Optical Disk Storage Options
In computing terms, an optical disk is a circular, flat disk which can be used to store and encode data values. It is generally made from a mixture of aluminium and a polycarbonate material, and encodes data in a spiral pattern continuing around the disk beginning at the middle of the disk and ending on the edges. Data is encoded using a laser or stamping machine, and is read when the disk is spun in a special optical disk drive lit up by a laser diode light. The reflections from this allow the machine playing the disk to interpret the data stored there in a binary format, which can then be translated into sound, text or images according to whatever is stored on the disk.
‘CD-ROM’ stands for Compact Disc Read-Only Memory. This is a type of optical disk which is used to typically store data. Computers and machines can read the data held on these disks but cannot erase or alter them. Standard CDs are 120 millimeters in diameter and can hold up to 700mb of data, or approximately 80 minutes of audio files.
CD-ROMs can be used in a CD player, while regular CD-ROMs holding data can only be used on a computer. Compact Disks follow the standard format defined and developed by Sony and Phillips in the Compact Disc Digital Audio format, often called the ‘Rainbow Books’ which contain all of the details and specs for all types of CDs.