For years now, radio has been a slowly dying medium. Most music stations tend to only play a few recent songs repetitively. The few shows that don't fall prey to this are often independently run and perpetually underfunded. One of the only saving graces of radio today is talk radio, but even that is lacking in available content. Enter podcasting-a method of automatically distributing audio content over the Web. While this may not seem revolutionary, podcasting may end up being one of the most significant, yet simple, technological leaps on the Web.

Online radio shows have existed ever since streaming technology met with broadband Internet access. Although these online shows cover a wide variety of topics, they have never surpassed their radio roots-instead of being tied to a radio, you're tied to a computer. Eventually, these shows began to offer downloadable MP3 versions, which made it possible to listen to them in a variety of other ways. You could, for example, turn them into an audio CD, or transfer them to your portable audio player. It was the latter option that served as the catalyst for podcasting.

A podcast consists of an audio file automatically delivered by a web syndication feed. Two popular examples of syndication feeds are Really Simple Syndication (RSS) and Atom. These technologies allow users to subscribe to Web sites and easily see when they are updated and are often used for news sites and blogs. In the case of podcasting, audio files are syndicated instead of Web pages.

After subscribing to a podcast feed, new episodes are automatically downloaded as they become available. This simple bit of automation is the crux of what has made podcasting such a phenomenon. Instead of manually checking to see if your favorite online show has been updated, it all happens without your intervention. When you're following multiple shows, having this process automated can be a real timesaver.

Another novel aspect of podcasts is that the shows can be synchronized with portable audio players. This is where the "pod" in podcasting comes from. The name is actually somewhat misleading because an iPod isn't required to realize the full potential of podcasting. The name has stuck, however, despite attempts to change it to something more universal.

So why is podcasting so popular, when it's basically just automating technology that's several years old? It may simply be that it showed up at just the right time. More people than ever own digital audio players, and they're all looking for more audio content. Podcasts are also free and cover many areas of interest, making them the perfect source of content for filling up portable players. Many traditional radio shows, including a few NPR shows, are also available in podcast form. In the end, podcasting is doing for radio what TiVo did for television; it allows us to choose what we want to hear, and when we want to hear it.

Podcasting is accessible to everyone. Pretty much anyone can create a simple podcast and make it available online. While this leads to lots of shows that aren't worth your time, there is the occasional gem. For some, podcasting is also doing the work of a traditional blog; podcasting is often referred to as audioblogging.

If you want to join the podcasting revolution, there are many ways to go about it. I recommend the program iPodderX, one of the first podcast programs. Apple has also recently taken advantage of podcasting by implementing it in iTunes, as well as by creating a podcast section in the iTunes store. Various Web sites, such as podcast.net, collect various podcast feeds. If you're interested in starting your own podcast, there are many easy-to-follow tutorials online. The IT department will also be offering a class over Interterm on starting a podcast; the class will cover the basics of recording and editing audio and generating a podcast feed.