Today, we’re going to take a look at how the government plays a role in the economy. Specifically, the way the government creates and maintains our market economic system. Now sure, the government’s role in the economy can be...

There are three types of color receptors in your eye: red, green and blue. But how do we see the amazing kaleidoscope of other colors that make up our world? Colm Kelleher explains how humans can see everything from auburn to aquamarine.

In this revelatory talk, technologist Kayvon Tehranian explores why NFTs -- digital assets that represent a certificate of ownership on the internet -- are a technological breakthrough. Learn how NFTs are putting power and economic...

The earliest time measurements were observations of cycles of the natural world, using patterns of changes from day to night and season to season to build calendars. More precise time-keeping eventually came along to put time in more...

A 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,...

A beautiful proof of why slicing a cone gives an ellipse.

The universe is huge and getting bigger all the time, and we have we have dark energy - the most mysterious force in the universe - to blame/thank for it. Thought to make up more than 70% of the energy in the whole universe, Hank...

The Universe is expanding which means distant galaxies are only moving farther away from us. So in the farthest future, will our night sky be empty?

Drawing curves that fill all of space, and a philosophical take on why mathematics about infinite objects can still be useful in finite contexts.

Quick, think of three words to describe yourself. TIME'S UP! What did you think of? Chances are you thought of descriptive words that we call Properties. In this episode of Crash Course Kids, Sabrina talks about how properties help us...

How do you think about the column space and null space of a matrix visually? How do you think about the inverse of a matrix?

Why are most manhole covers round? Sure it makes them easy to roll, and slide into place in any alignment. But there's another, more compelling reason, involving a peculiar geometric property of circles and other shapes. Marc Chamberland...

In this short, optimistic talk from TED2009, Pete Alcorn shares a vision of the world of two centuries from now -- when declining populations and growing opportunity prove Malthus was wrong.

The shape, contents and future of the universe are all intricately related. We know that it's mostly flat; we know that it's made up of baryonic matter (like stars and planets), but mostly dark matter and dark energy; and we know that...

Multidisciplinary artist and TED Fellow Paul Rucker is unstitching the legacy of systemic racism in the United States. A collector of artifacts connected to the history of slavery -- from branding irons and shackles to postcards...

A beautiful proof of why slicing a cone gives an ellipse.

Daily, Americans exercise their rights secured by the Constitution. The most widely discussed and debated part of the Constitution is known as the Bill of Rights. Belinda Stutzman provides a refresher course on exactly what the first ten...

When you think of surfactants, you might think of soaps, detergents and other man-made chemicals. But it turns out that some other animals utilize their own versions of these sudsy molecules.

A beautiful proof of why slicing a cone gives an ellipse.

If Fermat had a little more room in his margin, what proof would he have written there?

It's 1762 BCE. As dawn breaks in the Babylonian city of Sippar, Beltani— a priestess and businesswoman— receives an urgent visit from her brother. He makes a troubling accusation: her tavern keeper has been undermining the business...

Humans have an almost insatiable energy demand, so scientists and engineers are always on the lookout for sustainable ways to provide the energy we need. And some of these ideas go way beyond solar panels and wind...

We try not to get into too much great man history here at Crash Course, but we have to admit: Napoleon Bonaparte is a pretty big deal. Join us as we track the rise, further rise, fall, rise, fall, mortal fall, and posthumous rise of...

In which John Green teaches you about the American Revolution. And the Revolutionary War. I know we've labored the point here, but they weren't the same thing. In any case, John will teach you about the major battles of the war, and...