Product guide

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Appendix C Glossary
Peripheral: Any device that is connected to the computer
system (i.e., printers, keyboard, plotters, etc.).
Peripheral Card: A printed circuit board that gives the computer
added capability, such as more memory or control of a new
device. A card plugs into one of the expansion slots located on
the system board.
Pin: Any of the leads on a device, such as an integrated circuit,
that plug into a socket and connect to a system.
PnP: Plug-and-Play. Refers to the ability of a computer system
to automatically configure expansion boards and other devices.
The technology developed by Microsoft and Intel that supports
plug-and-play installation. PnP is built into the Windows 95
operating system, but to use it, the computer's BIOS and
expansion boards must also support PnP. This is changing, as
IBM PC manufacturers adopt the new PnP specifications.
POST: Post On Self Test. Check-out procedures that the BIOS
runs automatically when the system is turned on. These
procedures verify that all computer hardware is functioning
properly. If the test detects problems, the computer displays
error codes before (or instead of) starting the operating system.
The error codes can help a service person determine what is
wrong with the computer.
Protocol: A set of formal rules describing how to transmit data,
especially across a network. Low level protocols define the
electrical and physical standards to be observed, bit- and byte-
ordering and the transmission and error detection and correction
of the bit stream. High level protocols deal with the data
formatting, including the syntax of messages, the terminal to
computer dialogue, character sets, sequencing of messages,
etc.
RAID: Redundant Array of Independent Drives. A technology
using a software or hardware controller with several disk drives to
allow varying degrees of either increased performance and/or data
integrity by combining several hard disk drives. RAID
configuration is typically used on a network file server. Levels of
redundancy or data security are dependent on the number of
drives in the array, as well as the way the data is stored across
the drives.
RAM: Random-Access Memory. The type of computer memory
that can be used to store information while a program is running.
RAM consists of a number of small integrated circuits that are
plugged into the system board or an external memory card.
Removable Storage: These devices allow you to store large
quantities of data. These devices far exceed the storage
capabilities of floppy disks. Read-Only Memory. The type of
computer memory that is used to permanently store the
information vital to computer operation, including some parts of
the operating system. ROM is permanent and the contents will
not be lost when power to the computer is turned off.
RISC: Reduced Instruction Set Chip. A processor whose design
is based on the rapid execution of a sequence of simple
instructions rather than on the provision of a large variety of
complex instructions. Also see, CISC.
ROM: Read Only Memory. The type of computer memory that is
used to permanently store the information vital to computer
operation, including some parts of the operating system. ROM is
permanent and the contents will not be lost when power to the
computer is turned off.
SCA: Single Connector Attachment. A non-standard type of SCSI
connector, used mostly by OEMs, which carries both power and
data on one 80-pin connector. SCA SCSI drives tend to be
cheaper but use with standard SCSI cables requires an adapter
and external termination.