What is a podcast

A podcast (portmanteau of pod as in "ipod" and broadcast) is a radio show distributed on the internet, usually for free. Podcasts are usually ordinary mp3 files, distributed through RSS feeds. Some podcasts are in video form, also known as "vodcasts".

Podcasts cover virtually all topics, and are produced by corporations and individuals alike.

What is a podcatcher?

A podcatcher is an "aggregator" (downloader and player of podcasts). A podcatcher simplifies the listening of podcasts by allowing subscriptions and managed download of podcast shows.