hard disk drive definitions

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Hard Disk Drive Definitions


# | A | B | C | D | E | F | G | H | I | J | K | L | M

N | O | P | Q | R | S | T | U | V | W | X | Y | Z

Number

Currently no listings

A

A-cable

Access armAccess light

Active partitionActuator

ADSM

Allocation unitAnti vibration mount

AT attachment packet interfaceATAPI

B

BITBad sector

BlockBoot partition

BPBBus mastering

Byte

C

C:Cable selectCapacity

ClusterContiguous

Cross-linked filesCurrent drive

Cylinder

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D

Daisy chain

DASDData buffer

DDODeceleration time

DefragmentationDirect access

DiskDisk access time

Disk Drive OverlayDisk capacity

Disk controllerDisk crash

Disk densityDisk drive

Disk driverDisk duplexing

Disk optimizerDisk partition

Disk partition tableDisk platter

Disk thrashingDOS partition

DriveTrust DS

E

EBEIDE

ExabyteExternal storage

F

FAT

FAT12FAT16

FAT32FDISK

File size

Fixed diskFixed storage

Floating defectsFM

FNRFormat

Fsck

G

GB

Gigabyte

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H

Hard disk

Hard driveHead

Head positioningHead switching

High-level formatHousekeeping

I

IDCIDE

Index markIndex track

Interblock gapInterleave

Interrecord gap

IRG

J

Jump drive

K

Keyed

KilobitKilobyte

L

LBA

Low-level formatLzone

M

Mass storage

MasterMaster Boot Record

MB

MBRMedia

Megabit

Megabyte

MFM encoding

N

NON-DOS partitionNTFS

O


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P

Park

PartitionPermanent storage

PIOPK

PlatterPreformatted

Primary partition

Q


R

RAID

RAM disk

Redundant Array of Inexpensive DisksRemovable hard driveRibbon cable

Rigid diskRLL encoding

RPM

S

SATA

SCSI

Secondary storage device

Sector

Selector channelSelf-Monitoring Analysis and Reporting TechnologyServo motor

Settling timeSlave

Soft-sectored diskSource data disk

Step motorStorage

Storage devicesStore

Super blockSystem partition

T

TB

Terabyte

ThrashingTPI

Track

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U

UDMAUnpark

V

Voice coilVolume label

W

Winchester diskWpcomp

X


Y


Z

Zoned recording

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A-cable Back

Term used to describe a standard SCSI Cable.

Access arm Back

Also known as a head arm or actuator arm, the access arm is similar to an arm on arecord player and is found inside all computer hard disk drives. The access arm

allows the hard drive to move the read/write heads to the locations whereinformation needs to be read or written to. Below is a basic illustration of the inside

of a hard disk drive as well as an example of the access arm.

Access light Back

Also known as the activity light, the access light is a LED on the front of acomputer and/or disk drive that indicates when the computer or disk drive is being

used.

Active partition Back

Partition on a hard disk drive that is set as the bootable partition and generallycontains the operating system to be used on the computer. Only one partition on a

computer can be set as an active or bootable partition on a hard disk drive.

Actuator Back

An actuator is an electronic device controlled by a motor that moves the head arm towhere it needs to go. In the past the actuator within a hard disk drive was controlled

by a stepper motor. However, today the actuator is commonly controlled by a servomotor.

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ADSM Back

Short for ADSTAR Distributed Storage Management, ADSM is IBM's software that

helps clients manage storage devices.

Allocation unit Back

1. Group of reserved sectors on a computer hard disk drive.

2. When referring to memory, an allocation is a process preformed by the

computer that assigns a block of memory for a program to store its data or

information in.

Anti vibration mount Back

Drive bay mount that locks the hard drive or other 3.5-inch device in one place sothat the read/write heads and other mechanisms are protected from movement.

This mount is highly recommended when installing any 3.5-inch device in a 5.25-inchdrive bay in a computer.

ATAPI Back

Short for AT Attachment Packet Interface, ATAPI is an extension to ATA which

allows support for devices such as CD-ROM drives, Tape drives and other computerperipherals and not just hard disk drives. Before the release of ATA-4 or ATAPI-4,

ATAPI was a separate standard from ATA.

BIT Back

Sometimes abbreviated as b, a bit is short for Binary digIT and is a single unit ofinformation that can have a value of either ON or OFF.

When attempting to determine the amount of colors in a bit color depth, this can becalculated by: 2 to the power of the bit color. In other words, an 8-bit color would be

2^8 = 256 colors.

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Bad sector Back

Refers to a flaw with the hard disk drive disk or a manufacturer defect. When bad

sectors are encountered it is generally a defective disk or hard disk drive and it willneed to be replaced. Below is an example of what a sector is.

Block Back

1. When referring to a hard disk drive or other storage medium a block is a

segment of a large area that can be assigned to store data.

2. When referring to computer programming a block is a conditional statement

or loop in code. Below is an example of a conditional statement block.

if (conditional statement) {

print "Network Team";

}

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Partition Back

When referring to a computer hard disk drive, a partition is a segment of the hard

drive that is separated from other portions of the hard disk drive. Partitions helpenable users easily divide a computer hard disk drive into different drives and/or into

different portions for multiple operating systems to run on the same drive.

