Thursday, July 30, 2009

How Long Does A Cd Last

Much backup data is recorded on CDs. This includes irreplaceable personal memories, such as photos, as well as vital personal business documents, such as old tax returns. Many businesses have used CDs as a backup system as well. Therefore, the question of how long a CD will last becomes important. The response is that contrary to popular belief, CDs are not indestructible. The life of a CD depends on a number of factors that affect both the CD and the conditions under which the CD is written, or data is recorded onto it.


What is a CD?


CD is actually an acronym for the phrase compact disc. CDs are designed to be a form of portable media for data, music, photos and other file storage. For most newer computers, the CD drive has replaced the floppy disc drive. CDs have the advantage of being capable of storing much larger amounts of data than floppy discs. CDs are manufactured by a process comparable to that of producing vinyl discs--a blank disc with a hole in the center is treated and then imprinted with data, music or other media (for factory imprinted discs) or treated so that data can be written or burned onto them (for CD writable discs).


Factory-Pressed CDs


Factory-pressed CDs (for instance, software programs or music CDs) are impressed with the data or music at the factory. A protective coating is then applied to the finished product. This means that with proper handling, factory-written CDs should never suffer from data loss as a result,and should last indefinitely.; however, mistreatment of a factory-pressed CD can often damage the information or media pressed onto it. Of course, physically damaging or breaking the CD also usually renders the CD useless.


Read/Write CDs


CDs that are designed as read/write for consumer recording of files or media vary in life. The quality of the materials and production of the CD have a large bearing on how long the CD will survive. The quality of the CD burner as well as the speed of the recording (the optimal speed is neither too fast nor too slow) will also have a bearing on how long the CD lasts. The prevailing wisdom is that with reasonably good quality materials, a good quality recording of the files onto the CD and proper storage, a read/write CD can be expected to last several decades.


Rewritable CDs


Rewritable CDs are designed to allow the consumer to record data or files onto the CD more than once. These sort of CDs work much like cassette tapes or VCR tapes in that respect. While this can be convenient, it also means that rewritable CDs are much less stable than read/write CDs, which can only be recorded once. There have been instances of rewritable CDs becoming unusable after less than a year even under otherwise ideal conditions and with careful maintenance.


Other Factors


Other factors that affect the life of a CD are improper treatment after data or files have been burned onto a CD. Writing on the disc with a marker anywhere except the clear center section (where no data is written) can result in eventual erosion of the data side, even if the markings are made on the opposite side of the CD. Mishandling a CD can result in fingerprints, oil and debris on the data side of the disc, which can make the CD unreadable. Storing the CD improperly, either without a protective jacket or in extreme temperatures, can also result in damage to the CD.

Tags: data music, bearing long, burned onto, data files, data recorded, data side