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Computer Terminologies
(Courtesy of Cisco Networking Academy)
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ACPI - Advanced Configuration and Power Interface enables the operating system to control the amount of power given to each device attached to the computer.
Address Bus - A unidirectional pathway that carries addresses generated by the CPU to the memory and I/O elements of the computer. See also: I/O, Bus, Data Bus, and Internal Bus.
AGP - Accelerated Graphics Port. Dedicated high-speed bus that is used to support the high demands of graphical software. This slot is reserved for video adapters only. See also: Bus, PCI, and Expansion Slot.
Algorithm - A systematic procedure that performs a specific task. Computers use algorithms to speed up and simplify procedures.
ALU - Arithmetic/Logic Unit. The component of the CPU that performs both the arithmetic and the logical operations for the computer. See also: CPU and Control Unit.
Analog - A type of device that represents data by continuously variable physical quantities, such as length, mass, temperature, or pressure.
Analog Modem
A modulator-demodulator that converts the computer's digital pulses to tones that are carried over analog telephone lines. See also: modem.
AP - 1. Application process. 2. Application processor.
Application - A program that performs a function directly for a user.
ASCII - American Standard Code for Information Interchange. A code for representing English characters as numbers, with each letter assigned a number from 0 to 127, making it possible to transfer data from one computer to another.
Asynchronous - In terms of data transmission, asynchronous means that no clock or timing source is needed to keep both the sender and the receiver synchronized.
AT - Advanced Technology. An IBM PC model with an Intel 80286 processor. This term is used to describe the form factor of one type of computer motherboard, power supply, and case.
ATM - Asynchronous Transfer Mode. A network technology based on transferring data in cells or packets of a fixed size. The small, constant cell size allows ATM equipment to transmit video, audio, and other data over the same network assuring that no single type of data hogs the line. See also: Network.
AVI - Audio Video Interleave. The standard audio/video format for Microsoft Windows. AVI files, which end with an .avi extension, require a special player.
Baud - The number of signaling elements that occurs each second, named after the inventor of the Baudot telegraph code, J.M.E. Baudot.
BBS - Bulletin Board System. An electronic message center that serves specific interest groups.
Binary - A number system using two unique digits. Because of a computer’s electrical nature, all operations are performed using a representation of an open or closed circuit (0 for off, and 1 for on); therefore, computers use the binary system when calculating operations. See also: Decimal, Hexadecimal, and Numbering System.
Bios - Basic Input / Output System. The program stored in a ROM chip in the computer that provides the computer with basic code to control the computer’s hardware and perform diagnostics on it. The BIOS prepares the computer to load the operating system. See also: Chip, ROM, and CMOS.
Bit - Binary Digit. The smallest unit of information in a computer. A bit can take the value of either one or zero, and it is the binary format in which data is processed by computers. See also: Byte.
Bitmap-Based - A type of printer font that is represented as a graphics image with rows and columns of dots. This type of font is also known as raster-based. See also: Font.
Boolean - A form of algebra where all values are reduced to TRUE or FALSE. Boolean logic is used with computers due to its similarities with the binary numbering system. See also: Binary and Numbering System.
Boot - To start a computer. This is a reference to pulling on the bootstraps on the top of your boots to help get your boots on being compared to taking the first step in a process. See also: Cold Boot and Warm Boot.
Boot Disk - A disk that can be used to start up a computer. The boot disk contains the files needed for an operating system to run. See also: Boot.
Bootstrap Program - A small program located in the BIOS chip that tests the computer’s hardware then locates and loads the operating system into RAM. See also: BIOS, Chip, RAM and Boot.
Broadcast Domain - Set of all devices that receive broadcast frames originating from any device within the set. Broadcast domains typically are bounded by routers because routers do not forward broadcast frames.
Bus - The media through which data is transferred from one part of a computer to another. The bus can be compared to a highway on which data travels within a computer. See also: Address Bus, Control Bus, Data Bus, Expansion Bus, and Internal Bus.
Byte - A byte is a unit of measure used to describe an amount of data. One byte consists of eight bits of data. See also: Megabyte, Gigabyte, Bit, and File.