With older file allocation tables, such as FAT16, creating smaller partitions allows a

computer hard disk drive to run more efficiently and save more disk space. However,with new file allocation tables, such as FAT32, this is no longer the case.

There are various types of utilities used to create and manage partitions on hard diskdrives, one of the most commonly used and known utilities is Microsoft fdisk.

In addition to the utilities to create hard disk drive partitions, there are hundreds of

different types of partitions; below is a listing of some of these types of partitions aswell as a brief description about these partitions. While all of these partitions are

available, it is very likely that not all of these partitions will be listed in your partitionutility.

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Type of Partition Description

AIX Partition (Boot) Partition used with the AIX operating system.

Boot Partition As defined by Microsoft a boot partition is a partition that

contains the files required for a system startup. Also see:System Partition

BSD/OS Partition(OpenBSD)

Partition used with the BSD operating system.

DOS (12-bit, 16-bit)Partition

Partition used with older versions of MS-DOS.

DOS Extended Partition Partition that is extended from one or more of the originalMS-DOS partitions.

DRDOS (Hidden, Secured) Partition used with the DR. DOS operating system.

Extended Partition Partition that is extended from one or more of the primarypartitions.

Hibernation Partition Partition used with older hibernation programs.

HPFS Partition (OS/2 IFS) Partition used with IBM OS/2 and Microsoft NT 3.x

Linux (Linux native, Linux

swap, Linux extended,ext2fs)

Partition used with various variants of the Linux operating

systems.

MINIX Partition used with the MINIX operating system.

NON-DOS Partition When using Microsoft fdisk a NON-DOS partition indicates a

partition that is not native to the Microsoft operating

system. For example, this could be a Linux partition.NEC DOS Partition used with the old NEC DOS variant.

NEXTSTEP Partition used with the Nextstep operating system.

Novell Netware Partition used with the Novell Netware operating system.

NTFS Partition used with Microsoft Windows NT 4.x, Windows2000 and Windows XP.

Partition Magic

(PowerQuest)

Partition created using the Partition Magic utility by

PowerQuest.

PC-ARMOUR Partition created by the PC ARMOUR security utility. When

created this partition is commonly protected by apassword.

Primary In a Microsoft operating system the Primary Partitioncommonly refers to the main partition used for the

Microsoft operating system.

Solaris X86 Partition used with the Sun Solaris X86 platform operatingsystem.

System Partition As defined by Microsoft a system partition is a partition

that contains the system32 directory. Also see: BootPartition

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Tandy DOS Partition used with the old Tandy DOS variant.

UNIX System V (SCO, IRIX,

ISC, Unix, UnixWare, etc...)

Partition used with various UNIX operating systems.

VMWare (VMWare Swap) Partition used by VMWare.

XENIX (XENIX /usr) Partition used with the XENIX operating system.

BPB Back

Short for BIOS Pattern Block, BPB is the first section of the boot sector that

defines the settings and layout of a hard disk drive's partitions.

Bus mastering Back

Also sometimes referred to as BSIDE (Bus Mastering Integrated Drive Electronics) on

IDE, bus mastering is a method of transferring data without having to use the CPU.

Byte Back

Byte is data equal to either 7/8 bits depending if it needs error correction (parity). A

byte is spelled as byte and not bite.

C: Back

Drive letter of the first or primary hard disk drive installed in a PC or IBM compatible

computer.

Cable select Back

Often abbreviated as CS, cable select is a disk drive setting that will allow a cable

select compatible cable to determine what drive is the master and slave based offwhere the drives are connected to the cable. For cable select to work the both IDE /

EIDE drives must have their jumpers set to CS and be connected to a cable thatsupports cable select.

Users can easily identify if the flat ribbon cable supports cable select by examining

the cable for any of the below characteristics.

1. Cable is an 80-connector UltraATA cable.

2. Cable has master and slave printed on the cable or on the cable connectors.

Capacity Back

The maximum amount of data that a device such as a hard drive can hold. If and

when the device reaches its capacity it will no longer be able to hold more

information.

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Cluster Back

1. When referring to a hard disk drive, a cluster is a managed section by the

computer's Operating System that changes size depending upon the size of

the hard disk drive.

Because each file and even directories take up one or more clustersdepending on their size, earlier types of FAT potentially wasted hard disk

drive space. For example, if the cluster size was 8k and a 2k file is stored onthe computer, 6k of that cluster will go to waste.

This issue has been reduced with new versions of FAT have been made

available such as FAT32 that help resolve this issue.

2. A cluster may also be used to define a group of computers and/or servers

that share the work as one. Making one big computer instead of multiple

smaller computers.

Contiguous Back

1. In general, refers to an object that is adjacent to another object.

2. When referring to a computer hard disk drive, contiguous means sectors on a

disk that are by each other.

3. When referring to computer memory, contiguous means sections of memory

that are next to one another.

Cross-linked files Back

Cross-linked files are FAT entries that point to the same cluster. Cross-linked filesare generally created when the computer is improperly shut down or an application

abnormally aborts. Cross-linked files can be corrected using CHKDSK, or, morecommonly, Scandisk.

Current drive Back

Term used to describe the hard disk drive that is currently being accessed or used by

the operating system or software program.

