How do you explain the properties of something we can't see? See how scientists use scientific principles, such as gravity, to observe gases. This lesson explores gases and how we have come to know what we know about them.

Steroids: they're infamous for their use in sports. But they're also found in inhalers, creams to treat poison ivy and eczema, and shots to ease inflammation. The steroids in these medicines aren't the same as those used to build muscle....

Antler cells divide really fast, and with their super-fast growth, antlers resemble tumors in some ways. But animals in the deer family are less likely to get cancer than many other organisms, and a recent genetics study may have...

New technology has revolutionized how we study wild animals, but it has also bogged down scientists with data...luckily, there's an *intelligent* solution.

Having your period is exhausting -- and for many people across the world, menstruation is even more challenging because of stigmas and difficulty getting basic hygiene supplies, says social activist Ananya Grover. In this uplifting,...

This is part 3 of 3 in my series about how our bodies evolved to look like they do.

Language is endlessly variable. Each of us can come up with an infinite number of sentences in our native language, and we're able to do so from an early age— almost as soon as we start to communicate in sentences. How is this possible?...

Trusting your gut may not sound like a reliable way to make decisions, but the research points to some times when you might want to listen to it!

In this video Paul Andersen explains how ecosystems respond to disruptions. Disruptions can cause changes in the number and variety of organisms. It can also lead to migration, extinction or even speciation. Ecosystems that have a...

Not all hardwood trees have hard wood and softwoods soft wood, because these terms denote their taxonomic ancestry, not the wood's actual hardness.

Would mathematics exist if people didn't? Did we create mathematical concepts to help us understand the world around us, or is math the native language of the universe itself? Jeff Dekofsky traces some famous arguments in this ancient...

Given a range of integers from 0 to 100, what would the whole number closest to 2/3 of the average of all numbers guessed be? For example, if the average of all guesses is 60, the correct guess will be 40. The game is played under...

Our moon has no atmosphere, but sometimes it has visible bands of light streaking across its sky, and scientists suspect that electrostatic forces could explain this levitating dust!

In this video Paul Andersen explains how the activation energy is a measure of the amount of energy required for a chemical reaction to occur. Due to the collision theory the activation energy requires proper energy and orientation of...

Today we're going to introduce one of the most flexible statistical tools - the General Linear Model (or GLM). GLMs allow us to create many different models to help describe the world - you see them a lot in science, economics, and...

Today we’ll explore how sociology defines family and the different terms used to describe specific types of family. We’ll look at marriage in different societies, as well as marital residential patterns and patterns of descent. And, of...

Attention isn't just about what we focus on -- it's also about what our brains filter out. By investigating patterns in the brain as people try to focus, computational neuroscientist Mehdi Ordikhani-Seyedlar hopes to build computer...

Doesn't it seem like a lot of online news sites have moved beyond reporting the news to openly inciting your outrage (and your page views)? News analyst Sally Kohn suggests - don't engage with news that looks like it just wants to make...

A quarter of all prescription drugs in the U.S. come from substances that are found only in plants. In this episode of SciShow, we take a look at four of these talented plants who make our lives better.

Today, we're going to begin our discussion of Big Data. Everything from which videos we click (and how long we watch them) on YouTube to our likes on Facebook say a lot about us - and increasingly more and more sophisticated algorithms...

Hank tells us the background story and explains the importance of the science of classifying living things, also known as taxonomy.

Most of the world believed that Earth was the center of the universe for a really long time. Then a few scientists decided to take a closer look.

Many generations have felt they've reached the pinnacle of technological advancement. Yet, if you look back 100 years, the technologies we take for granted today would seem like impossible magic. So - will there be a point where we reach...

Plato and Aristotle: Crash Course History of Science #3