The term 'podcast' was coined in February 2004 when journalist Ben Hammersley, writing for the Guardian, proposed several suggestions for a new word meaning 'listening to audioblogs'.
The neologism, which has now entered the Oxford English Dictionary, was derived from the two terms 'Ipod' and 'broadcast', in spite of the fact that, strictly speaking, podcasting does not require an Ipod (or any other portable player) and no traditional broadcasting is involved.
It was just that Ipods were gaining in popularity when podcasting began and no other name has succeeded in catching on.
While the mechanics of how podcasting works are highly technical, the essence lies in enabling viewers to watch and listen to whatever they want, whenever they want, hence its popularity.
While it's certainly true that podcasts were originally audioblogs, they now cover a much wider area, including video content. Radio shows are frequent. Numerous religious groups provide talks ('godcasts').
News organisations and commercial companies supply informational podcasts. Political parties and individual politicians in the US put out broadcasts; George Bush's weekly radio address is available as a download, while Tony Blair and David Cameron have been interviewed on podcasts.
Apple has added a podcast directory to its Itunes online music store and, as the ultimate accolade, even the staid BBC now podcasts a growing selection of its programmes.
There's money in podcasting, too. London's LBC radio station was the first to replace its free-to-air podcasts with a financially viable subscription service. And the Ricky Gervais Show, officially the world's most downloaded podcast, now charges a fee.
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