Audio Decoders:

An audio decoder is a piece of hardware or software that decompresses digital audio data that has been compressed into a certain format. For a product to have certain audio decoders means that it can play back audio from discs or video files that have audio tracks in that format. For example, if a receiver has a Dolby Pro Logic II audio decoder, that means it can play audio from movies that have Dolby Pro Logic II-encoded audio.