price of about $17,000. The original capacity was 3.5GB or 3.95GB, which was
later expanded to 4.7GB. The discs, which now cost as little as 60–75 cents
apiece, use an organic dye for one-time recording.DVD-RW
The DVD-Rewriteable followed the same 4.7GB specification as the DVD-R
when it was released in 1999. Early versions of DVD-RW record only on discs
identified as meeting the DVD-R or DVD-RW standard and are best suited for
video and audio; data error detection and correction facilities are limited.
Discs use a chemical that changes their phase from reflective to nonreflective
when touched by heat. These discs sold for about $2.00 each in 2005.DVD+RW
This competing rewriteable standard was supported by a consortium of man-
ufacturers in competition with the DVD Forum and introduced in 2001; today
discs sell for about $1.75–2.00. It has the same 4.7GB capacity and has some
advantages, including higher speed recording and improved facilities to
handle video, audio, and data. Discs use a chemical that changes phase from
reflective to nonreflective when struck by the laser beam’s heat. The original
DVD+RW drives can read prerecorded DVDs and CDs, and usually can also
read DVD-Rs and DVD-RWs, but can only record on DVD+R or DVD+RW discs.
If that sentence doesn’t make sense, go back and pay attention to the differ-
ence between the dash and the plus in the names. DVD-R is not the same as
DVD+R. Don’t blame me, I’m just the messenger.DVD+R
This write-only version of a 4.7GB DVD was created and supported by the
same group of manufacturers responsible for DVD+RW. In 2005, these discs
sold for about 60–75 cents apiece.DVD-RAM
This 4.7GB specification seems destined to fall by the technological wayside.
It requires use of a cartridge to hold the disc; Type 1 is a sealed container,
while Type 2 permits the disc to be swapped. Inconvenient, and a bit more
expensive, it also is not particularly well suited to laptop use.DVD+R DL and DVD+RW DL
These Dual (or Double) Layer discs allow a laser to change its focus between
one or the other layer with a capacity of about 86GB. In 2005, dual-layer
DVD+R sold for about $5 apiece.What does this mean to you as a user? Get the right one for your player. If
you have a brand-new laptop, it may well have a DVD+RW or DVD+R device
that can also use DVD-RW or DVD-R discs. Sorry, but I can’t see your machine
from here: Check the documentation that came with your machine or call
customer support for advice.156 Part III: Laying Hands on the Major Parts