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The DVD-R Format

Media Type: Write-once, read-many
Recording Technique: 650-nanometre laser at 8-10 milliwatts
Disk Surface: Organic dye
Write Speed: 1X or 2X or 4X
Capacity: Single - 4.7GB, Double - 9.4GB
Industry Support: Authorised by the DVD Forum
Introduction to DVD-R
DVD Recordable (DVD-R) was originally developed with compatibility in mind and can be
played on practically all DVD players and DVD-ROM drives.
It is a write-once, read-many (WORM) media that can store many types of information music, data, multimedia, photos, illustrations, audio and so on.
One Standard Becomes Two
In 2000, the DVD-R format was separated into two: DVD-R for Authoring Version 2.0 and
DVD-R for General Version 2.0.
DVD-R for Authoring was targeted at professional authoring of DVD content, and DVD-R
for General was targeted toward the consumer market.
The division of the standard was primarily due to copyright and copy generation management.
The DVD-R for General format includes a particular disk area that can prevent copies being
made. The Lead-in Area of each disk is also equipped with an optional NBCA data space for
copy generation management. See Copy Protection for more detail on the application of copy
protection technologies.
Capacity
The original DVD-R for Authoring can store 3.95 billion bytes (Giga-Bytes or GB) of
information. The DVD-R for General can store even more at 4.7GB.
When each side of a DVD-R disk is used, one disk can hold up to 9.4GB of information.
The DIsk Surface
The DVD-R format is write-once because during the recording process a high-powered (8-10
milliwatt) infrared laser permanently changes the disk surface.
The surface itself is a dye-coated polycarbonate substrate. The substrate forms the outside
surface of the disk, and beneath that the dye forms the recording layer.

The dye is spin-coated onto the substrate when the blank disk is first manufactured.
The surface of each DVD has a microscopic spiral track, or groove. The groove is used to