A lot of the time we spend on the internet today is spent not only reading but listening and watching media online like movies, previews, game movies, funny adds and cartoons ... broadband makes this very easy. On some ISP?s you can download a 2.5 hour movie in under 1 hour. One thing that confuses and annoys people still, however, is codecs. A codec, in terms of the context of this article, is a software algorithm that compresses digital video and/or audio and also decompresses them for playing. The overriding goal of most codecs is to reduce file size whilst maintaining quality. Most users essentially install a plug-in for their players that decompresses only. Unless the codec has been developed under open source standards you generally have to purchase a full copy if you want to compress your own files as well as simply use the codec to play files. Once you have downloaded and installed a codec, it is simply used by your player to play files that use it. Codecs are not separate programs or players however some codecs such as DivX are provided with their own player.

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