Glossary

account

See login account.

active window

The only window that recognizes input (activity) from the keyboard and mouse; only one window is active at a time.

address dial

See SCSI address dial.

administrator

The person who can use the most privileged account, root. The administrator must have a personal login account for daily use, but to correct serious system problems, the administrator logs in to the root account to change system information using the graphical tools or using the IRIX shell.

The administrator has all the capabilities of a privileged user, plus the capability to change information in the root account (such as the password) and to log in to an IRIX shell as root. Because there is only one root account, there is only one administrator per system. The Information Panel for a particular system includes the name of the system's administrator so other users know whom to contact for help.

See also network administrator and system administrator.

back up

To copy a certain set of files and directories from your hard disk to a tape or other media.

backup tape

A tape that contains a copy of a set of files and directories that are on your hard disk. A full backup tape contains a copy of all files and directories, including IRIX, that are on your hard disk.

baud rate

A term used for the speed (calculated as bits per second) at which the computer sends information to a serial device, such as a modem or terminal.

boot

To start the system by turning on the workstation and monitor; the system is fully booted when you see the console login prompt or the login screen.

button

On a mouse, a button is a switch that you press with a finger. In a window on your screen, a button is a labelled rectangle that you click with a mouse.

CCIR 601

A high-end digital video interface standard developed by the CCIR (Comité Consultatif International de Radiodiffusion, or International Radio Consultative Committee). In CCIR 601 the luminance and chrominance are broken down into three digital signals: one for luminance (brightness) and two for chrominance (color) information. The color information is spatially sub-sampled horizontally so that the two chroma components occupy the same data bandwidth as the luminance component. Both the luminance and chrominance are then multiplexed up to a double rate byte wide data stream. The SGI digital standard used in the O2+ workstation is very similar to 601, with the exception that 601 is balanced ECL, while SGI uses single-ended TTL. Additionally, 601 requires a fixed number of samples per horizontal line, while the SGI implementation is programmable.

CD-ROM disk (CD)

A flat metallic disk that contains information that you can view and copy onto your own hard disk; you cannot change or add to the information on the CD-ROM. CD-ROM is the shortened term for compact disk: read-only memory.

centralized network

A network in which a central server controls services and information; the server is maintained by one or more network administrators. On a centralized network that uses NIS, this server is the NIS master, and all other systems on the network are NIS clients. See also network administrator.

chassis

The external metal framework of the workstation that contains its working parts.

chrominance

In an image reproduction system, a separate signal that contains the color information. Black, white, and all shades of gray have no chrominance and contain only the luminance (brightness) portion of the signal. All colors have both chrominance and luminance. Chrominance is derived from the I and Q signals in the NTSC television system and the U and V signals in the PAL television system. See also luminance.

click

To press and immediately release a mouse button.

composite video

A color-encoding method or a video signal that contains all of the color, brightness, and synchronizing information in one signal. The chief composite television standard signals are NTSC, PAL, and SECAM. See also NTSC and PAL.

configuration file

A system file that you change to customize the way your system behaves. Such files are sometimes referred to as customization files.

confidence test

A test that you run to make sure a particular device (such as the keyboard, mouse, or a drive) is set up and working properly.

connector

Hardware at the end of a cable that lets you fasten the cable to an outlet, port, or another connector.

console window

The window that appears as a stowed icon each time you log in; IRIX reports all status and error messages to this window.

CPU module

The printed circuit board within your workstation chassis that contains the central processing unit (CPU).

current working directory

The directory within the filesystem in which you are currently located when you are working in a shell window.

cursor

The small red arrow on the screen that echoes the movements of the mouse. It changes shape during different activities.

DAT (digital audio tape)

A magnetic tape from which you can read and to which you can copy audio and digital information.

default printer

The printer to which the system directs a print request if you do not specify a printer when you make the request. To set the default printer use the Print Manager.

default subsystems

Portions of a product that are installed automatically if you do not customize a product installation.

defaults

A set of behaviors that SGI specifies on every system. You can later change these specifications, which range from how your screen looks to what type of drive you want to use to install new software.

diagnostics

A series of tests that checks all hardware components of your system.

DIMM (double inline memory module)

A small printed circuit board with several chips that contain additional megabytes of random-access memory (RAM).

