How can a single piece of glass look like a mirror from one side but a window from the other? Learn how materials technology makes it possible in this episode of BrainStuff.Learn more about advertising on the HowStuffWorks podcasts at www.howstuffworks.com/advertisers.htmAnd to learn about your ad choices when listening to podcasts, visit https://www.howstuffworks.com/privacy.htm#ad-choices
