6.5 Conclusion

DVD-R and DVD-RW are recordable and re-recordable DVD standards recognized by the DVD Forum, defined in accordance with the basic concept of providing compatibility with read-only discs.
As applications for these recordable media, the DVD Forum has established the Video Recording format, which provides excellent support for features such as video editing, and the DVD Video format (for non-copy-protected data only), which is primarily concerned with providing compatibility with the existing DVD-Video specification. These specification are available today for use in certain applications.
The DVD-R and DVD-RW specifications were promulgated somewhat later than the read-only specification, and as a result there are some compatibility issues with some of the earlier DVD players and drives. (For example, some players cannot recognize DVD-R/RW discs because the aforementioned Book Type flag is different from those of ROM discs, or because DVD-RW discs are single-layer discs but have the same reflectivity as dual-layer discs.) Recently, however, as a result of increased recognition of these specifications, standardization efforts such as RWPPI (the RW Products Promotion Initiative), and due to continuing efforts by manufacturers to improve product quality, compatibility problems and user inconveniences in the market should be considerably reduced.
Hand in hand with the increasing popularity of DVD video, audio, and ROM, we anticipate that DVD-R and DVD-RW will also quickly establish a large recordable DVD market.

FROM: http://www.pioneer.co.jp/crdl/tech/index-e.html