Simply, the storage capacity of a dual-layer Blu-Ray disc is 50GB while the maximum a HD DVD disc can hold is only 30GB. Since the writable discs will only be single layer, the Blu-Ray and HD DVD discs will whole 25GB and 15GB respectively. Any other differences between the discs are negligible.
More storage capacity means more special features, longer video, or most unlikely, better quality video compression. (Consumers tend to choose longer play over picture quality, which explains the popularity of VHS’s EP mode for recording.)
Betamax died off quickly mainly because movie studios, when forced, supported the VHS format because it was technologically inferior. The public didn’t seem to mind. The VHS devices were cheaper, and with a format that ensured lower-quality copies, the movie studios felt their product was safer in the hands of the public.
Updated February 6, 2012 and originally published November 30, 2004. If you enjoyed this article, subscribe to the RSS feed or receive daily emails. Follow @flexo on Twitter and visit our Facebook page for more updates.