what is a podcast. Can anyone explain

A podcast is a multimedia file that is distributed by subscription (paid or unpaid) over the Internet using syndication feeds, for playback on mobile devices and personal computers. Like "radio", it can mean both the content and the method of broadcast. The latter may also be termed podcasting. The host or author of a podcast is often called a podcaster. Though podcasters' Web sites may also offer direct download or streaming of their content, a podcast is distinguished from other digital audio formats by its ability to be downloaded automatically using software capable of reading feed formats such as RSS or Atom. details at http://en.wikipedia.org/wiki/Podcast