Codec stands for Coder/Decoder. Basically it is a piece of software or a
driver that adds a support for certain video/audio format for your operating
system. With codec, your system recognizes the format the codec is built for
and allows you to play the audio/video file (=decode) or in some cases, to
change another audio/video file into that format (=(en)code).

Software to determine what Video and Audio codecs are required to play a file:
Video Inspector


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A codec pack has many different codecs all in one installation, if you wish to

try out a codec pack, here are several popular ones:

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