Sonar uses sound to gauge the distance between objects. Although most people associate sonar with submarines, humans use sonar for a lot more than underwater navigation. In this episode, Jonathan and Chris take a look at the mechanics behind sonar.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