Podcasts are similar to radio transmissions, but they are digital media frequencies distributed over the Internet to portable media players or a computer system, with the help of syndicate feeds. Podcasts may be media files either in the audio or video formats. The term Pod casts was first coined by Apple, as they were initially used to broadcast feeds on an iPod. Since Pod casts can now relayed on a computer system as well with the help of feed readers like Atom and RSS feeds, the term Podcasts was redefined by some as "Personal On Demand broadCASTS". The most predominant player in the Podcasting arena is the "Apple iTunes" player.