Brainstuff

Today's pencils are manufactured very differently than the original versions; but they still use a material called graphite, which isn't lead at all. How does the graphite get in the pencil? Find out in this episode. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

Once relegated to high-end restaurants and clubs, valets are increasingly common across the United States. But how can you trust your valet -- and how will you know if the valet is scamming you? Tune in and find out. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

As a method of treating cancer, proton therapy has great potential. But how does it work, exactly, and what makes it superior to other forms of cancer treatment? Tune in and find out. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

A lightyear is a way of measuring distance -- specifically, the distance light can travel in one year. Just how far is that? Check out this podcast from HowStuffWorks to learn more about astronomy. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

The average adult at rest inhales and exhales between 7 to 8 liters of air each minutes. Check out this HowStuffWorks podcast to learn how much oxygen a person uses during a day of inhalation and exhalation. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

When you buy a gallon of bleach at the grocery store, what are you actually purchasing? Check out this HowStuffWorks podcast to learn more about bleach, chlorine and the chemical reactions behind these products. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

Water is made up of hydrogen and oxygen, so why aren't we able to breathe underwater? Find out in this episode of BrainStuff. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

A camshaft plays an integral role in the functioning of an engine. And dual overhead cams ramp up a machine's performance even more. Find out how dual overhead camshafts work in this episode. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

By using a computer to monitor the rotation of the car's wheels, an anti-lock braking system helps drivers avoid skids. Could this computer also monitor flat tires? Check out this HowStuffWorks podcast to learn more about brake systems. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

Across the country, incandescent traffic lights are being replaced with LED arrays. Check out this podcast from HowStuffWorks to learn more about the advantages of LED traffic lights. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

Circular saws are much noisier than table saws partly because of the type of motor they possess. Learn more about universal and induction motors in BrainStuff, a podcast from HowStuffWorks.com. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

Airplane toilets serve the same function as regular ones, but because they exist in a moving environment, they rely on slightly different technology to get the job done. Find out how they work in this podcast from HowStuffWorks.com. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

Cats tend to purr when they're happy, but pleasure isn't the only reason for this behavior. And they aren't the only animals who purr. Find out why and how cats and other animals purr in this episode of BrainStuff. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

Learn about the causes of gas -- and not the kind you put in your car -- in this podcast from Marshall Brain. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

Milk is often touted as a "miracle drink," full of restorative, nutritional properties. And there's some truth to this claim. Find out why mammal milk is called "the perfect food" in this podcast from HowStuffWorks.com. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

As far as weight goes, Earth is a pretty hefty celestial body. But exactly how heavy? And how does one measure something so massive? Find out in this podcast from HowStuffWorks.com. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

Batteries are a common way to store energy, but there are many others. Discover more energy storage techniques, from falling weights to fuel cells, in this podcast from HowStuffWorks.com. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

We've all had a cold at one point or another; it entails an uncomfortable cocktail of symptoms like sneezing, coughing and a runny nose. But why do we get colds? How do they work? Find out in this podcast from HowStuffWorks.com. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

Three elements create a fire. Discover what they are and how dry chemical fire extinguishers combat them in this podcast from HowStuffWorks.com. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

Aluminum is both lightweight and strong, so it's no wonder that space stations, airplanes and thousands of other products use this metal. But where does it come from, and what makes it so special? Tune in to learn more. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.