Metadata for Digital Libraries: State of the Art and Future Directions (pdf) (source: JISC)

An overall framework for a digital object's metadata can be provided by either METS or DIDL, although the wider acceptance of the former within the library community makes it the preferred choice. Descriptive metadata can be handled by either Dublin Core or the more sophisticated MODS standard. Technical metadata, which is contingent on the type of files that make up a digital object, is covered by such standards as MIX (still images), AUDIOMD (audio files), VIDEOMD or PBCORE (video) and TEI Headers (texts). Rights management may be handled by the METS Rights schema or by more complex schemes such as XrML or ODRL. Preservation metadata is best handled by the four schemas that make up the PREMIS standard.

Via DigitalKoans