CUE is a text file that describes how tracks are arranged in a super-audio CD and DVDs. Typically, CUE sheets come in plain text and have a filename extension of .cue. Today, this format is prevalent in most media players and optical disc authoring apps.
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AC3 is an audio format designed by Dolby Digital to offer surround sound listening. This format is available on most Blu-ray and DVD media files and is played using a Dolby Digital DVD Player. Interestingly, AC3 can be output in up to six speakers of a home stereo system. On a computer, AC3 can be opened on VLC Media Player, Apple QuickTime Player, and Windows Media Player.
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