A rewritable optical disc. First used in drives by Panasonic in the late 1980s, the phase change technology was subsequently employed in all major optical drives, including CD-RW, DVD-RW ...

HD DVD-ROM discs (read-only), and HD DVD-RW discs (rewritable): back-to-back bonding of two 0.6 millimeter-thick substrates. The new disc also shares key manufacturing processes with DVD-R ...