Optical disc drive operations, and the last speed for read-only (ROM) operations. For example, a 40×/16×/48× CD writer drive is capable of writing to CD-R media at speed of 40× (6,000 KB/s), writing to CD-RW media at speed of 16× (2,400 KB/s), and reading from a CD-ROM media at speed of 48× (7,200 KB/s). During the times of combo (CD-RW/DVD-ROM) drives, an additional speed rating (e.g. the 16× in 52×/32×/52×/16×) is designated for DVD-ROM media reading operations. For DVD writer drives, Blu-ray disc combo drives, and Blu-ray disc writer drives, the writing and reading speed of their respective optical media are specified in
DVD+R DL DVD+R DL DVD+R DL (DL stands for Double Layer) also called DVD+R9, is a derivative of the DVD+R format created by the DVD+RW Alliance. Its use was first demonstrated in October 2003. DVD+R DL discs employ two recordable dye layers, each capable of storing nearly the 4.7 GB capacity of a single-layer disc, almost doubling the total disc capacity to 8.5 GB. Discs can be read in many DVD devices (older units are less compatible) and can only be created using DVD+R DL and Super Multi drives. DL drives started appearing on the market during mid-2004, at prices comparable to