A podcast is a series of digital-media files which are distributed over the Internet using syndication feeds for playback on portable media players and computers. The term podcast, like broadcast, can refer either to the series of content itself or to the method by which it is syndicated; the latter is also called podcasting. The host or author of a podcast is often called a podcaster.
The term is a portmanteau of the words "iPod" and "broadcast", the Apple iPod being the brand of portable media player for which the first podcasting scripts were developed (see history of podcasting). Such scripts allow podcasts to be automatically transferred to a mobile device after they are downloaded.
Though podcasters' web sites may also offer direct download or streaming of their content, a podcast is distinguished from other digital media formats by its ability to be syndicated, subscribed to, and downloaded automatically when new content is added, using an aggregator or feed reader capable of reading feed formats such as RSS or Atom.

Receiving and using podcasts
Making full use of podcasts' syndication features requires appropriate software, often referred to as a podcatching client or a podcatcher. The feeds are usually distributed using RSS or Atom protocols to the podcatching client. The dominant podcatching client is Apple's iTunes player. However, there are alternatives, including Microsoft's Zune Marketplace, Mediafly SyncClient (windows), Juice (multiplatform), Doppler (Windows), Podget (Linux) and Podracer (Linux). Some established audio players, such as Amarok, Winamp and Mediamonkey also offer (sometimes limited) podcatching functionality. Podcasts are also available directly on emerging internet-enabled devices, such as the chumby.
Many podcasts also allow users to direct download, by giving a link to the audio file in an RSS feed or web page. (Wikipedia, 2008)

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