File Recovery Guide

Access time - The interval between the time a request for data is made by the system and the time the data is available from the drive.

Backup - A copy of a file, directory, or volume on a separate storage device from the original, for the purpose of Recovery in case the original is accidentally erased, damaged, or destroyed.

Disk - In general, any circular-shaped data-storage medium that stores data on the flat surface of the platter. The most common type of disk is the magnetic disk, which stores data as magnetic patterns in a metal coating. Magnetic disks come in two forms: floppy and hard.

File server - A computer that provides network stations with controlled access to shareable resources. The network operating system is loaded on the file server, and most shareable devices (disk subsystems, printers) are attached to it.

Hard disk - A type of storage medium that retains data as magnetic patterns on a rigid disk, usually made of a magnetic thin film deposited on an aluminum platter.

Head crash - Damage to a read/ write head and magnetic media, usually caused by sudden contact of the heads with the disk surface. Head crash also can be caused by dust and other contamination inside the HDA.

High-capacity drive - By industry conventions, typically a drive of 500 megabytes or more.

Interface - A hardware or software protocol, contained in the electronics of the disk controller and disk drive that manages the exchange of data between the drive and computer. The most common interfaces for small computer systems are AT (IDE) and SCSI.

Low-level formatting - The process of creating sectors on the disk surface so that the operating system can access the required areas for generating the file structure.

MTBF - Acronym for mean time between failures. Reliability rating indicating the expected failure rate of a product in power on hours (POH).

MTTR - Acronym for mean time to repair. The average time it takes to repair a drive that has failed for some reason.

Overhead - Command overhead refers to the processing time required by the controller, host adapter, or drive prior to the execution of a command.

RAM - Acronym for random access memory. An integrated circuit memory chip that allows information to be stored and retrieved by a microprocessor or controller.

Unformatted capacity - The total number of usable bytes on a disk, including the space that will be required later to record location, boundary definitions, and timing information.

Virus - A program written to do harm to a computer system. Viruses target files, the registry, or hardware.

Zip file - A Zip archive presented by Windows as a single file. The contents cannot be accessed without being decompressed.