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Cylinder Back

Two corresponding tracks on a fixed disk. Below is an example of a cylinder.

Daisy Chain Back

A number of hardware devices that are connected together with cables that resemblea chain. Generally, a SCSI device or devices are daisy chained; this allows for

multiple devices to work off of one card.

DASD Back

Short for Direct Access Storage Device, DASD is used as another name for a diskdrive.

Data buffer Back

An alternate, generally temporary, location to store data while being moved fromone location to another.

DDO Back

Short for Disk Drive Overlay, DDO is a TSR that loads onto sector two of the harddrive and is used for computers that do not support LBA mode. DDO allows the

computer to support and see larger than 520 MB.

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Deceleration Time Back

Term used to describe the amount of time for the hard drive head to slowdown as it

moves to a portion of the disk to retrieve information.

Defragmentation Back

Term used to describe the process of reorganizing a hard disk drive's data to help

increase the proficiency of accessing the data. Hard disk drives that are severelyfragmented will take longer to access the data because it is spread across the drive

and not located in a central area.

Direct access Back

1. Sometimes known as machine access or random access, direct access is a

term used to describe the ability of a computer to locate and retrieve dataimmediately from a storage device without having to start at the beginning

and read all information until the requested data is found.

For example, a hard disk drive is capable of directly accessing data. However,a tape drive must access all information before the requested data is

retrieved.

Disk Back

Hard or floppy round flat magnetic data storage platter that is capable of havinginformation saved to it. It is more appropriate to refer to a floppy disk as a floppy

diskette.

Disk access time Back

The total time required for the computer to process the data request from theprocessor and then retrieve the required data from a storage device.

DDO Back

Short for Disk Drive Overlay, DDO is a TSR that loads onto sector two of the hard

drive and is used for computers that do not support LBA mode. DDO allows thecomputer to support and see larger than 520 MB.

Disk capacity Back

The complete number of bytes that a disk drive is capable of holding.

Disk controller Back

Printed circuitry that contains the necessary instructions of diskette drives. The disk

controller is responsible for such drives as the hard disk drive, floppy disk drive, CD-

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ROM drive, etc...

Disk crash Back

Physical failure of a diskette or hard drive that is generally not recoverable.

Disk density Back

Also known as areal density, disk density is the measurement of the amount of dataa disk can hold. The disk density is generally measured by the tracks per inch and/or

bits per inch. A good example of disk density is high-density floppy diskettes that arecapable of holding more information than a low density diskette.

Disk drive Back

Physical drive capable of holding information and/or retrieving information. A goodexample of a disk drive is the computer floppy disk drive.

Disk driver Back

Device driver that allows a specific disk drive to communicate with the remainder ofthe computer. A good example of this type of driver is a floppy disk driver.

Disk duplexing Back

Method of how information is written to the hard disk drive. With disk duplexing,

when information is needed to be written to a hard disk drive, instead of only one

disk drive, it is copied to both drives, generally on different disk controllers.

Disk optimizer Back

Also known as disk compression, a disk optimizer is a software program designed to

organize data and/or compress data allowing the disk drive to contain the maximumamount of information as possible.

A good example of a disk compression software program is a Microsoft Windowsutility known as double space.

With today's large hard disk drives, disk compression utilities are no longer used and

no longer recommended. Generally, a disk compression utility should be used onhard disk drives of 1 gig and smaller.

The Microsoft Windows utility defrag can be considered a disk optimizer and is still

commonly used and recommended even on large hard disk drives.

Disk partition Back

Portion of a disk capable of holding data. This allows for a hard disk drive to be splitinto multiple segments allowing the computer to have multiple disk drives.

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Disk partition table Back

Permanent structure which indicates to the operating system or boot record how

information on a hard disk drive is to be laid out.

Disk platter Back

Magnetic metal or ceramic disk located inside the computer hard disk drive that

holds the actual data. Below is an illustration of a disk platter.

Thrashing Back

When referring to a computer, thrashing or disk thrashing is a term used to

describe when the hard disk drive is being overworked by moving informationbetween the system memory and virtual memory excessively. Thrashing is often

caused when the system does not have enough memory, the system swap file is notproperly configured, and/or too much is running on the computer and it has low

system resources.

When thrashing occurs, a user will notice the computer hard disk drive always

working and a decrease in system performance. Thrashing is bad on a hard diskdrive because of the amount of work the hard disk drive has to do and if is left

unfixed will likely cause an early failure of the hard disk drive.

To resolve hard disk drive thrashing, a user can do any of the below.

1. Increase the amount of RAM in the computer.

2. Decrease the amount of programs being run on the computer.

3. Adjust the size of the swap file.

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Partition Back

When referring to a computer hard disk drive, a partition is a segment of the harddrive that is separated from other portions of the hard disk drive. Partitions help

enable users easily divide a computer hard disk drive into different drives and/or intodifferent portions for multiple operating systems to run on the same drive.

With older file allocation tables, such as FAT16, creating smaller partitions allows acomputer hard disk drive to run more efficiently and save more disk space. However,

with new file allocation tables, such as FAT32, this is no longer the case.

There are various types of utilities used to create and manage partitions on hard disk

drives, one of the most commonly used and known utilities is Microsoft fdisk.