DIMM socket

A long, thin, female connector located on the system board into which you insert a DIMM.

directory

A container in the filesystem in which you store other directories and files.

disk resource

Any disk (hard, CD-ROM, floppy, or floptical) that you can access either because it is physically attached to your workstation with a cable, or because it is available over the network using NFS. See also NFS.

disk use

The percentage of space on your disk that contains information.

double-click

To press and release a mouse button twice, very rapidly.

drag

To press and hold down a mouse button, and then move the mouse. This drags the cursor to move icons or to highlight menu items.

drive

A hardware device that lets you access information on various forms of media, such as a hard disk, floppy disk, CD-ROM, and magnetic tape.

drive address

See SCSI address.

external device

Any piece of hardware that is attached to the workstation with a cable.

export

To use NFS software to make all or part of your filesystem available to other users and systems on the network.

female connector

A connector that has indentations or holes into which you plug a male connector. An example of a female connector is an electrical wall outlet that accepts an electrical plug.

field

An area in a window in which you can type text.

file

A container in which you store information such as text, programs, or images that you create using an application.

filesystem

A hierarchy of directories and files. Directories contain other directories and files; files cannot contain directories. The root (/) directory is at the top of the hierarchy.

form

A window that contains buttons that you click and/or fields into which you enter information.

grounded electrical outlet

An electrical wall outlet that accepts a plug with a grounding prong. In the USA, all three-prong outlets are grounded.

handshake

The protocol that controls the flow of information between a workstation and a printer or any other peripheral. A hardware handshake uses only cable wires and pins to control the flow. A software handshake (also called xon-xoff flow control) uses a combination of pins, wires, and software.

highlight

To change the color of an item on the screen by positioning the cursor over the item, pressing and holding the mouse button, and moving the cursor over the item.

home directory

The directory into which IRIX places you each time you log in. It is specified in your login account; you own this directory and, typically, all its contents.

host

Any system connected to the network.

hostname

The name that uniquely identifies each host (system) on the network.

human factors guidelines

A set of standards and suggestions for making your working environment more comfortable and healthy.

icon

A small picture that represents a stowed or closed file, directory, application, or IRIX process.

internal drive

A drive that fits inside the workstation and connects to an internal port; it is never connected with a cable to a visible external port. An internal drive is occasionally referred to as a front-loading drive.

IP address

The Internet Protocol number that uniquely identifies each host (system) on the network. An example of an IP address is 192.0.2.1. It always has four components, separated by periods.

IRIX

SKI's version of the UNIX operating system. See also system software.

ISDN (Integrated Services Digital Network)

A combination of software, hardware, and telephone services that lets you communicate with other systems and networks over a high-speed telephone line, just as you communicate with other systems and networks over an Ethernet cable.

jot

The text editor that comes as a standard utility on Silicon Graphics workstations.

KB (kilobyte)

A standard unit for measuring the information storage capacity of disks and memory (RAM and ROM); 1024 bytes is 1 KB.

LED (light-emitting diode)

A light on a piece of hardware that indicates status or error conditions.

launch

To start an application, often by double-clicking an icon.

local workstation, drive, disk, filesystem, or printer

The physical workstation whose keyboard and mouse you are using, all hardware that is connected to that workstation, and all software that resides on that hardware or its removable media.

log in

To enter your login name so you can start a session on the workstation.

log out

To end a session on the workstation.

login account

A database of information about each user that, at the minimum, consists of login name, user ID, and home directory.

login name

A name that uniquely identifies a user to the system.

login screen

The window that you see after powering on the system, before you can access files and directories. The window can contain one icon for each login account on the system.

luminance

The perceived brightness of a surface. Luminance typically refers to a weighted average of red, green, and blue color values that gives the perceived brightness of the combination. For video systems, luminance is the video signal that describes the amount of light in each pixel. See also chrominance.

MB (megabyte)

A standard unit for measuring the information storage capacity of disks and memory (RAM and ROM); 1024 kilobytes is 1 MB.

male connector

A connector that has raised edges, pins, or other protruding parts that you plug into a female connector. An example of a male connector is an electrical plug that you plug into a wall outlet.

man page

An online document that describes how to use a particular IRIX command.

menu

A list of operations or commands that the workstation can execute.

