Models are great, except they're also usually inaccurate. In this episode of Crash Course Chemistry, Hank discusses why we need models in the world and how we can learn from them... even when they're almost completely wrong. Plus, Lewis...

We have learned over the past few weeks that gases have real-life constraints on how they move here in the non-ideal world. As with most things in chemistry (and also in life) how a gas moves is more complex than it at first appears. In...

Enslaved people resisted their condition in a range of different ways. Oftentimes those ways were small and personal. There were also times when that resistance took on larger, more dramatic forms, like with slave uprisings and...

We’ve all heard the phrase “opposites attract.” It may or may not be true for people, but it’s definitely true in organic chemistry. In this episode of Crash Course Organic Chemistry, we’re learning about electronegativity, polarity,...

Hank lets us in on the meaning of life, at least from a biological perspective - it's reproduction, which answers the essential question of all organisms: how do I make more of myself? So, sex, how does it work?

We may be living IN a simulation (according to Elon Musk and many others), but that doesn't mean we don't need to perform simulations ourselves. Today, we're going to talk about good experimental design and how we can create controlled...

As cinema started to take off, things like "single viewer" devices weren't going to cut it as the medium advanced. In this episode of Crash Course Film History, Craig talks to us about the Lumiere brothers, their invention of the...

Today Hank explains your unsung lymphatic system and how it supports cardiovascular function by collecting, filtering, and returning interstitial fluid back into the bloodstream via a system of lymphatic vessels. He also explains the...

Today we’re going to create memory! Using the basic logic gates we discussed in episode 3 we can build a circuit that stores a single bit of information, and then through some clever scaling (and of course many new levels of abstraction)...

A unit is the frequently arbitrary designation we have given to something to convey a definite magnitude of a physical quantity and every quantity can be expressed in terms of the seven base units that are contained in the international...

One way of thinking about family life says that there are stages that families move through: courtship, marriage, child-rearing, and family life in your later years. We’ll also discuss changing patterns of marriage and childbearing in...

If you’ve been paying attention so far in this series, you’ve probably heard of benzene. This molecule is flat, cyclic, and belongs to a special class of compounds known as aromatics. In this episode of Crash Course Organic Chemistry,...

In which we continue our exhaustive look at One Hundred Years of Solitude by Gabriel Garcia Marquez.

In which John Green teaches you about a time of relative tumult in the United States, the 1960s. America was changing rapidly in the 1960s, and rights movements were at the forefront of those changes. Civil Rights were dominant, but the...

In the previous episode we discussed what happens when we use electrophilic aromatic substitution to add a group to a benzene ring, but what happens when you try to add even more groups? Well, things get a little more complicated. In...

What is a monopoly? It turns out, it's more than just a board game. It's a terrible, terrible economic practice in which giant corporations dominate markets and hurt consumers. Except when it isn't. In some industries, monopolies are the...

Barack Obama was the first Black man elected President in the United States in 2008. In this episode, Clint Smith will explore the early life, political career, presidential campaign, and legislative milestones of Barack Obama.

Today we are talking about the life -- and death -- of stars. Low mass stars live a long time, fusing all their hydrogen into helium over a trillion years. More massive stars like the Sun live shorter lives. They fuse hydrogen into...

So, electric current works like a river... kinda... Instead of flowing based on elevation, electric current works a little differently. But it's a good metaphor. In this episode of Crash Course Physics, Shini talks to us about electric...

This week we build on our naked eye observations from last week and take a look at the cyclical phenomena that we can see at work in the universe.

Continuing in our journey of understanding motion, direction, and velocity... today, Shini introduces the ideas of Vectors and Scalars so we can better understand how to figure out motion in 2 Dimensions. But what does that have to do...

Hank describes how cells regulate their contents and communicate with one another via mechanisms within the cell membrane.

How do we design the most efficient machines and processes? Today we’ll try to figure that out as we discuss heat & work, reversibility & irreversibility, and how to use efficiency to measure a system.

In fantasy stories, charlatans in fancy robes promise to turn lead into gold. But real alchemists weren’t just mystical misers. They were skilled experimentalists, backed by theories of matter. And they played a huge role in the...