DriveTrust Back

A hard disk drive technology developed by Seagate that was first widely used withDVR's and later introduced to personal computers with the Seagate Momentus 5400

FDE.2. This technology encrypts the data on the hard disk drive and only allows thatdata to be read by the device or computer the drive is installed in.

Because this new innovation is built onto the hard disk drive computers can havethese drives installed with no additional software or patches. In addition the drives

have a feature that allow them to be instantly erased, which helps prevent any

sensitive data being read when the drive is sold or used in another computer.

DS Back

Short for Drive Select, DS is a jumper setting found on disk drives that is similar to

the more commonly used master jumper setting. When a disk drive such as acomputer hard disk drive has its jumper set to DS this tells the computer that it's the

only drive connected to the cable or should be used as the primary drive (masterdrive) on the cable.

EB

1. Short for Exabyte, an EB is 1018 or 1,000,000,000,000,000,000 bytes.

2. Exabyte is also a computer company.

EIDE Back

Short for Enhanced IDE, EIDE is the next generation of IDE interface that wasdeveloped by Western Digital and an interface commonly used on IBM compatible

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computers. EIDE supports data rates from 4 and 16.6 MBps. In addition to beingfaster than IDE drives, EIDE supports drives up to 8.4GB.

Supports faster PIO modes 3 and 4 as well as multiword DMA modes 1 and 2. ATA-2

also adds additional support for LBA drives which allows support for drives largerthan 528 MB. EIDE is also referred to as ATA-2, Fast ATA or Fast IDE.

External storage Back

Type of storage that is not part of the computer's memory. Examples of externalstorage are floppy disk drives, hard disk drives, tape drives, etc.

FATBack

Short for File Allocation Table, FAT is a method used by Microsoft operating

systems to keep track of the contents of a disk; the table is a chart of numbers thatcorrespond to cluster addresses on the hard drive.

FAT12: The oldest type of File Allocation Table that uses 12-bit binary system. Ahard disk drive formatted using FAT12 can use a maximum of approximately

16,736,256 volume size and today is no longer used. If your computer is runningWindows 95 or above and your FAT within FDISK is being displayed as FAT12 it is

likely that your hard disk drive is corrupted, bad or has a computer virus.

FAT16: FAT utilizing a 16-bit binary system. Commonly found with Windows 3.x

through Windows 95. FAT16, while becoming obsolete by FAT32, is still commonlyfound.

FAT32: Enhanced File Allocation Table utilizing a 28-bit binary system, first used inWindows 95 OSR2 and more so in Windows 98, that saves disk space by using 4k

Cluster. See FAT32 Page for extended information about FAT32.

NTFS BACK

Short for New Technology File System, NTFS is a file organizational system thatstores and accesses information located on Microsoft Windows NT, Windows 2000,

Windows XP operating system. NTFS offers better methods of data protection and filerecovery than previous versions of FAT.

VFAT BACK

New implementation of FAT code included with Microsoft Windows 95 that allows file

and directory names up to 255 characters in length.

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HPFS BACK

Short for High-Performance File System, HPFS is a file system first introduced

with IBM OS/2 1.2. HPFS is available on OS/2 1.2 and above as well as withMicrosoft Windows NT 3.0. HPFS supports long file names and large hard drives

when compared to FAT.

HPFS supports a maximum of 64 GBytes

HPFS386 is a 32-bit Version of HPFS used with IBM LAN Server Advanced andWarp Server Advanced.

Overall, HPFS is not commonly found or used with today's computers and servers.

FDISK BACK

FDISK (pronounced eff-disk) is an external MS-DOS utility that is used to configure

the fixed disk. The FDISK program allows you to delete, create, and partition

different portions of the hard drive. FDISK is also used in Windows 95, Windows 98and Windows ME; however, after the release of FAT32, there are different versions of

FDISK available.

File size BACK

The measure of space a file takes on a storage medium such as a computer harddisk drive. File sizes can be measured in bytes (B), kilobytes (KB), megabytes (MB),

gigabytes (GB), terabytes (TB), and beyond.

Fixed disk BACK

Term commonly used with Hard disk drives because most hard drives are commonly

designed to not be easily removed from the computer.

Fixed storage BACK

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Medium not easily removed, for example, a hard disk drive. Fixed storage is often representedon a computer network as a drive capable of storing data.

Floating defects BACK

Type of physical defect encountered on a hard disk drive where the disk drive heads become outof alignment causing random read/write errors.

FM BACK

1. Short for Frequency Modulation, FM encoding is a method of recording data

to a floppy disk and/or hard disk drive platter. This method of encoding is nolonger used today and has been replaced with MFM.

2. When referring to the radio or an audio signal , FM is short for Frequency

Modulation. FM is a method of transmitting a signal of greater quality atranges of 80 MHz to 108 MHz at a shorter distance when compared to AM.

FNR BACK

Short for Format and Restore, FNR is a term often used by technicians to refer to

proceeding with a format and restore of a computer system.

Format BACK

1.The overall layout of a document. For example, the formatting of text onmany English documents are aligned to the left of a page.

2. Format is also a MS-DOS command that prepares a blank diskette or hard

disk by first formatting the disk to hold data.

