Gigabyte (GB)
1 Gigabyte = 1,073,741,824 digital bytes / 1,000,000,000 decimal bytes, a unit of measure for data
Hard Error
a data error which is not able to be overcome when the disk is reread, it occurs repeatedly at the same location on the media, indicating a defect in the surface
Hardware
computer equipment (as opposed to the computer programs and software)
HC
High-speed CMOS)
HDA
Head Disk Assembly
HDD
Hard Disk Drive, magnetic storage device
Head crash
Occurs when a head and disk accidentally touch, thereby damages the media (and subsequently the data)
Head Landing Zone
Area on the media which is dedicated to head takeoff and landing, no data is recorded in this area
Head positioner
(see Actuator)
Host
the computer system that the drive is integrated into
Hot swap
replacement of hard drives, whilst computer is in operation with zero downtime
Host adapter
a plug-in board or circuitry on the motherboard that acts as the interface between a computer system bus and the disk drive
IC
Integrated Circuits. IC’s are arrays of electronic components such as transistors, diodes, resistors built from a single piece of semiconductor material. Huge numbers of components (millions) can be placed upon a single chip, the external connections being made via the pins on the IC package
IDE
Integrated Drive Electronics, a hardware interface that allows peripheral devices to be attached to a PC
IDE Controller
The controller translates commands from the computer into something that the hard drive understands
Interface
transmitters/receivers that establish links between various parts of a computer and facilitate the exchange of data between these components (e.g. IDE, EIDE, SCSI, and for notebooks PCMCIA). The way the drive and host communicate with each other. It is a standard defined by industry organisations
Interleave factor
the number of sectors that pass beneath the heads before the next sector arrives (a means to optimise performance of a drive)
Internal Transfer rate
the speed at which data is transferred to and from the media, reflected in millions of bits per second (Mbits/second)
Inside Diameter
smallest radius recording track on a platter
Inside Diameter
smallest radius recording track on a platter
I/O
Input/Output
ISA
Industry Standard Architecture
ISO
International Standards Organisation, sets standards for computer industry
ISO-9660
a data format designed by the ISO in 1984