MIDI (Musical Instrument Digital Interface)

On the O2+ workstation, MIDI devices (such as a keyboard) can be connected to the serial ports.

monitor

A hardware device that displays the images, windows, and text with which you interact to use the system. It is also called a video display terminal (VDT).

monitor video cable

The cable that connects the monitor to the workstation to transmit video signals. It is thick and beige, with large connectors on both ends.

monitor power cable

The cable that connects the monitor to the workstation to provide power to the monitor. It is thick and beige, with a male connector on one end and a female connector on the other.

mount point

The directory on your workstation from which you access information that is stored on a local or remote disk resource.

mount

To make a filesystem that is stored on a local or remote disk resource accessible from a specific directory on your workstation.

mouse

A hardware device you use to communicate with windows and icons. You move the mouse to move the cursor on the screen, and you press its buttons to initiate operations. An optical mouse must always be on the mouse pad for the IRIS system to interpret its movements; a mechanical mouse works on any clean, flat surface.

mouse pad

For an optical mouse, this is the rectangular, metallic surface that “reads” the movements of the mouse. For a mechanical mouse, this is a clean, soft rectangular surface that makes the mouse's track ball roll efficiently.

network

A group of computers and other devices (such as printers) that can all communicate with each other electronically to transfer and share information.

network administrator

The individual(s) responsible for setting up, maintaining, and troubleshooting the network, and for supplying setup information to system administrators of each system.

NFS (Network File System)

A networking software option that lets you access files and directories that reside on the disks of other workstations as if they resided on a local disk in your own workstation.

NTSC

A color television standard or timing format that encodes all of the color, brightness, and synchronizing information in one signal. Used in North America, most of South America, and most of the Far East, this standard is named after the National Television Systems Committee, the standardizing body that created the system in the United States in 1953. NTSC uses a total of 525 horizontal lines per frame, with two fields per frame of 262.5 lines each. Each field refreshes at 60 Hz (actually 59.94 Hz).

open

To double-click an icon, or to select an icon, and then select Open from a menu in order to display a window.

option drive

Any internal drive other than the system disk. Option drives include floppy disk drives, floptical disk drives, secondary hard disk drives, and DAT drives.

outlets

Openings in the hardware to which you attach connectors to make an electrical connection.

PAL

The acronym for Phase Alternation Line or Phase Alternated by Line, by which the workstation attempts to correct some of the color inaccuracies in NTSC. PAL is a color television standard or timing format developed in West Germany and used by most other countries in Europe (including the United Kingdom but excluding France), as well as Australia and parts of the Far East. PAL uses a total of 625 horizontal lines per frame, with two fields per frame of 312.5 lines per field. Each field refreshes at 50 Hz. PAL color encoding is different from NTSC encoding. See also NTSC.

PCI (Peripheral Component Interconnect)

A bus specification. The PCI bus is a high-performance local bus used to connect peripherals to memory and a microprocessor. Many vendors sell devices that plug into the PCI bus.

PROM monitor

The interface that you use to communicate with the system after it is powered on, but before it is booted and running IRIX.

Printer Manager

A tool that you access from the System Manager. You use it to set up printer software and monitor jobs that you send to the printer.

parallel device

Any hardware device that requires a parallel cable connection to communicate with the workstation. A parallel interface transfers bits of information via a number of wires simultaneously.

parallel port

An outlet on the workstation to which you connect external parallel devices. A parallel interface transfers bits of information via a number of wires simultaneously.

password

A combination of letters and/or numbers that only you know; it is an optional element of your login account. If you specify a password for your account, you must type it after you type your login name before the system lets you access files and directories.

pathname

A name that specifies the location of a file or directory within a hierarchied filesystem. It begins with the name of the root (/) directory and ends with the name of the subordinate directory or files to be located. See also filesystem.

peripheral

A hardware device, such as a tape device, that adds more functionality to the basic workstation. See also external device and internal drive.

port

An outlet on the workstation to which you attach cable connectors.

power-on diagnostics

A series of tests that automatically checks hardware components of your system each time you turn it on.

power cable

The cable that connects the workstation to a grounded electrical outlet.

power off

To turn off the power switches on the workstation chassis and the monitor.

power supply

The hardware within the chassis that directs power from an electrical outlet to the chassis, the monitor, and internal SCSI devices. It also contains the power switch, reset button, and fan.

power on

To turn on the power switches on the workstation chassis and the monitor.

prompt

A character or word that the system displays in an IRIX shell. It indicates that the system is ready to accept commands. The default prompt for regular user accounts is %; the default prompt for the root account is #.

quit

To stop running an application.

remote workstation, drive, disk, filesystem, or printer

A hardware device or the information or media it contains that you can access across the network; it is not physically connected to your workstation.

reset button

A physical button on the workstation that you press to turn off and then immediately restore power to the workstation. You should never press this button while IRIX is running, unless all attempts to shut down the system using software fail. See also shut down.

restore (files)

To copy files that once resided on your hard disk from another disk or tape back onto your hard disk.

root account

The standard IRIX login account reserved for use by the system administrator. This account's home directory is the root (/) directory of the filesystem; the user of the root account has full access to the entire filesystem (that is, this user can change and delete any file or directory). The user of this account is sometimes referred to as the super-user. See also administrator and system administrator.

root (/) directory

The directory at the top of the filesystem hierarchy. See also filesystem.