Cable Modem - Modulator-demodulator device that is placed at a subscriber location to convey data communications on a cable television system.
Cache - The storage of instructions or data for future use. See also: RAM.
CAD - Computer Aided Design. The use of computers to design products. CAD systems are high-speed workstations or desktop computers with specialized CAD software.
Category 1 Cable - A type of power limited UTP cable used for alarm systems and basic communications. See also: UTP.
Category 2 Cable - A low performance UTP cable used for voice and other low speed data applications. See also: UTP.
Category 3 Cable - A type of UTP cable used for hardware with transmission characteristics up to 16 MHz. Typical applications include 10BASE-T Ethernet, 4-Mbps Token Ring, and basic rate ISDN. See also: UTP, Ethernet, Mbps, Token Ring, and ISDN.
Category 4 Cable - A little used UTP cable used for applications including 16 Mbps Token Ring. See also: UTP and Token Ring.
Category 5 Cable - A type of UTP cable used for most new data installations. It supports hardware with transmission characteristics up to 100 MHz. Typical applications include 16 Mbps Token Ring and Ethernet, among others. See also: UTP, Token Ring, and Ethernet.
Category 5e Cable - A Category 5 type UTP cable used for higher transmission bandwidth for the frequencies beyond 100MHz.
CB - Citizens Band. A radio-frequency band used specifically for private radio communications.
CDDI - Copper Distributed Data Interface. The implementation of FDDI protocols over STP and UTP cabling.
CD-ROM - Compact Disk Read Only Memory. A type of optical disk capable of storing up to one gigabyte of data. See also: Byte, Megabyte, and Gigabyte.
Channel - A pathway or route through which information is transmitted. See also: Bus.
Chip - A very small slice of silicon or germanium processed to have electrical characteristics so that it can be developed into an electronic component. See also: CPU and Semiconductor.
Circuit Board - A thin plate on which chips and other electronic components are attached.
CLI - Command-line interface. An interface that allows the user to interact with the operating system by entering commands and optional arguments. The UNIX operating system and DOS provide CLIs.
Client - An application that runs on a computer relying on a server to perform certain operations. See also: Server, Client Operating System, and Client/Server.
Client Operating System - Also referred to as a desktop operating system, it is the operating system software that runs on the network's workstations that can access resources on the network. See also: Operating System, Resources, and Network.
Client/Server - The relationship between computers on a network where the “client” computer uses the resources on a “server” computer. See also: Client, Server, and Resources.
CMOS - Complementary Metal Oxide Semiconductor. A type of semiconductor that requires very little power. Personal computers use this device to store the date, time, and system configuration data. See also: Semiconductor, ROM, and Chip.
CMTS - Cable Modem Termination System. A component that exchanges digital signals with cable modems on a cable network. A cable modem termination system is located at the local office of a cable television company.
Coax - Coaxial cable is copper-cored cable surrounded by a heavy shielding that is used to connect computers in a network. Either thin or thick coax can be used.
Cold Boot - Powering a computer up from the off position. See also: Boot and Warm Boot.
Collision Domain - In Ethernet, the network area within which frames that have collided are propagated. Repeaters and hubs propagate collisions; LAN switches, bridges, and routers do not.
COM - Common equipment. Items used by more than one channel or equipment function.
Commercial Backbone - An internet work of commercially operated networks that are provided by telecommunications companies. Internet service providers (ISPs) connect to these commercial networks to provide connections to the Internet. See also: Backbone, ISP, and Internet.
Computer - An electrical machine that can execute a list of instructions and perform calculations based on these instructions.
Configuration - The components that make up a computer system when referring to hardware, or the defined parameters of a device when referring to software. See also: Hardware and Software.
Connectivity Devices - Devices that are used to connect cable segments, connect two or more smaller networks into a larger network, or divide a large network into smaller ones.
Control Bus - This bus carries the control and timing signals needed to coordinate the activities of the entire computer. Control bus signals, are not necessarily related to each other. Some are output signals from the CPU, and others are input signals to the CPU from I/O elements of the system. See also: Bus, Address Bus, Data Bus, and Internal Bus.
