How Stuff Works  |  Podcast, ±3 min episodes every 2 days
Join Marshall Brain in the BrainStuff Podcast and learn answers to life's everyday questions. Improve your knowledge with the BrainStuff Podcast.

How does Nitroglycerin work?

What do you get when you combine acids and glycerin? Nitroglycerin! What is this substance used for, and why is it so unstable? In this episode, Marshall takes a look at the chemistry and explosive qualities of Nitrogyclerin.

What is chewing gum made of?

Up until World War II, chewing gum was made of a substance called chicle. Check out this HowStuffWorks podcast to learn more about the ingredients of modern chewing gum.

Why can't a couch potato run a marathon?

Intuitively, it makes sense that a trained athlete can run a marathon easily, while a "couch potato" can barely run a mile. But what's the biology behind it? Find out how fit and unfit bodies respond to exercise in this episode.

Why doesn't paper money disintegrate in the washing machine?

Normal paper is made of cellulose from trees, but paper money is made from cotton and linen fibers. Learn how this makes paper money more water-resistant in this podcast from HowStuffWorks.

How do polymer crystals work, and why do they absorb so much water?

Polymer crystals are extremely absorbent, and that's why you'll often find them in disposable diapers. Marshall explains how polymer crystals are able to absorb large quantities of liquids -- and keep you cool and dry -- in this episode.

How do people pull large objects with their teeth?

Have you ever seen those folks that can pull a whole truck with their teeth? Tune in as Marshall Brain explains the physics behind pulling large objects with your teeth in this episode.

Why is a popsicle called a quiescently frozen confection?

Popsicles are also called "quiescently frozen confections" because of the way they're frozen. Learn more about how flavored ice treats are made -- and what distinguishes them from ice cream -- in this episode.

How do scratch-and-sniff stickers work?

Scratch-and-sniff stickers are novelties that delight both children and adults. Sniff out the ingenious technology that makes them work in this podcast from

Why is carbon monoxide so poisonous?

The structure of hemoglobin causes oxygen to bind loosely to iron -- however, carbon monoxide binds very tightly to the blood's iron, reducing your ability to breathe. Check out this podcast from HowStuffWorks to learn more.

How do I know if my catalytic converter has failed?

An automobile's catalytic converter uses a catalyst to convert harmful exhaust fumes into harmless ones. Find out what happens when your catalytic converter stops working properly -- and how you can tell -- in this episode.

What is the worst invasive public species?

From kudzu to cane toads, invasive species are changing the world. But which of these transplants is the worst for the local landscape? Tune in as Marshall Brain tackles invasive species across the world -- and ultimately concludes which one is the worst.

How many people work at a Formula 1 pit stop?

If you've ever seen a Formula 1 race, then you know the race isn't just between cars -- it's also between pit stop crews. In seven seconds these crews perform an entire pit stop. But how does it work, and how many people does it take? Tune in to find out.