A podcast is simply a list of media files that are stored on the internet, and that are retrievable by a program called a media aggregator (iTunes is one). When a new file is added to the list, an alert is sent to all subscribers' computers to download the most recent file(s). What this means for you is that you can have the latest sermons automatically downloaded to you computer every week.
If podcasting just isn't your thing, you can always listen to our sermons online! Just find the sermon you're looking for and click on its title to reveal the audio player.