IDE (Integrated Drive Electronics)
A type of drive where the interface controller electronics are incorporated into the design of the hard drive rather than as a separate controller.
Index Pulse Signal
A digital pulse signal indicating the beginning of a disk revolution. An embedded servo pattern or other prerecorded information is present on the disk following index.
Initiator
A device in control of the SCSI bus that sends commands to a target. Most SCSI devices have a fixed role as an initiator or a target; however, some devices can assume both roles.
Initialization
See low-level formatting.
Input
The incoming data that the computer processes, such as commands issued by the user.
Input/output (I/O)
An operation or device that allows input and output.
Interface
A hardware or software protocol that handles the exchange of data between the device and the computer; the most common ones are AT (also known as IDE) and SCSI. (See AT and SCSI.)
Interface controller
The chip or circuit that translates computer data and commands into a form suitable for use by the hard drive and controls the transfer of data between the buffer and the host. (See disk controller and disk drive controller.)
Interleave
The arrangement of sectors on a track.
Interrupt
A signal sent by a subsystem to the CPU that signifies a process has either completed or could not be completed.
ISA
Industry Standard Architecture. The standard 16-bit AT bus designed by IBM for the PC/AT system. ISA was the only industry standard bus for PCs until the recent release of MCA (MicroChannel Architecture), EISA (Extended Industry Standard Architecture), and PCI (Peripheral Component Interconnect).
