Are they identical to normal CDs?
(2005/01/03) CD-ROMs and music CDs you commonly find in stores are pressed from a glass mold. CD-Rs are burned with a laser. They may look different (often green, gold, or blue instead of silver), they’re less tolerant of extreme temperatures and sunlight, and they’re more susceptible to physical damage. Whether CD-Rs or pressed CDs last longer is difficult to answer. While they’re not physically identical, they work just the same. Some CD players and CD-ROM drives aren’t as good at reading CD-R and CD-RW discs as they are at reading pressed CDs, but by and large they work just fine. By the way, you can’t record on pressed discs, so you might as well throw out all those AOL CD-ROMs you’ve been accumulating (or try one of the suggestions in section (7-9)). Buying a bunch of old CDs in the hopes of writing new stuff onto them is a bad idea. For similar reasons you can’t record on DVD media, not even DVD-R and DVD+RW, unless your drive explicitly supports the DVD formats. You have to buy
(1999/12/19) CD-R is short for “CD-Recordable”. Recordable CDs are WORM (Write Once, Read Multiple) media that work just like standard CDs. The advantage of CD-R over other types of optical media is that you can use the discs with a standard CD player. The disadvantage is that you can’t reuse a disc. A related technology called CD-Rewritable (CD-RW) allows you to erase discs and reuse them, but the CD-RW media doesn’t work in all players. CD-Rewritable drives are able to write both CD-R and CD-RW discs. All CD recorders can read CDs and CD-ROMs, just like a standard CD-ROM drive.
The CDs you buy in a store are pressed from a mold. CD-Rs are burned with a laser. They may look different (often green, gold, or blue instead of silver), they’re less tolerant of extreme temperatures and sunlight, and they’re more susceptible to physical damage. Whether CD-Rs or pressed CDs last longer is difficult to answer. While they’re not physically identical, they work just the same. Some CD players and CD-ROM drives aren’t as good at reading CD-R and CD-RW discs as they are at reading pressed CDs, but by and large they work just fine. By the way, you can’t write data onto pressed discs. Buying a bunch of old CDs in the hopes of writing new stuff onto them is a bad idea. You have to buy blank CD-R or CD-RW media.
