This installation includes many of the most common codecs, available for free, like ffdshow, XviD, DivX and many others. Therefore you're giving other media players on your PC the same ability to playback media without the need of VLC Media Player. VLC Codec Pack is a fully-featured Windows codec pack which provides many of the video codecs which already come installed with VLC Media Player. Play downloaded movies and music in any media player with this codec pack.