A podcast is an MP3 or other audio file delivered off a Web site via an RSS feed.
Let’s break it down. Podcast is derived from the terms “iPod” and “broadcast”. It is attributed to the original creators of podcasting who used iPods to listen to their RSS broadcasts. Then Apple added an RSS reader to the iTunes software, making it simple for anyone with an iPod to subscribe and listen to podcasts. All you need to know is the URL of the RSS or XML.