Nowadays, we're pretty confident about how the dinosaurs died out, but there are still other extinctions throughout Earth's history, some big, some small, that remain unsolved.

Why do your fingers and toes get wrinkly when they’ve been in the water too long? Short answer: Your nerves. Longer answer: Evolution.

About 10% of the world population is left-handed. But why does handedness exist and what determines which hand is dominant? Scientists have suggested several theories, but the answer may well lie with evolution.

In the early 20th century, Alfred Wegener's theory of Continental Drift laid the foundation for our modern theory of plate tectonics. And today we know something even more exciting: Pangea was only the latest in a long lineage of...

Book: Einstein

What is a vector space? Even though they are initial taught in the context of arrows in space, or with vectors being lists of numbers, the idea is much more general and far-reaching.

Some see string theory as the one great hope for a theory of everything - that it will unite quantum mechanics and gravity and so unify all of physics into one glorious theory.

What is a vector space? Even though they are initial taught in the context of arrows in space, or with vectors being lists of numbers, the idea is much more general and far-reaching.

Paul Andersen explains how scientists modify theories by constructing explanations. He also discusses the cycle of design used by engineers to solve problems. He starts by defining a theory as a well-established explanation of a...

Between them, general relativity and quantum mechanics seem to describe all of observable reality.

In which John Green teaches you about nation building and nationalism in Latin America. Sometimes, the nations of Latin America get compared to the nations of Europe, and are found wanting. This is kind of a silly comparison. The rise of...

Paul Dirac's insights into the nature of Quantum Mechanics laid the foundation for Quantum Field Theory and predicted the existence of anti-matter. Part 1 in our series on Quantum Field Theory.

It's the most famous prediction of perhaps the most famous genius of our time ... Stephen Hawking's theory of Hawking Radiation.

Armed with a sense of humor and laypeople's terms, Nobel winner Murray Gell-Mann drops some knowledge on TEDsters about particle physics, asking questions like, Are elegant equations more likely to be right than inelegant ones?

Isaac Newton's Universal Law of Gravitation tells us that there is a singularity to be found within a black hole, but scientists and mathematicians have found a number of issues with Newton's equations. They don't always accurately...

SciShow Space describes a new phenomenon that might be out there: Stars made entirely out of metal. But it's not quite what it sounds like!

In just the last century, we've made an astounding amount of scientific progress. And thanks to some of that progress, we can now share 10 of those discoveries with you in a video on the internet!

Physicists are interested in the big questions like "Where did we come from?" and "What is all this stuff?". But the answers to some of these questions, just lead to more questions.

Some people try to attack things like evolution by natural selection and man-made climate change by saying "Oh, that's just a THEORY!" Yes, they are both theories. Stop saying it like it's a bad thing! It's time we learn the difference...

In which Hank and John Green teach you about life on Earth. They won't be giving advice on how life should be lived, because this is a history series. Instead, they'll teach you about the earliest forms of life on Earth, and some of the...

Does science tell us that Tylenol is changing our personalities? The short answer is 'no'. And learn about advances in transportation technology in this SciShow news.

Physicist Brian Greene explains superstring theory, the idea that minscule strands of energy vibrating in 11 dimensions create every particle and force in the universe.

About 10% of the world population is left-handed. But why does handedness exist and what determines which hand is dominant? Scientists have suggested several theories, but the answer may well lie with evolution.

We begin our unit on ethics with a look at metaethics. Hank explains three forms of moral realism – moral absolutism, and cultural relativism, including the difference between descriptive and normative cultural relativism – and moral...