DualDisc
DualDisc is an optical disc format for storing digital data promoted by the RIAA. Essentially, DualDisc is a combination of a compact disc (CD) with a DVD, with one format on one side of the disc and the other on the opposite. Some consider DualDisc to be the DVD-Forum's way of competing with the Super audio compact disc (SACD) format, which to date Sony and Philips promote.
The inclusion of additional contents is considered an incentive to slow down copyright infringing file sharing. As of early 2005, several music albums are released in the United States in this format only.
There has been some controversy surrounding the DualDisc format as of late, as a German inventor of the DVD Plus specification claims that DualDisc is in violation of its essential patents.
High profile releases in this format include Nine Inch Nails' remastered The Downward Spiral and Duran Duran's Astronaut. The latter, ironically, is released on Sony BMG Music Entertainment, a subsidary of the co-creators of SACD.