In which John Green teaches you about disease and the effects that disease has had in human history. Disease has been with man since the beginning, and it has shaped the way humans operate in a lot of ways. John will teach you about the Black Death, the Great Dying, and the modern medical revolution that has changed the world.

How do astronomers make sense of the vastness of space? How do they study things so far away? Today Phil talks about distances, going back to early astronomy. Ancient Greeks were able to find the size of the Earth and from that the distance to and the sizes of the Moon and Sun. Once the Earth/Sun distance was found, parallax was used to find the distance to nearby stars, and that was bootstrapped using brightness to determine the distances to much farther stars.

Chapters:
Introduction
How did we calculate the Earth's Size?
THE Astronomical Unit (AU) = 149,597,870.7 km
Depth Perception & Parallax
Light Years & Parsecs
Brightness Indicates Distance
Review

Even though animals can look very different on their surface, there are surprising similarities in how they’ve evolved to solve major problems - like how to support and move their bodies. Today, we’ll take a look at the various ways animals can grow, learn how and why some animals evolved to have a head and others evolved to not have a head, and examine the different types of skeletons - from those inside bodies (like our own), to skeletons outside bodies (like in insects), and even those made of water (like in jellyfish). Evolution is a wild journey that brings us so many different animals with a huge array of bodies and sizes - that is, until everything turns into a crab!

As we venture into the world of ethics, there are a lot of different answers to the grounding problem for us to explore. One of the oldest and most popular is the divine command theory. But with age comes a long history of questions, too, such as the dilemma presented by Plato known as the Euthyphro Problem.

Art is the perfect tool for activists to get across their message and make people pay attention. In this episode of Crash Course Art History, we’ll learn about the centuries-long practice of iconoclasm, how art intersects with protest movements, and what happens to artists when the authorities aren’t thrilled by their acts of resistance.
Chapters:
Introduction: Gran Fury & ACT-UP
Performance Art
Jaune Quick-to-See Smith
Ai Weiwei
Iconoclasm
Review & Credits
Credits

In which Hank blows our minds with the different kinds of solids out there and talks about why they're all different and have different properties. Today, you'll learn about amorphous and crystalline solids, types of crystalline solids, types of crystalline atomic solids, properties of each type of solid, and that the properties depend on the bond types.

In which John Green teaches you a little bit about drought, which is a natural weather phenomenon, and famine, which is almost always the result of human activity. Throughout human history, when food shortages strike humanity, there was food around. There was just a failure to connect those people with the food that would keep them alive. There are a lot of reasons that food distribution breaks down, and John is going to teach you about them in the context of the late-19th century famines that struck British India.

Today we’re talking about mass transfer. It doesn’t just apply to objects and fluids as a whole, but also to the individual molecules and components that make them up. We’ll see that transfers of mass need their own driving force, discuss diffusion, and use Fick’s Law to help us model mass transfer.

We’re continuing our exploration of conflict theories with W.E.B. Dubois, who is one of the founders of sociological thought more broadly and the founder of race-conflict theory. We’ll discuss shifting ideas about race, Dubois’ idea of ‘double-consciousness’, and the modern day field of racial identity. We’ll explore the idea racial formation and discuss Dubois’ survey of African Americans in Philadelphia to look at how economic, political, and social structures affect how we perceive different races – and vice versa. We’ll also discuss the activist side of Dubois’ life as co-founder of the NAACP and editor of the Crisis, and how modern day sociologists study racial politics and racial resistance.

This week Craig is going to continue our discussion of due process. Technically, we started last week with the 4th amendment and search and seizure, but this week we’re going to look at the 5th and 6th amendments and how they ensure a fair trial. We’ll talk about some stuff you tend to hear a lot on tv, like your right to an attorney and a jury of your peers and also terms like “double jeopardy” and “pleading the fifth”. Now, this stuff can get pretty complicated, which is where lawyers come in handy, but it’s important to know your liberties to keep the police and other judicial officers in check.