Fsck BACK

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1. Short for File System Check, fsck is a program run on Linux, Unix and their

variants that checks the file system for any errors. For users who are familiar

with Microsoft Windows, this command is similar to Microsoft's scandiskcommand.

GB BACK

Short for Gigabyte, GB is equal to 1,073,741,824 bytes, however the IEC defines a

GB equal to 109 or 1,000,000,000 bytes. Therefore, a GB could be either of thesevalues; many hard disk drive manufacturers and computer manufacturers will define

what they consider a Gigabyte to equal in the fine print.

A Gb, or Gigabit, is different from a GB

Hard disk BACK

Rigid circular disk located inside a computer hard disk drive. The term hard disk isoften used as an abbreviation to hard disk drive.

Hard drive BACK

Computer's main storage media device, also called a hard disk drive or abbreviated

as HD or HDD. The hard drive was first introduced on September 13, 1956 andconsists of one or more hard disks inside of air sealed casing. Most hard drives are

permanently stored in an internal drive bay at the front of the computer and areconnected with one ATA / SCSI cable and power cable. Below is an illustration of the

inside of a hard disk drive.

Head BACK

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Device found on the arm of a hard disk drive that is used to read data from the harddisk drive's disk platter.

Head positioning BACK

Action performed by a computer hard disk drive that moves the hard disk drive head

into its proper position and verifies nothing is malfunctioning with the head arm.

Park BACK

When referring to a computer hard disk drive, park refers to a process of moving a

computer hard disk drive head away from the disk platters to prevent the head frommistakenly damaging the disk platter when the computer or hard disk drive is being

moved.

In the past, older hard disk drives and operating systems required the user to

manually park and unpark the hard disk drive using a software utility or program.Today, however, hard disk drives automatically park and unpark.

Head switching BACK

Action taken by the hard disk drive head that moves the current action being

performed on one read / write head to another.

High-level format BACK

Method of formatting a hard disk drive that initializes portions of the hard disk driveand creates important file system areas on the disk. A good example of a high-level

format is using the format command in MS-DOS.

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A high-level format is commonly done if a user wishes to erase the hard disk driveand reinstall the operating system back onto the hard disk drive. If errors are

present on the hard disk drive, or a high-level format is unable to be completed, a

low-level format may need to be done first.

Housekeeping BACK

When referring to computers, housekeeping is a term used to describe the

optimization of a hard disk drive. Housekeeping commonly involves removing old or

unused files, removing programs no longer being used, backing up data, and/orrunning disk utilities such as a scandisk, defrag, or a virus scan. Housekeeping is

meant as a way to help keep the computer organized and running properly and

should be performed at least once a year.

IDC BACK

Short for Insulation Displacement Contact or Insulation Displacement

Connector, IDC is a type of connector found at the end of many cables. Forexample, an IDE disk drive or floppy disk drive cables have IDCs at the ends of the

ribbon cable. In the below illustration you can see three Insulated Displacement

Connectors on the floppy cable.

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IDE BACK

1. Short for Integrated Drive Electronics or IBM Disc Electronics, IDE is

more commonly known as ATA and is a standard interface for IBM compatiblehard drives. IDE is different from the Small Computer Systems Interface

(SCSI) and Enhanced Small Device Interface (ESDI) because its controllersare on each drive, meaning the drive can connect directly to the motherboard

or controller. IDE and its updated successor, Enhanced IDE (EIDE), are themost common drive interfaces found in IBM compatible computers today.

Below is a picture of the actual IDE connector and cable.

2. Short for Integrated Development Environment, IDE also sometimes

referred to as IDLE, IDEs are visual tools that allow programmers to develop

programs better. Commonly, an IDE may have a compiler, debugger, texteditor, and other integrated tools. Smalltalk was the first programming

language to have a first true IDE.

Index mark BACK

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Also known as the index track, the index mark is a mark used to indicate the starting point of atrack on a hard disk drive. This mark is commonly a small hole, gap or magnetic strip. The indexmark allows a hard disk drive head to move quickly to various portions of the hard disk drive.

Interrecord gap BACK

Also known as an Interblock gap and abbreviated as IBG or IRG, an Interrecord gap is abreak between data records on hard drive and magnetic tape that serves as a safety margin fordata overwrites. Interrecord gaps are also used as a marker for the end of data.

Interleave BACK

1. When referring to a computer hard disk drive, interleaving is a method of

making the read of data more efficient. Interleaving is a method of organizing

the sectors on a computer hard disk drive, allowing data to be arranged sothe read/write head can access information easier, making data read off the

hard disk drive faster.

Types of interleaving:

One-to-one = Sectors are placed on a trackTwo-to-one = Sectors are spread out by other sectors.

2. When referring to computer memory, interleaved memory is system memorydivided into two or more sections. This allows for memory to be accessed

faster because each section of memory is capable of being utilized at once.


Also known as an Interblock gap and abbreviated as IBG or IRG, an Interrecordgap is a break between data records on hard drive and magnetic tape that serves as

a safety margin for data overwrites. Interrecord gaps are also used as a marker forthe end of data.


