Toshiba announced on Tuesday the development of a higher-capacity HD DVD disc. HD DVD is the format the electronics maker is promoting as the next-generation DVD disc format. Previous versions of the format allowed for the storage of up to 30GB, but the latest version can read into a third layer on an HD DVD disc so it can hold up to 45GB of data. The 45GB version of the disc is a read-only version. Toshiba also announced a double-sided, dual-layer, hybrid read-only disc storing up to 30GB on the HD DVD side of the disc and 8.5GB on the standard DVD dual-layer side of the disc.

The increase in disc storage capacity is partly in response to a competing format, Blu-ray Disc, which supporters such as Sony are also trying to establish as the next-generation DVD disc format. Blu-ray Disc can store up to 50GB of data on a dual-layer disc.
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