Specifications
Glossary
39
interleaved memory The process of alternating
access between two banks of memory to overlap
accesses, thus speeding up data retrieval. Systems
that require only one memory module per bank to
operate can work more quickly when two are
installed if the system supports interleaved memory.
Inter-Module Bus (IMB) A proprietary high-
speed bus used by the Broadcom ServerWorks
chipsets. It runs at various speeds, depending on
the chipset.
internal command In DOS, a command con-
tained in
COMMAND.COM so that no other file must be
loaded to perform the command.
DIR and COPY are
two examples of internal commands. In Windows,
a command contained in
CMD.EXE.
internal device A peripheral device installed
inside the main system case in either an expansion
slot or a drive bay.
internal drive A disk or tape drive mounted
inside one of a computer’s disk drive bays (or a
hard disk card, which is installed in one of the
computer’s slots).
Internet A computer network that joins many
government, university, and private computers
together. The Internet traces its origins to a net-
work set up in 1969 by the Department of Defense.
You can connect to the Internet through many
online services, such as CompuServe and America
Online, or you can connect through local Internet
service providers (ISPs). Internet computers use the
TCP/IP communications protocol. Several million
hosts exist on the Internet; a host is a mainframe,
mini, or workstation that directly supports the
Internet protocol (the IP in TCP/IP).
Internet Corporation for Assigned Names
and Numbers (ICANN) The non-profit organi-
zation having the responsibility for IP address and
domain name assignments on the Internet.
Internet Explorer (IE) Microsoft’s line of web
browsers for Windows and Macintosh computers.
Most websites are optimized to display best on sys-
tems running recent versions of IE.
interpreter A program for a high-level language
that translates and executes the program at the
same time. The program statements that are inter-
preted remain in their original source language, the
way the programmer wrote them—that is, the pro-
gram does not need to be compiled before execu-
tion. Interpreted programs run more slowly than
compiled programs and always must be run with
the interpreter loaded in memory.
interrupt A suspension of a process, such as the
execution of a computer program, caused by an
event external to that process and performed in
such a way that the process can be resumed. An
interrupt can be caused by internal or external con-
ditions, such as a signal indicating that a device or
program has completed a transfer of data. Hardware
interrupts (also called IRQs) are used by devices,
whereas software interrupts are used by programs.
See also IRQ.
interrupt vector A pointer in a table that gives
the location of a set of instructions the computer
should execute when a particular interrupt occurs.
IO.SYS One of the DOS/Windows 9x system files
required to boot the machine. The first file loaded
from disk during the boot, it contains extensions to
the ROM BIOS.
IP address An identifier for a computer or
device on a TCP/IP network. The format of an IP
address is a 32-bit numeric address written as four
numbers separated by periods, in which each num-
ber can be 0–255. The TCP/IP protocol routes mes-
sages based on the IP address of the destination.
IPv6 A new version of the IP protocol that
expands the range of IP addresses from 32 bits to
128 bits, which relieves the strain on the current
universe of IP addresses. IPv6 is backward compati-
ble with IPv4 to allow its gradual adoption.
IPX (internetwork packet exchange) Novell
NetWare’s native LAN communications protocol
(primarily in versions 4.x and earlier) used to move
data between server and/or workstation programs
running on different network nodes. IPX packets
are encapsulated and carried by the packets used in
Ethernet and the similar frames used in Token-Ring
networks.
IrDA An infrared communications standard
established by the Infrared Data Association in
1993. IrDA is currently used primarily for data
transfer between portable computers or to allow
portable computers to print to a printer with an
IrDA port.
Appendix A
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