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Also known as an Interblock gap and abbreviated as IBG or IRG, an Interrecordgap is a break between data records on hard drive and magnetic tape that serves as

a safety margin for data overwrites. Interrecord gaps are also used as a marker forthe end of data.

Jump Drive Or USB flash drive BACK

Also known as a USB flash drive, ajump drive is a portable memory disk, a jump

drive is a small device (about the size of your index finger) that connects to acomputer's USB port and often is capable of storing 256MB, 512MB, or more. Jump

drives are used by users who need an easy and small way to transfer or storeinformation from their computer.

Key BACK

1. When referring to a computer keyboard, a key is a single button on the

keyboard. Letters, numbers, functions, and symbols are all represented on

keys.

2. A key is also a tool used to lock and unlock a computer, computer drive or

other computer related device. If you have lost the key to your computer

device, Please contact the manufacturer of the product that is locked.

3. When referring to the computer Microsoft Windows registry, a registry key,

or key for short, is a term used to identify an item in the registry, such as

HKEY_LOCAL_MACHINE.

4. The term key or keyed may also be used to describe a cable with physical

dimensions that causes a cable such as a ribbon cable to be connected only

one direction. In some rare cases this may prevent a cable from beingproperly connected to a drive. For example, the manufacturer of a floppy disk

drive may have keyed their connection differently than the cablemanufacturer has. In this situation, the user may either be required to

purchase a different brand of cable or floppy drive, or modify the key on thecable.

Kilobit BACK

A kilobit, or Kb, is equal to 1,000 bits.

When the b is uppercase (KB), this refers to a kilobyte.

Kilobyte BACK

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Abbreviated as K or KB, a Kilobyte is equal to 1,024 bytes; however, the IECdefines that one KB is equal to 1,000 bytes. Therefore, a KB could really equal either

of these values.

With a lowercase b (Kb), this refers to a kilobit.

LBA BACK

Short for Large Block Addressing, LBA allows a PC computer to access hard diskdrives larger than 528MB.

Low-level format BACK

An initial formatting of a hard drive that initializes the physical tracks on the surface

or the internal disks. The drive manufacturer usually performs a low-level formaton the hard disk drive before it is released and is not something a user needs to do

once they've purchased the drive.

If a high-level format (i.e. running the MS-DOS format command) is unable to becompleted on a hard disk drive and/or you're looking for information about how to do

a low-level format because of a MBR virus or being unable to delete partitions, a

debug routine can be performed on the computer that is often referred to as a low-level format.

Lzone BACK

Short for landing zone, lzone is setting used to specify the landing zone of the heads

on a computer hard disk drive. Today, with new computers, the lzone is no longerrequired as most computer hard disk drives autopark.

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Mass storage BACK

Term used to describe a location with large quantities of data.

Master BACK

A setting commonly adjusted using a jumper found on a computer peripheral, such

as a hard disk drive or CD-ROM drive. This setting sets the drive to be the primarydrive and allows for multiple devices to be connected to a single

connection. Computers can only have one master per channel, this means there canonly be one master drive on a single IDE/EIDE cable.

Mb / MB BACK

1. Mb is short for megabit and is 1,000,000 bits, or 106, Mb commonly usually

expresses the rate at which data is transferred, for example, "10/100 Mbps"

represents 10 or 100 megabits per second, the common speed of a standardnetwork card.

2. Also abbreviated as meg, MB is short for megabyte. A MB is a common

measurement used with computer storage media. A Megabyte is equal to1,048,576 bytes; however, the IEC defines that one MB is equal to 1,000,000

bytes, or 106. Therefore, a MB could really equal either of these values.

3. mb or MB is also short for Motherboard.

Mebibit BACK

A mebibit, or Mib, is 220 and is equal to 1,048,576 bits.

Mebibyte BACK

A mebibyte, or MiB, is 220 and is equal to 1,048,576 Bytes.

MBR BACK

Short for Master Boot Record, MBRis also sometimes referred to as the master

boot block and is the first sector of the computer hard disk drive used to determinefrom which partition a computer will boot. The MBR tells the computer where to find

and how to load the operating system. It also tells the computer how the hard driveis organized and provides information about the drive's partitions.

The master boot record is located on the first sector of the hard drive; it's the firstprogram the computer runs after performing a memory check and looking for a

bootable disk (if set in CMOS). The MBR is also susceptible to boot sector virusesthat can corrupt or delete the MBR, which can leave the hard drive unusable and

prevent the computer from booting up. A well-known MBR virus is the Monkey Virus.

Media BACK

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Term used to describe a type of computer storage. For example, a floppy diskette isa type of media used to store data.

MFM encoding BACK

Short for Modified Frequency Modification encoding, MFM encoding is a method

of how a disk controller records information onto a floppy disk and/or hard disk driveplatter that replaced FM.

NTFS BACK

Short for New Technology File System, NTFS is a file organizational system that

stores and accesses information located on Microsoft Windows NT, Windows 2000,Windows XP operating system. NTFS offers better methods of data protection and file

recovery than previous versions of FAT.

Park BACK

When referring to a computer hard disk drive, park refers to a process of moving acomputer hard disk drive head away from the disk platters to prevent the head from

mistakenly damaging the disk platter when the computer or hard disk drive is beingmoved.

In the past, older hard disk drives and operating systems required the user tomanually park and unpark the hard disk drive using a software utility or program.

