DVD recordable and DVD rewritable refer to part of Optical disc recording technologies

Optical disc recording technologies

Optical disc authoring requires a number of different optical disc recorder technologies working in tandem, from the optical disc media to the firmware to the control electronics of the optical disc drive...

. DVD

DVD

A DVD is an optical disc storage media format, invented and developed by Philips, Sony, Toshiba, and Panasonic in 1995. DVDs offer higher storage capacity than Compact Discs while having the same dimensions....

 optical disc

Optical disc

In computing and optical disc recording technologies, an optical disc is a flat, usually circular disc which encodes binary data in the form of pits and lands on a special material on one of its flat surfaces...

 formats that can be recorded by a DVD recorder

DVD recorder

A DVD recorder , is an optical disc recorder that uses Optical disc recording technologies to digitally record analog signal or digital signals onto blank writable DVD media...

, (written, "burned"), either write once or rewritable (write multiple times) format written by laser

Laser

A laser is a device that emits light through a process of optical amplification based on the stimulated emission of photons. The term "laser" originated as an acronym for Light Amplification by Stimulated Emission of Radiation...

, as compared to DVD-ROM, which is mass-produced by pressing, primarily for the distribution of home video

Home video

Home video is a blanket term used for pre-recorded media that is either sold or rented/hired for home cinema entertainment. The term originates from the VHS/Betamax era but has carried over into current optical disc formats like DVD and Blu-ray Disc and, to a lesser extent, into methods of digital...

. DVD recordable is a general term that refers to both write-once and rewritable formats, whereas DVD rewritable refers only to rewritable formats.

Like CD-R

CD-R

A CD-R is a variation of the Compact Disc invented by Philips and Sony. CD-R is a Write Once Read Many optical medium, though the whole disk does not have to be entirely written in the same session....

s, DVD recordables use dyes. Depending on the intensity of the laser, the reflective property of the dye on a particular spot will determine whether it is a peak or a valley representation from pressed DVD. Dyes give the data side of a disc a distinct color. Dyes are also the reason playback is not guaranteed. Their reflective properties are not as good as with stamped DVDs that commonly have aluminum as the reflective layer.

Recordable DVDs are divided into three incompatible camps:

DVD-R

DVD-R

DVD-R is a DVD recordable format. A DVD-R typically has a storage capacity of 4.71 GB. Pioneer has also developed an 8.5 GB dual layer version, DVD-R DL, which appeared on the market in 2005....

/DVD-RW

DVD-RW

A DVD-RW disc is a rewritable optical disc with equal storage capacity to a DVD-R, typically 4.7 GB. The format was developed by Pioneer in November 1999 and has been approved by the DVD Forum. The smaller Mini DVD-RW holds 1.46 GB, with a diameter of 8 cm.The primary advantage of DVD-RW over...

 (DVD "minus" or DVD "dash"): First DVD recordable format released in the market. Developed by Pioneer

Pioneer Corporation

is a multinational corporation that specializes in digital entertainment products, based in Kawasaki, Kanagawa, Japan. The company was founded in 1938 in Tokyo as a radio and speaker repair shop...

 and backed by the DVD Forum

DVD Forum

The DVD Forum is an international organization composed of hardware, software, media and content companies that use and develop the DVD and formerly HD DVD formats...

. Has broader playback compatibility than the "+" especially with much older players. The dash format is based on an older CD-R/RW format for easy upgrade or migration for disc manufacturers.
DVD+R

DVD+R

DVD+R is part of optical disc recording technologies. It is a format for optical disc data storage that utilizes digital recording. It is similar to, but incompatible with, the older DVD-R standard...

/DVD+RW

DVD+RW

DVD+RW is a physical format for rewritable DVDs and can hold up to 4.7 GB. DVD+RW was created by the DVD+RW Alliance, an industry consortium of drive and disc manufacturers...

 (DVD "plus"): Developed by Philips

Philips

Koninklijke Philips Electronics N.V. , more commonly known as Philips, is a multinational Dutch electronics company....

 and Sony

Sony

, commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....

 with their DVD+RW Alliance

DVD+RW Alliance

The DVD+RW Alliance is a group of electronic hardware, optical storage and software manufacturers who in 1997 created and promoted a format standard of recordable and rewritable DVDs, known as the "plus" format. As of 2004, plus format DVDs were available in three forms: DVD+R, DVD+RW, and DVD+R...

