There are two specifications for rewritable DVDs: DVD-RW and DVD+RW (Digital Versatile Disk Rewritable). A DVD+RW disc can hold up to 4.7 Gigabytes of data or film and can be written to, deleted, and remade up to 1,000 times. DVD+RW DVDs are not as well supported by DVD machines because the rewritable surface is less shiny than write-once forms like DVD+R or commercially-pressed discs. A DVD+RW disc can only be written to with a suitable DVD+RW or Hybrid (DVD-RW) device.

Optical disk types that can be erased and rewritten include DVD+RW and DVD-RW DVDs. The data on a CD cannot be changed after it has been recorded; instead, it can only be read-only and cannot be altered. The format is a bad option for keeping data that need to be regularly changed as a result of this procedure. The rewritable CDs, on the other hand, are better suitable for routine data copies.

There are three lasers in an optical disc reader that can write discs: a low-power laser for reading data, a medium-power laser for wiping out rewritable discs, and a high-power laser for writing data to a disc. The mirrored coating of a phase change metal alloy on the bottom of the disc is burned with a sequence of dots by a DVD+RW drive. This metal combination initially appears as a transparent crystalline structure. The metal is heated by a strong blazing laser until it melts, at which point it becomes opaque and cools. The scanning laser in the drive scans and decodes the digital data that is encoded in these dark areas. The medium-powered erase laser is used by the drive to heat the metal layer to the condensation point when it's time to delete a disc.

The DVD+RW and DVD-RW disc formats were created by two different industry organizations as rival disc formats. The majority of rewritable optical disc drives are hybrid (DVD-RW) drives that can record to both types because the two are conceptually very similar.