High-definition optical disc format war that involved compressing HD content onto dual-layer DVD-9 discs. In spite of this decision, the DVD Forum's Steering Committee announced in April 2002 that it was pursuing its own blue-laser high-definition solution. In August, Toshiba and NEC announced their competing standard Advanced Optical Disc, which was finally adopted by the DVD Forum and renamed "HD DVD" the following year after being voted down twice by Blu-ray Disc Association members, prompting the U.S. Department of Justice to make preliminary investigations. Three new members had to be invited and the voting rules changed before the initiative finally passed. The competing standards had
Optical disc drive inexpensive, are suitable where read/write capability is required. Disc recording is restricted to storing files playable on consumer appliances (films, music, etc.), relatively small volumes of data (e.g. a standard DVD holds 4.7 gigabytes) for local use, and data for distribution, but only on a small scale; mass-producing large numbers of identical discs is cheaper and faster than individual recording. Optical discs are used to back up relatively small volumes of data, but backing up of entire hard drives, which typically contain many hundreds of gigabytes or even multiple terabytes, is less practical. Large backups are often instead made on