VOB (Video Object) is a digital video container format usually found in DVD video media. VOB contains DVD video, audio, menu, and text data such as subtitles all multiplexed together. It typically includes MPEG-1 Part 2 or MPEG-2 Part 2 video codec encoded with AAC audio. Although this format is free, some copies might be encrypted.
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AU is an audio format standard in early web pages NEXT systems. It is also called u-law or Sparc-audio format. Typically, AU files can store audio data and annotation blocks. Initially, it was a headerless audio format, but newer versions have a header, thanks to the six unsigned 32.bit words.