. Introduced after the "-" format.
DVD-RAM

DVD-RAM

DVD-RAM is a disc specification presented in 1996 by the DVD Forum, which specifies rewritable DVD-RAM media and the appropriate DVD writers. DVD-RAM media have been used in computers as well as camcorders and personal video recorders since 1998.-Design:DVD-RAM is one of three competing...

 : As RAM stands for Random Access Memory, it works more or less like a hard-drive and was designed for corporate back-up use. Can only be read in drives that are DVD-RAM compatible. DVD Forum backs this format.

Michael Spath at CDfreaks analyzed the specifications of DVD-R/RW and DVD+R/RW formats and came to the conclusion that the DVD+R/RW format is superior to DVD-R/RW.

Multi-format drives can read and write more than one format; e.g., DVD±RW (DVD plus-dash rewritable) is used to refer to drives that can write/rewrite both plus and dash formats, but not necessarily DVD-RAM.

DVD recordable media are sold in two standard sizes, a standard-sized 12cm size for home recording and computer usage, and a small 8cm size (sometimes known as a miniDVD

MiniDVD

MiniDVD is a DVD disc having 8 cm in diameter.The 8 cm optical disc format was originally used for music CD singles, hence the commonly used names CD single and miniCD...

) for use in compact camcorder

Camcorder

A camcorder is an electronic device that combines a video camera and a video recorder into one unit. Equipment manufacturers do not seem to have strict guidelines for the term usage...

s and the like.

Speed

Drive speed	Data rate		Disc write time	Equivalent CD rate	Reading speed
1×	11.08 Mbit/s	1.385 MB/s	53 min	9×	8×–18×
2×	22.16 Mbit/s	2.770 MB/s	27 min	18×	20×–24×
4×	44.32 Mbit/s	5.540 MB/s	14 min	36×	24×–32×
5×	55.40 Mbit/s	6.925 MB/s	11 min	45×	24×–32×
6×	66.48 Mbit/s	8.310 MB/s	9 min	54×	24×–32×
8×	88.64 Mbit/s	11.080 MB/s	7 min	72×	32×–40×
10×	110.80 Mbit/s	13.850 MB/s	6 min	90×	32×–40×
16×	177.28 Mbit/s	22.160 MB/s	4 min	144×	32×–40×
18×	199.44 Mbit/s	24.930 MB/s	3 min	162×	32×–40×
20×	221.60 Mbit/s	27.700 MB/s	2 min	180x	32×–40×
24×	265.92 Mbit/s	33.240 MB/s	2 min	216x	32×–48×

Notes:

• DVD 1× actual spin is 3 times that of CD 1×
• Disk write time in table does not include overhead, leadout, etc.

Capacities

Most DVD±R/RWs are advertised as having a capacity of 4.7 GB. However these DVDs seem to hold less than the stated 4.7GB because many manufacturers quote the capacity of a DVD using decimal prefixes instead of the binary prefix

Binary prefix

In computing, a binary prefix is a specifier or mnemonic that is prepended to the units of digital information, the bit and the byte, to indicate multiplication by a power of 2...

es used by some software. This can be confusing for many users. While a 4.7 GB DVD can store 4.7 billion bytes: 4,700,000,000 bytes ÷ 1000 B/kB = 4,700,000 kB ÷ 1000 kB/MB = 4,700 MB ÷ 1000 MB/GB = 4.7 GB, using binary prefixes the same capacity is roughly 4.38 GiB

Gibibyte

The gibibyte is a standards-based binary multiple of the byte, a unit of digital information storage. The gibibyte unit symbol is GiB....

: 4,700,000,000 bytes ÷ 1024 B/KiB = 4,589,844 KiB ÷ 1024 KiB/MiB = 4,482.27 MiB ÷ 1024 MiB/GiB = 4.38 GiB.

Format	Decimal Prefix	Binary Prefix
DVD±R	4.70GB	4.38GiB
DVD±RW	4.70GB	4.38GiB
DVD±R DL	8.55GB	7.96GiB
DVD-RAM	4.70GB	4.27GiB
DVD-RAM DL	9.4GB	8.75GiB
MiniDVD	1.46GB	1.36GiB
MiniDVD DL	2.66GB	2.48GiB

Longevity

See also: Optical disc recording technologies#Longevity

According to a study published in 2008 by the Preservation Research and Testing Division of the U.S. Library of Congress, most recordable CD products have a higher probability of greater longevity compared to recordable DVD products.