Physical Damage
A wide variety of failures can cause physical damage to storage media. CD-ROMs can have their metallic substrate or dye layer scratched off; hard disks can suffer any of several mechanical failures, such as head crashes and failed motors; tapes can simply break. Physical damage always causes at least some data loss, and in many cases the logical structures of the file system are damaged as well. Any logical damage must be dealt with before files can be salvaged from the failed media.
Most physical damage cannot be repaired by end users. For example, opening a hard disk drive in a normal environment can allow airborne dust to settle on the platter and become caught between the platter and the read/write head, causing new head crashes that further damage the platter and thus compromise the recovery process. Furthermore, end users generally do not have the hardware or technical expertise required to make these repairs. Consequently, data recovery companies are often employed to salvage important data.
Read more about this topic: Data Recovery
Famous quotes containing the words physical and/or damage:
“I became the Incredible Shrinking Mother the year they started junior high. If our relationship today depended on physical clout, I would have about the same influence with them that the republic of Liechtenstein has on world politics.”
—Mary Kay Blakely (20th century)
“There is such a thing as food and such a thing as poison. But the damage done by those who pass off poison as food is far less than that done by those who generation after generation convince people that food is poison.”
—Paul Goodman (1911–1972)