Also known as cDVDs, they basically consist of DVD video written onto a CD-R or CD-RW disc. A miniDVD can only fit about 15 minutes of video per CD. It doesn't work in most standalone DVD players because:
- the DVD player usually identifies the miniDVD as a VideoCD/Super VideoCD or Red Book audio CD instead of a DVD Video disc
- the high bitrate of DVD video means that the reader must support reading at 8x and most players only support 2x maximum
However, a miniDVD will work on some standalone DVD players and all computers with DVD-ROM drives and software DVD players.
Note: Cheers to WWWWolf for pointing out a potential point confusion with the "mini DVDs" used in the Nintendo Gamecube. Gamecube discs are actually physically the same as 3" DVDs, except they are recorded from the outside in.1
1. Thanks go to mkb for pointing this out. Originally I had written that they are smaller-diameter discs that were physically identical to DVDs, which is clearly not the case.
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