Alternatively referred to as a cd writer, CD-WO (Write once), WORM (Write Once Read Many) drive. CD-R is short for CD-Recordable and is a writable disc and drive that is capable of having information written to the disc once and then having that disc read many times after that. Data cannot be deleted from a CD-R disc and a CD-R disc cannot be formatted. If the data is not written to the disc properly, it cannot be corrected and is often jokingly referred to as a coaster.
The first recordable specification (CD-WO) was published in 1989 by Philips and Sony in the Orange Book. However, the drives were not popularized until Hewlett Packard released the HP 4020i in September 1995, which was the first sub $1,000.00 recordable disc drive.
CD-Rs are a low-cost solution for backing up software and only costs a few cents (as of 2010 around 17-cents a disc) and can hold up to 650 MB (74 minutes of music) or 700 MB (80 minutes of music). Although these are still a very popular solution for backing up data, more users are turning to DVD-R and USB thumb drives to backup and transfer their data today.
How does the CD-R work?
A CD-R disc is coated with a photosensitive organic dye that allows a user to record information. Once the CD-R disc is placed within the computer, the recording process begins. The laser inside the drive heats the dye to reveal areas that diffuse the light like a traditional CD pit. The CD-R drive does not create pits on the CD; instead the burner creates reflective sections on the CD causing the computer's CD-ROM laser to interpret it as a pit. Once a CD-R disc is finished recording, the CD can be used in any standard CD-ROM, CD-R, CD-RW, or DVD drive. Although, there were issues with the first revision DVD drives reading CD-R disc, today's drives no longer suffer from any reading problems.