Comparison of high definition optical disc formats Blu-ray disc players since the end of the format war. Blu-ray Disc has a higher maximum disc capacity than HD DVD (50 GB vs. 30 GB for a double layered disc). In September 2007 the DVD Forum approved a preliminary specification for the triple-layer 51GB HD DVD (ROM only) disc though Toshiba never stated whether it was compatible with existing HD DVD players. In September 2006 TDK announced a prototype Blu-ray Disc with a capacity of 200GB. TDK was also the first to develop a Blu-ray prototype with a capacity of 100GB in May 2005. In October 2007 Hitachi developed
The Hitchhiker's Guide to the Galaxy Tertiary to Hexagonal Phases released on 2 October 2006 in the UK. This marks the first commercial release of any BBC radio programme in a 5.1 surround mix. The disc contains as extras: the full version of the Krikket Song, a photogallery, the original online and radio trailers, the appearance of the series on Pick of the Week, and thirty minutes of behind the scenes video in five short segments. Note that while the BBC online shop is still listing the disc as a DVD-Audio disc, their own image confirms that the disc is a lower-definition standard DVD-Video. . Since the opening of the