DVD-Video dispute between Chinese companies and On2 Technologies, but on December 6, 2006, 20 Chinese electronic firms unveiled 54 prototype EVD players and announced their intention for the format to completely replace DVDs in China by 2008. However, due to a lack of sales, support for EVD has recently been dropped by the Xinhua Bookstore in Wuhan, which was a major supporter of the format. Two competing high-definition (HD) optical-disc formats, HD DVD and Blu-ray, were introduced in 2006. The HD DVD format, promoted by Toshiba, had the backing by the DVD Forum, which voted to make it the official successor
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