Today, however, hard disk drives automatically park and unpark.

Permanent storage BACK

Type of computer storage that keeps the data or its contents regardless if the power

is turned off or if the storage device is moved to another computer. The mostcommonly used permanent storage is the computer hard disk drive.

PIO BACK

PIO, or Programmed Input/Output, is a method of transferring data from a device

to another device, utilizing the computer processor and not the memory or DMA.Because PIO modes utilize the computer processor, using PIO is slower than DMA.

PIO Mode Max Transfer Rate ATA Standard

Mode 0 3.3 MB ATA

Mode 1 5.2 MB ATA

Mode 2 8.3 MB ATA

Mode 3 11.1 MB ATA-2

Mode 4 16.6 MB ATA-2

Note: There are no plans, and likely will never be plans, for a PIO Mode 5 (or

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anything beyond Mode 4), although some computer and hardware manufacturershave advertised computer or hardware with acceptance to PIO Mode 5.

PK BACK

1. Short forjumper park, PK is a disk drive setting that is similar to the more

common slave setting found on most drives. When a drive is set to thissetting it is configured as the secondary drive (slave drive).

Platter BACK

An aluminum, glass, or ceramic disk that is coated in a magnetic media that islocated within a hard disk drive and used to permanently store all your computer's

data. When the computer is turned on, these platters will begin to rotate at so manyrotations per minute (RPM). This rate varies depending upon the model of hard drive

you have; an example of how fast a hard drive may spin is 7200 RPM. As the diskplatters are rotating, the read/write head accesses information on one of the

platters. It is not uncommon for a computer hard disk drive to have multiple platters.To help store and retrieve the data from the platter, data is stored in tracks, sectors

and cylinders on each platter.

Preformatted BACK

Computer diskette, tape, hard disk drive, or other medium that has already been

formatted and does not require the user to format the disk before using it.

RAID BACK

Short for Redundant Array of Inexpensive Disks, RAID is an assortment of hard

disk drives connected and setup in ways to help protect and/or speed up the

performance of a computer's disk storage. RAID is commonly used on servers andhigh performance computers

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RAM disk BACK

1. Also known as a RAM drive, a RAM disk is a software-generated disk drive

that stores information in the computer memory instead of on a physical disk

drive. Because information is stored and accessed directly from the computermemory, RAM disk drives are faster; however, they are much more expensive

than a standard hard disk drive.

2. RamDisk is also a software product by SuperSpeed that enables Microsoft

Windows computers to increase the overall performance of the computer by

creating a virtual drive in memory.3.

Removable hard drive BACK

A computer hard drive that has been placed within a plastic or metal cartridge that

enables it to be removed easily and placed into other computers with similarremovable bays.

Ribbon cable BACK

A thin cable that resembles a car seat belt or duct tape. These cables are commonly

the data cables used for devices such as a CD-ROM drive or a Hard disk drive. It iscommon for most ribbon cables found within a computer to contain a dotted stripe or

line along one side of the cable, this line indicates which edge of the cable is pin one,helping the user connect the cable properly.

In addition to one edge of the cable being marked, most ribbon cables used today

are also keyed, making it possible to only connect the cable one way.

Rigid disk BACK

The name of a disk or disc that is not flimsy like tape. A good example of rigid disks

are the disk platters found in a hard disk drive; floppy diskettes, CDs, and Zipdiskettes are also all considered rigid disks.

RLL encoding BACK

Short for Run-Length Limited encoding, RLL encoding is a method of storing

information on computer hard disk drives, floppy disk drives, CDs, DVD, and Blu-Raythat was originally invented by IBM. This method of storage is carried out by

hardware in the disk controller and is less prevalent than the modified frequency

modulation (MFM) encoding scheme.

ARLL, or Advanced Run-Length Limited, is a more advanced version of RLL.

RPM BACK

Short for Revolutions Per Minute, RPM is used to help determine the access timeon computer hard disk drives. RPM is a measurement of how many complete

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revolutions a computer's hard disk drive makes in a single minute. The higher theRPM, the faster the data will be accessed; for example, if you were comparing two

hard disk drives, one with 5400 RPM and another with 7200 RPM, the hard disk drivewith a 7200 RPM will be capable of accessing data much faster than the 5400 RPM

drive. However, it is also important to note that a 5400 RPM drive will be muchcheaper than a 7200 RPM drive.

While it may not be a noticeable speed difference when loading small files, the RPM

of a hard disk drive can make a dramatic difference when loading large files and/or

several hundred or thousand files. We always recommend users get at least a 7200RPM drive.

SATA BACK

Short for SerialATA, SATA 1.0 was first released in August 2001 and is a

replacement for the Parallel ATA interface used in IBM compatible computers.SerialATA is capable of delivering 1.5Gbps (150MBps) of performance to each drive

within a disk array, offers backwards compatibility for existing ATA and ATAPI

devices, and offers a thin, small cable solution as seen in the below picture. Thiscable helps make a much easier cable routing and offers better airflow in thecomputer when compared to the earlier ribbon cables used with ATA drives.

