According to the study released by the Pew Internet and American Life Project, more than 22 million American adults own iPods or MP3 players and 29% of them have downloaded podcasts from the Web so that they could listen to audio files at a time of their choosing. That amounts to more than 6 million adults who have tried this new feature that allows internet "broadcasts" to be downloaded onto their portable listening device.
A podcast, named by combining iPod and broadcast, is basically an audio blog, a program recorded into an MP3 file that you can post or pick up at sites online. You don't need an iPod to create or listen to one. They can be legally played onto any digital audio player, not just an iPod.
Podcasters create radio-like programs of commentary, music or humor, which are posted online. Listeners are automatically notified when a new podcast is available.