Podcast is a Web-based audio broadcast system via an RSS feed, accessed by subscription over the Internet
Easier To Understand:
Podcast an audio file which you can download and listen too
A few years ago, the word podcast was a term that many were not familiar with. But even today, it is still needs something that is only beginning to pick up in popularity. While the average tech-geek may throw the term around here and there and seem familiar with it, they can actually be using it incorrectly. For instance, they can download an audio file to show off the Internet to listen on their computer but that is not the truly podcasting. Podcasting involves with subscribing to an RSS feed that downloads the show to their gadgets like iPod or MP3 player for listening.