Podcasts were originally audio, many are now video (some are called webcasts). Many series offer subscriptions and most sites offer the choice of listening immediately or downloading for your own future use from your computer or portable player (e.g. iPod, tablet).
Assorted podcasts or build your own
Extensive, indexed in 16 categories
Podcasts created by Library of Congress
Science Talk and 60-second Science in podcasts
Center for Disease Control podcasts
- Apple’s Podcasts (for searching and archiving) is now part of the Catalina OS (for desktops and laptops), and available in their AppStore as iOS for tablets and cellphones.