One of the major achievements of DVD is that it has brought all the conceivable uses of CD for data, video, audio, or a mix of all three, within a single physical file structure called UDF, the Universal Disc Format. Promoted by the Optical Storage Technology Association (OSTA), the UDF file structure ensures that any file can be accessed by any drive, computer or consumer video. It also allows sensible interfacing with standard operating systems as it includes CD standard ISO 9660 compatibility. UDF overcomes the incompatibility problems from which CD suffered, when the standard had to be constantly rewritten each time a new application like multimedia, interactivity, or video emerged.

The version of UDF chosen for DVD-Video to suit both read-only and writable versions - is a subset of the UDF Revision 1.02 specification known as MicroUDF (M-UDF).

Because UDF wasn't supported by Windows until Microsoft shipped Windows 98, DVD providers were forced to use an interim format called UDF/ISO (UDF Bridge).

UDF has been revised and now appears in revisions 1.02, 1.5, and 2.0.
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