CD-ROM (compact disk-read only memory) refers to a 4.75-inch, laser encoded, optical memory storage medium. Technologies include CD-ROM XA (extended architecture), CD-RW (rewritable), and CD-WO (write once).
The standard CD-ROM is approximately 120 mm in diameter and capable of data storage ranges from 650 to 870 MB. A smaller version of the CD-ROM, the mini CD ROM, is approximately 80 mm in diameter and holds approximately 150 MB of data. The first CD-ROM drive devices generally required an International Standards Architecture (ISA) bus card. Today, CD-ROM drive devices are generally self-powered, often self-contained, and typically interface with enhanced integrated drive electronics (EIDE), universal serial bus (USB), and small computer systems interface (SCSI) architectures. Data transfer rates commonly range from 1 to 7 MB per second.
CD-ROM (compact disk-read only memory) refers to a 4.75-inch, laser encoded, optical memory storage medium. Technologies include CD-ROM XA (extended architecture), CD-RW (rewritable), and CD-WO (write once).
The standard CD-ROM is approximately 120 mm in diameter and capable of data storage ranges from 650 to 870 MB. A smaller version of the CD-ROM, the mini CD ROM, is approximately 80 mm in diameter and holds approximately 150 MB of data. The first CD-ROM drive devices generally required an International Standards Architecture (ISA) bus card. Today, CD-ROM drive devices are generally self-powered, often self-contained, and typically interface with enhanced integrated drive electronics (EIDE), universal serial bus (USB), and small computer systems interface (SCSI) architectures. Data transfer rates commonly range from 1 to 7 MB per second.
CD-RW is a rewritable technology that permits writing and erasing much the same way as on a hard disk or 3.5-inch floppy disk. This type of compact disk uses a universal disk format (UDF) to permit packet writing in variable or fixed sizes, eliminating the need to write in tracks. CD-RW compact disks are often used as master copies for the production of standard CD-ROM disks (such as music CDs) because of this feature. A disadvantage is that a CD-RW drive can read a CD-ROM or CD-RW, but a CD-ROM drive cannot read a CD-RW. A modified version of rewriting to a CD-RW is a rarely used term known as CD-WO, which refers to writing once (WO) to a CD-RW, but then preventing any erasing or further writing. This process is also known as “closing” a disc.
CD-ROM XA (extended architecture) was developed by Microsoft, Philips and Sony in 1988. The XA architecture format permits the more accurate synchronization of data, audio, and video formats on multimedia. Form 1 of XA uses full error correction while Form 2 of XA drops one level to expand multimedia storage capabilities.
CD-ROM technology is relatively inexpensive and readily available in a number of formats and storage capacity limits. It has seen a consumer market sales decline recently, due to the advent of cost-effective DVD-RW+ (digital versatile disk-read/write) technology.