sentences:  Dolby Digital Plus (DD-Plus) and TrueHD are supported in HD DVD, as mandatory codecs, and in Blu-ray Disc, as optional codecs.In the LaserDisc world AC3RF is the acronym widely placed on connectors of players that support Dolby Digital.Specific demodulators and receivers from the LaserDisc era (1990s thru early 2000s) also include placement of this acronym on connectors.