A podcast is a
|“||digital media file, either audio or video, that [is] downloaded directly or [is] streamed webcasting.||”|
"Podcasting" is a portmandeau of "broadcasting" and "iPod."
It is a way of publishing audio files (and more recently video files) on the web so they can be downloaded onto computers or portable music players. Podcasting allows users to subscribe to a feed of new audio files using software which automatically checks for and downloads new files.