A variety of podcast portals offer lists of podcasts; we walk you through some of the better neighborhoods in podcastland, explaining the basic mechanics that make podcasting work. Finally, as part of that technical introduction, we explain the technical origins and personal conflicts that color the podcast landscape. After this, if you just want to listen, you're ready to go. But we bet a big bag of fish that, after you've tried listening, you're going to want to start to speak with a podcast of your own.
The Basics of Listening
Listening is easy. Managing your subscriptions is easy. Keeping up with everything you can download with such ease is harder. That's because the listener is in control. Unlike broadcast media, where every listening choice is a zero-sum game, where choosing one program means you can't listen to the others, podcasting gives you the power to stack up a full schedule of listening and more.
First, you need to get an application commonly referred to as a "podcatcher," news reader, or aggregator. All these applications do the same thing; they visit a list of servers to check for newly posted files. A push client was locked to a particular server.
If you had multiple push services, it meant running several different applications. With podcast and RSS, your subscriptions are handled by one application. Later, we introduce you to the choices in podcatchers; here, we focus on what a podcatcher does.
As shown in Figure below, a podcatcher running on your computer maintains a list of subscriptions in the form of uniform resource identifiers (URIs, also called URLs) that tell the application the name of each server and where subscription files are stored on a regular schedule that you specify. Each subscription is referred to as a "feed," which is the Web address of a file that describes the catalog of shows stored in a particular directory on a server. You may have feeds for several different programs on the server, each with a unique URL for the XML file for each show.
For example, let's say you've subscribed to a podcast called Big Blue's Beer Show, which is stored on a server named http://www.bigblueBeer.com in a file called "podxml.xml." The full address of the file is http://www.bigbluebeer.com/site/feeds/podxml.com, and you've set your podcatcher to visit the site every day at 6:00 AM to check for new shows listed in that XML file. When the application finds a new show listed in the podxml.xml, the full audio file is downloaded to your PC and stored in a directory where you can open it and listen, or the podcatcher application can identify new audio or video files and move it to your computer or portable audio player. The podcatcher then moves to the next subscription on the list, in this case, a http://PodcastBible.com podcast, and checks that server for a new show. At the end of the update process, your podcatcher has a list of programs that are downloaded and ready for listening.
Of course, you can have your podcatcher visit many servers, collecting programs all day long, but remember that audio files take lots of space on the hard drive. An hour of MP3 audio is typically about 30 MB in size. Like a digital video recorder for your television, podcatchers require some tending, with frequent weeding to keep space available for new programs.
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