QuickStudy: Podcasting

Computerworld - When Apple Computer Inc. introduced its handheld music player, the iPod, in 2001, few anticipated that it would spawn -- and even give its name to -- a new public medium for information dissemination. But in little more than a year since it first hit national consciousness in the fall of 2004, podcasting has become a significant channel for distributing audio materials.

Podcasting marks both the expansion of radio/audio publishing (with video likely to join them soon) into a populist, subscriber-based medium and the freeing of such programming from the strictures of real-time listening.

The term itself, made by combining "iPod" and "broadcasting," encompasses three distinct elements:

1. Programming: Podcasters create audio programs, usually in the form of MP3 files, which they upload to Web sites. Anyone with a computer and a microphone can now create audio programming.

   Podcasts range in format from crude, bloglike individual diaries featuring personal rants and ramblings to slick, professionally produced interviews and discussions and redistributed programming from commercial and public broadcasting organizations. The subjects of podcasts cover the gamut of human interest and experience.

2. Publication and subscription: This takes place via Web sites that index and facilitate the finding of and subscription to podcasts according to subject matter, source, creator, metadata tags and other criteria. Podcasting differs from other types of online media distribution in that it's largely organized on a subscription model, using automatic feeding mechanisms (such as RSS or Atom) to deliver files to audiences.

   In addition, a number of Web sites now catalog thousands of available podcasts, which the user can download or subscribe to with a simple click.

3. Playback: A user simply downloads a podcast to his computer and subsequently transfers it (often automatically) to an iPod or other music player for listening to at his convenience and not the broadcaster's schedule. VCRs and then TiVo liberated television viewers from having to adhere to broadcasters' schedules. Now, podcasting has extended such capability to mobile players for audio and radio programming.

   Access is simplified by subscription and by the automatic transfer of downloaded podcasts from a computer to a portable music player when the player is docked.