While the English were falling apart a little, with their civil war and their restoration and their succession problems, the Dutch were getting their act together. They were throwing off the yoke of the Spanish Empire, uniting their provinces, and building out their global trade network. Today, we'll learn about how the Dutch came to their Golden Age, and how it ended.

This week on Crash Course World Mythology, it's the Circle of Life. And Death. And sometimes, Life again. Mike Rugnetta is teaching you about Dying Gods, by which I mean gods that die, and then return to life. You'll learn about the Corn Mother from Native American Traditions, Adonis of the Greek and Roman pantheon, Odin of the Norse, and a little about the most famous dying deity, Jesus. These aren't all the dying gods in the world, but it's a good introduction to the archetype.

We’ve spent the last few episodes talking about substitution reactions, but now it’s time to talk about a related type of reaction: elimination reactions! Elimination reactions are super important because they are the main way we can make compounds with double and triple bonds in organic chemistry. In this episode of Crash Course Organic Chemistry we’re going to cover… a lot, including a review of substitution reactions, E1 and E2 mechanisms, Zaitsev’s rule, and more. And of course, we’ll finish with some practice problems.

Alkenes are an important type of molecule in organic chemistry that we’re going to see a lot more of in this series. But before we can really get into the many cool reactions alkenes do, we need to go over some of the basics. In this episode of Crash Course Organic Chemistry, we’ll review and build on our knowledge of alkene nomenclature, revisit our friend the carbocation, and learn Markovnikov’s Rule: an important tool that will help us predict the products of addition reactions involving alkenes.

During our Film History and Production series, we talked about how Film is an "Illusion of Reality." That filmmakers use shots, cuts, and narrative structure to trick us into believing what we're seeing. But, what happens when that Illusion of Reality is an Illusion of Actual Reality? Otto Bell's "The Eagle Huntress" is a feel good, enchanting, and powerful hero's journey. But its characters are real. It's a documentary. And, as good as the film is, it's not without appropriate criticisms. In this episode of Crash Course Film Criticism, we take a look at a documentary that's as moving as any narrative fiction film.

Hello, world! Welcome to Crash Course Computer Science! So today, we’re going to take a look at computing’s origins, because even though our digital computers are relatively new, the need for computation is not. Since the start of civilization itself, humans have had an increasing need for special devices to help manage laborious tasks, and as the scale of society continued to grow, these computational devices began to play a crucial role in amplifying our mental abilities. From the abacus and astrolabe to the difference engine and tabulating machine, we’ve come a long way to satisfying this increasing need, and in the process completely transformed commerce, government, and daily life.

Since Joseph Marie Jacquard’s textile loom in 1801, there has been a demonstrated need to give our machines instructions. In the last few episodes, our instructions were already in our computer’s memory, but we need to talk about how they got there - this is the heart of programming. Today, we’re going to look at the history of programming and the innovations that brought us from punch cards and punch paper tape to plugboards and consoles of switches. These technologies will bring us to the mid 1970s and the start of home computing, but they had limitations, and what was really needed was an easier and more accessible way to write programs - programming languages. Which we’ll get to next week.

Phil starts the planet-by-planet tour of the solar system right here at home, Earth.

Chapters:
Introduction: The Earth
Layers of Earth
Continental Plates
Why is the Earth's Core so Hot?
Earth's Magnetic Field
Earth's Atmosphere
Atmospheric Pressure
Liquid Water on Earth
The Greenhouse Effect: CO2 in the Atmosphere
Review

So, we’re still talking about sex this week, but we’re talking about Earth Mothers and their children. We'll start with Gaia, and her son Kronos, who had a classic childhood rebellion, and castrated his father. We'll also get into Kronos’s son Zeus, who would go on to dethrone his father. We’ll talk about Norse mythology, too, and look at the family that created the world, and worked together to make people.

It's Earth Science time!!!! In this field, natural philosophers were asking questions like, what’s up with fossils? Are they the remains of extinct organisms? Or are they so-called “sports of nature”—rocks that just happen to look like living things but don’t /mean/ anything? And most importantly, how old is… everything?