Nails are measured by a unit called a penny. This podcast from HowStuffWorks.com explains what the penny designation means -- and where it comes from.
Learn more about your ad-choices at https://www.iheartpodcastnetwork.com

Why Is Siberia's Batagaika Crater Known as the Doorway to Hell?
11:10

BrainStuff Classics: How Would Authorities Handle a Murder in Space?
08:17

How Does Taste Work?
13:59