With help from some surprising footage, Derek Sivers explains how movements really get started. (Hint: it takes two.)

You've heard of E=mc2... but you probably haven't heard the whole story.

Chinese alchemists searching for an elixir of eternal life discovered the world's first chemical explosive. Hank has the full story on gunpowder in this SciShow about a big idea of science.

What if, no matter how strong your password was, a hacker could crack it just as easily as you can type it? In fact, what if all sorts of puzzles we thought were hard turned out to be easy? Mathematicians call this problem P vs. NP, it...

In this video Paul Andersen explains how matter can act as a wave at the nanoscale. Louis de Broglie showed that the wavelength of matter can be calculated using the momentum of an object and Planck's constant. The Davisson-Germer...

In this video Paul Andersen explains how the gravitational mass is a measure of the force on an object in a gravitational field. The gravitational mass is based on the amount of material in an object and can be measured to a standard kg...

In this video Paul Andersen explains how an object with mass placed in a gravitational field experiences a gravitational force. On the Earth this gravitational force is known as weight. The gravitational force is equal to the product...

A visual for derivatives which generalizes more nicely to topics beyond calculus. Thinking of a function as a transformation, the derivative measure how much that function locally stretches or squishes a given region.

An algorithm is a method of solving problems both big and small. Though computers run algorithms constantly, humans can also solve problems with algorithms. David J. Malan explains how algorithms can be used in seemingly simple...

With his signature resolve, former US President Jimmy Carter dives into three unexpected reasons why the mistreatment of women and girls continues in so many manifestations in so many parts of the world, both developed and developing....

In this video Paul Andersen explains how thermodynamic and equilibrium reasoning can be related through changes in free energy and the equilibrium constant. When the delta G is negative the reaction shifts to the right or favors...

Hank describes how non-Newtonian fluids can save lives - and dreams of a bulletproof hoodie.

In this video Paul Andersen explains how the linear momentum is equal to the product of the mass of an object and the velocity of the center of mass. He uses video analysis software to calculate the velocity of an object and therefore...

Pianos can't be perfectly tuned - it's a mathematical fact!

Picture this: you're gorging on leftover Halloween candy. You take a bite of a fun-size chocolate bar and instead of sugary goodness, you get a flash of blinding pain in your tooth! What's the deal?

A visual for derivatives which generalizes more nicely to topics beyond calculus.

What happens when you jump in a moving elevator? Do you weigh more when you're going up and less when you're going down? Carol Hedden explores the relationship between gravity, weight, and relative motion, using a moving elevator to...

In this video Paul Andersen explains how buffer solutions maintain pH in a solution. A buffer solution is made up of a weak acid and its conjugate base. As strong acids or bases are added the pH remains stable. A good buffer solution...

Psyche was born so beautiful that she was worshipped as a new incarnation of Venus, the goddess of love. But human lovers were too intimidated to approach her, and Apollo recommended her father abandon her on a crag where she would marry...

Today we are taking all the things we have learned this year about doing philosophy and applying that to moral considerations regarding non-human animals. We’ll explore what philosophers like Peter Singer and Carl Cohen have to say about...

How to think about implicit differentiation in terms of functions with multiple inputs, and tiny nudges to those inputs.

Understanding gravity can sometimes be a bit of a balancing act, much like the fundamental laws of physics and how they inform what it is exactly that Earth orbits.

Cotton is everywhere in our modern world, and it became a hugely important crop in the 19th century United States. Cotton was a huge economic boon to the US, and much of that wealth was built on the backs of enslaved laborers. And...

In this video Paul Andersen explains how light travels in photons which can be described as both particles and waves. Einstein showed that photons can be described as particles using the photoelectric effect to show that the energy of a...