Dave Winer defines the newest buzzword:
Think how a desktop aggregator works. You subscribe to a set of feeds, and then can easily view the new stuff from all of the feeds together, or each feed separately.
Podcasting works the same way, with one exception. Instead of reading the new content on a computer screen, you listen to the new content on an iPod or iPod-like device.
Think of your iPod as having a set of subscriptions that are checked regularly for updates. Today there are a limited number of programs available this way. The format used is RSS 2.0 with enclosures.
In the future, radio shows like All Things Considered and Rush Limbaugh will be available in this manner, and perhaps other syndication formats will support enclosures.
Podcasting allows you to subscribe to feeds, which include links to audio programs. Every time one of your subscriptions posts a new program, it automatically downloads onto your computer. You then transfer those shows to a portable music device, listen to it throughout your house via a wireless connection or take it with you wherever you go. Think of it as a personalized radio station that you program and change whenever you want.
The technical explanation is a bit more complex. The idea originally grew out of the Apple iPod community, where Adam Curry helped develop a piece of software called iPodder. iPodder automatically routes an audio program to an iPod and makes the process relatively seamless. It wasn’t long before similar solutions sprung up for use with other devices.
The programs are delivered via an RSS feed, and there are already millions of computer users subscribing to at least a few text feeds of blogs and other sites. The RSS feed contains a link, which notifies your computer that a new audio program is available and begins downloading it into a pre-selected spot on your computer.
Podcasting — like blogging — seems to combine the best of the Internet with the best of traditional media. It’s a way for someone to create and distribute a show to 40 people. And it also would allow a media company to distribute audio content to millions.