SCSI (Small Computer System Interface)

SCSI (pronounced “scuzzy”) is a high-speed input/output specification for small computers.

SCSI address

A number from one to seven that uniquely identifies a SCSI device to a system. No two SCSI devices that are physically connected to the same workstation can have the same SCSI address. See also SCSI.

SCSI address dial

A small plastic dial, supplied by SGI, that is connected to most external SCSI devices. You click its small buttons to select a SCSI address for a new SCSI device. See also SCSI.

SCSI bus line

The combined length of all internal and external SCSI cables in a system. See also SCSI.

SCSI cable

A cable that connects a SCSI device to a SCSI port on a workstation. See also SCSI.

SCSI device

A hardware device that uses the SCSI protocol to communicate with the system. Hard disks, floppy disks, floptical disks, CD-ROMs, and tape drives are all SCSI devices. See also SCSI.

SCSI terminator

A metal cap that you plug into any open SCSI port on a SCSI bus line. No SCSI devices on a SCSI bus line will work unless all SCSI ports are occupied by either cables or terminators. See also SCSI.

screen

The portion of the monitor that displays information.

select

To position the cursor over an item, and then click the mouse button.

serial device

Any hardware device that requires a serial cable connection to communicate with the workstation.

serial port

An outlet on the workstation to which you connect external serial devices.

server

A system that other systems on network access to use its disk space, software, or services.

shell

A window into which you type IRIX commands.

shielded cable

A cable with a protective covering that reduces the possibility of interference with radio, television, and other devices.

shut down

To safely close all files, log out, and bring the workstation to a state in which you can safely power it off. From the Toolchest, select System > Shutdown.

software option

Any software product that you buy from SGI other than the standard system software that comes on your system disk.

standalone workstation

A workstation that is not connected to a network.

static electricity

Whenever your body is in physical contact with metal parts (including printed circuit boards) of computer equipment, there is the potential for you to feel an electrical shock (electro-static discharge or ESD) that could damage the equipment. To prevent this, you must always wear a wrist strap when working with internal parts of a workstation.

subsystem

A portion of a software product. Each product consists of several subsystems; some are required and some are optional.

super-user

An alternate name for the user of the root login account. See also administrator, root account, and system administrator.

S-video

An increasingly popular analog video signal format that achieves higher picture quality than composite video by passing the luminance (brightness) and chrominance (color) information on separate wires.

system

All the hardware and software that make up the workstation.

system administrator

The individual(s) responsible for setting up, maintaining, and troubleshooting a networked or standalone system.See also administrator and network administrator.

system crash

This occurs when the IRIX operating system fails and the system will not accept any keyboard or mouse input.

system disk

The physical disk that contains the standard IRIX operating system software.

System Manager

A set of tools that the administrator uses to set up and manage the workstation. To access the System Manager, from the Toolchest, you select System.

system software

The standard IRIX operating system software and SGI tools on the system disk and on the tape or CD-ROM that you use in the event of a system crash.

TCP/IP (Transmission Control Protocol/Internet Protocol)

A set of networking protocols for wide area networks (WANs) that is also gaining popularity on local area networks (LANs).

thumbscrew

The ridged knob attached to a screw in a cable connector. You turn the thumbscrew to secure the connector to an outlet.

Toolchest

The menus in the upper left-hand corner of the desktop. From the Toolchest, you can select system tools such as the System Manager and Software Manager.

upgrade (hardware)

Hardware that you add to the basic workstation that increases performance, such as additional memory and option boards.

unmount

To cause a filesystem that is accessible from a specific directory on your workstation to be temporarily inaccessible.

user ID

A number that uniquely identifies a user to the system.

window

A portion of the screen with text or graphics that you can manipulate.

workstation

The physical hardware that contains the CPU, graphics boards, a system disk, and a power supply. You connect it to a monitor, keyboard, and mouse to configure a working system. It is also sometimes referred to as the chassis.

wrist strap

A band with a loop for your wrist at one end and copper foil at the other. You attach the end with the foil to a metal part of the workstation and place the loop around your wrist. You use the strap whenever you work with internal components of the workstation to avoid electrical shocks to yourself and the components. See also static electricity.