches you about water! So, we talk about resources a lot on Crash Course, and today is no exception. It turns out people can't live without water, which means it's absolutely necessary for civilization. Today John...

In which John Green talks about the methods of writing history by looking at some of the ways that history has been written about the rise of the West. But first he has to tell you what the West is. And then he has to explain the Rise of...

In which John Green teaches you about how Islam has interacted with politics during it's history, and how it continues to do so today. Islamist movements are in the news a lot lately, but how did that happen. John will point out that...

“In the future, companies will succeed or fail based on how much their people enjoy their work,” says management consultant Rosie Sargeant. She offers three tips to make work more joyful, increase employee retention and boost customer...

Rosalind Franklin was a British scientist who helped discover the structure of DNA, but you most likely haven't heard of her. Hank will attempt to fix this gap in your knowledge on today's SciShow: Great Minds

In a viral story, one researcher claims to be able to double the lifespan of our feline friends by curing chronic kidney disease. We don't know if he can make cats live twice as long, but we do know the science - and the upcoming...

Perhaps for plants in times of great stress and ecological upheaval, the more DNA the better.

From diabetes to Alzheimer's, there's a lot that we hope to be able to treat using stem cell therapies. But the stem cells we use tend to be hard to come by. But it turns out there's a new source of stem cells that has researchers...

We often think of the ocean’s tide as a simple rise and fall, connected to the motion of the Moon. But on any given shore, the reality is much more complex and oceanic scientists have realized recently that there’s another, more...

You might have a friend who is “double-jointed" and can bend their fingers in freaky ways. Why are they are so flexible?

I don't mean it mean, but today we're going to be cruel. It's the fun-loving Theater of Cruelty, which was pioneered by the genius Antonin Artaud in France during the inter-war period in twentieth century. The Theater of Cruelty was...

This video is about the Schwarzschild radius of a black hole, (its "event horizon"), and how much mass and density is required to reach the point of no return where an object like a star, neutron star, red giant, etc...

Physicist Geoffrey West has found that simple, mathematical laws govern the properties of cities -- that wealth, crime rate, walking speed and many other aspects of a city can be deduced from a single number: the city's population. In...

In this energizing talk, Amory Lovins lays out his simple plan for weaning the US off oil and revitalizing the economy.

Your boss probably isn't paying you what you're worth -- instead, they're paying you what they think you're worth. Take the time to learn how to shape their thinking. Pricing consultant Casey Brown shares helpful stories and learnings...

After months of travel, you've arrived at Duonia, home to the famous temple that's the destination of your pilgrimage. The walk from the welcome center to the temple isn't a long one ... but there's a problem. Can you outsmart the city's...

Modern work -- from waiting tables to crunching numbers to designing products -- is about solving brand-new problems every day, flexibly and collaboratively. But as Yves Morieux shows in this insightful talk, too often, an overload of...

Say the word "doubt" aloud. What is that "b" doing there? Does it have any purpose? Gina Cooke explains the long and winding history of "doubt" and why the spelling, though it seems random, is a wink to its storied past.

If you dream of becoming an astronaut, the selection process and the job are both pretty grueling. For several reasons, you'd better practice your handshake.

DNA isn’t the simple, loose double-helix you might see in a biology textbook, so isolating single strands of it can be next to impossible. But with some simple tricks of physics, scientists came up with a special type of tweezers that...

Rosalind Franklin was a British scientist who helped discover the structure of DNA, but you most likely haven't heard of her. Hank will attempt to fix this gap in your knowledge on today's SciShow: Great Minds.

We often think of the ocean’s tide as a simple rise and fall, connected to the motion of the Moon. But on any given shore, the reality is much more complex and oceanic scientists have realized recently that there’s another, more...