Dual layer recording allows DVD-R and DVD_plus_R discs to store significantly more data, up to 8.5 Gigabytes per side, compared to 4.7 Gigabytes for single-layer discs. DVD-R DL was developed for the DVD Forum by Pioneer Corporation, DVD+R DL was developed for the DVD+RW Alliance by Philips.
DVD recordable discs supporting this technology are backward compatible with most existing DVD players and DVD-ROM drives. Many current DVD recorders support dual-layer technology, and the price point is comparable to that of single-layer drives, though the blank media remains significantly more expensive. Currently the technology has severe problems with compatibility in DVD players.