abstract:Universal File Format is a file format originally developed by the Structural Dynamics Research Corporation (SDRC) to standardize data transfer between computer aided design (CAD) and computer aided test (CAT) software packages.
So if you pop in a DVD "infected" with Protect DVD-Video, it can't be read by Windows Media Player, Media Center Edition, or any DirectShow-based software, thanks to a Universal Disc Format that tricks your machine into believing that the IFO file is zero bytes long.