The official SerialATA web page can be located at http://www.serialata.org

SCSI BACK

Short for Small Computer System Interface, SCSI, pronounced as "Scuzzy", is thesecond most commonly used interface for disk drives. Unlike competing standards,

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SCSI is capable of supporting eight devices, or sixteen devices with Wide SCSI.

SCSI-1 is the original SCSI standard developed back in 1986 as ANSI X3.131-1986.

SCSI-1 is capable of transferring up to eight bits a second.

SCSI-2, approved in 1990, added new features such as Fast and Wide SCSI, and

support for additional devices.

SCSI-3 was approved in 1996 as ANSI X3.270-1996.

SCSI, pronounced as Scuz-zee, is a standard for parallel interfaces that transfersinformation at a rate of eight bits per second and faster, which is faster than the

average parallel interface. SCSI-2 and above supports up to seven peripheraldevices, such as a hard drive, CD-ROM, and scanner, that can attach to a single

SCSI port on a system's bus. SCSI ports were designed for Apple Macintosh and Unixcomputers, but also can be used with PCs.

Secondary storage device BACK

A storage medium that holds information until it is deleted or overwritten.

Sector BACK

A division of a storage medium such as a hard drive or diskette. Diskettes or hard

drive platters are divided into wedge shaped sections that segment the circulartracks into small arcs such as if you were to cut a pie into a section, each section is

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one arc. Each arc is a sector that typically holds 512 bytes of data. All of the arcswithin a given wedge are given the same sector number for interleaving purposes, so

the term sector may refer to the entire single arc. The size of sectors can becustomized to maximize the storage area. For example, if a user stores smaller files,

decreasing the sector size allows more files to fill the space without any leftoverroom.

Selector channel BACK

A high-speed input / output (I/O) channel that links a peripheral device, such as ahard drive or CD-ROM, to the computer.

S.M.A.R.T. BACK

1. Short for Self-Monitoring Analysis and Reporting Technology, S.M.A.R.T,

or SMART, is a diagnostic method originally developed by IBM to test hard

disk drives and was introduced with the ATA-3 specification.

2. When referring to software, smart is also known as intelligence and is an

ability of a program to function with little or no human interaction.

Servo motor BACK

When referring to a computer hard disk drive, a servo motor is a new type of

actuator motor that replaces the old step motor found in computer hard disk drives.

Settling time

The time it takes a hard disk drive's read / write head to move to a position. This

time is commonly factored into the hard disk drive's seek time.

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Slave BACK

1. Computer or peripheral device that operates under the control of another

computer peripheral.

2. A setting commonly adjusted using a jumper found on a computer peripheral,

such as a hard disk drive. This setting sets the drive to be the secondary driveand allows for multiple devices to be connected to a single connection.

Soft-sectored disk BACK

A disk that has had its sectors mapped with a software program instead of a physicalseparation created on the disk.

Source data disk BACK

Term could also be source data disc, source data diskette, or source data drive,

the source data disk is a diskette, disc, or drive from which data will be copied to analternate diskette or disc. For example, when copying a floppy diskette to another

floppy diskette the source data diskette is where the information is being copied fromand the destination data diskette is where the information is being copied to.

Step motor BACK

An actuator motor that moves in small, consistent increments. The stepper motor is

used in older computer hard disk drives to move the actuator arm by reacting tostepper pulses. New hard disks drives, however, utilize a servo motor.

Storage BACK

Term used to describe a location where information can be held for later use. A

computer commonly has two types of storage: internal and external. An internalstorage is a device such as a hard disk drive, where an external storage may be a

device such as a tape drive that utilizes removable diskettes to store information.

Storage devices BACK

A storage device is a hardware device designed to store information. There are twotypes of storage devices used in computers; a 'primary storage' device and a

'secondary storage' device.

Store BACK

Term used to describe the process of saving information to be used later. Commonly,when a user stores information, he or she is storing the information on a disk drive

such as a hard disk drive or a floppy disk drive.

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moved.

In the past, older hard disk drives and operating systems required the user to

manually park and unpark the hard disk drive using a software utility or program.

Today, however, hard disk drives automatically park and unpark.

Voice coil BACK

1. When referring to a computer hard drive, a voice coil is a type of motor used

to move the access arm within a hard disk drive.

2. When referring to an audio speaker, a voice coil is a wire that is adjusted witha magnetic field to adjust the intensity of the audio signal.

Volume label BACK

With IBM compatible computers a volume label is a unique name commonly assigned

by the user to a storage medium. For example, a user is capable of changing thelabel on a floppy disk to describe what may be on a diskette.

Winchester disk BACK

Named after the .30-caliber Winchester rifle, Winchester disk drive is a hard disk

drive developed by IBM that had two 30MB capacity and offered a 30 millisecond(ms) access time.

Wpcomp BACK

1. Short for Write Pre-Comp, wpcomp is a setting used with computer hard

disk drives that specifies when adjustments are to be made when writing

inside tracks of a hard disk drive platter.

2. Wpcomp can also be short for Word Processing Competency.

Zoned recording BACK

Method hard disk drive manufacturers use to increase the available hard disk drive

space by increasing the amount of sectors per track. This enables outer tracks tohave more sectors than inner tracks. In the past, a hard disk drive had the same

amount of sectors on each of its tracks.

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hard disk drive definitions

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