Podcasts are audio content that can be downloaded or streamed online, typically in a series format. They cover a wide range of topics and can be educational, entertaining, or informative. If you are interested in learning more about podcasts, there are many books available that can help you understand the history, production, and impact of podcasting. Some popular books on podcasts include "Podcasting for Dummies" by Tee Morris and Chuck Tomasi, "The Podcasting Handbook" by John Lee Dumas, and "Podcast Launch" by John Lee Dumas. These books can provide valuable insights and tips for starting your own podcast or improving your listening experience.