Controller - A chip or device that controls data transfer between the computer and the devices that are attached to it. See also: Chip.
Control Unit - The component of the CPU that instructs the rest of the computer system on how to follow a program’s instructions. It directs the movement of data to and from processor memory, holds data and instructions in the ALU, and directs control signals between the CPU and external devices. See also: CPU, and ALU.
Coprocessor - A processing unit that assists the CPU with certain types of operations in order to free the CPU of common tasks that can slow it down. See also: CPU.
Corona Wire - A wire in a laser printer or photocopier that is subjected to high voltage which is transferred to the drum and paper in the form of static electricity to charge the surface with positive ions.
CPU - Central Processing Unit. The chip or PCB where most of the calculations in the computer take place. See also: Control Unit, ALU, Chip, and PCB.
Cross Talk - Interfering energy transferred from one circuit to another.
CRT - Cathode Ray Tube. An electronic device that fires an electron beam across a phosphorous coated tube to illuminate parts of the screen. When many passes are made across the screen, the screen produces an image. CRTs are used in television sets and computer monitors.
CSMA/CD - Carrier Sense Multiple Access Collision Detect. Media-access mechanism wherein devices ready to transmit data first check the channel for a carrier. If no carrier is sensed for a specific period of time, a device can transmit. If two deices transmit at once, a collision occurs and is detected by all colliding devices. This collision subsequently delays retransmissions from those devices for some random length of time. Ethernet and IEEE 802.3 use CSMA/CD access.
Daemon - A program that runs in the background and performs specific functions at certain times or in response to events.
DARPA - Defense Advanced Research Projects Agency. The central research and development organization for the Department of Defense.
Database - A collection of data that is organized so that its contents can be easily accessed, managed, and updated.
Data Bus - A bidirectional pathway for data flow. Data can flow along this bus from the CPU to memory during a write operation, and data can move from the computer memory to the CPU during a read operation. See also: Bus, Address Bus, Control Bus, and Internal Bus.
DDR SDRAM - Double Data Rate SDRAM. A type of memory that doubles in bandwidth by transferring data twice per cycle (on both the rising and falling edges of the clock signal). See also: SDRAM, DRAM, and RAM.
Decimal - A number system based on the number “10”. This number system is used on an everyday basis. See also: Numbering System and Hexadecimal.
Default - A value or setting that is automatically applied by a device or program.
Desktop - The metaphor used to portray file systems. A desktop consists of pictures, called icons, which show files, folders, and any resource available to a user in a GUI operating system. See also: GUI, Operating System, and Icon.
Desktop Computer - A type of computer designed to fit on top of a desk, usually with the monitor on top of the computer to conserve space.
DHCP - Dynamic Host Configuration Protocol. Provides a mechanism for allocating IP addresses dynamically so that addresses can be reused when hosts no longer need them.
Diagnostic - Serving to identify the cause of a problem as in diagnostic software that will find out what problem a computer may be having.
Digital - A system that is based on events or data that is not continuous such as the binary system. See also: Binary and Analog.
Digitize - To convert data to digital form. See also: Digital.
Dimm - Dual Inline Memory Module. A circuit board with a 64-bit data bus that holds memory chips. See also: Circuit Board, RAM, and SIMM.
Din - Deutsche Industrinorm. The standards-setting organization for Germany.
Dip Switch - A small switch on a circuit board used for configuring the board for a specific application. See also Circuit Board and Configuration.
Directory - A type of file that organizes other files in a hierarchical structure. See also: File.
DMA - Direct Memory Access. A method for transferring data from the computer’s main memory directly to the device that needs it without it having to pass to and from the CPU. This makes the transfer faster. See also: I/O Address and IRQ.
DNS - Domain Name System. An Internet service that converts names to IP addresses. See also: IP Address and TCP/IP.
DoD Four-Layer Model - The Department of Defense’s DARPA Internetwork Project model that eventually grew into the Internet. See also: DARPA.
Domain - A logical group of computers and electronic devices with a common set of rules and procedures administered as a unit.
DOS - Disk Operating System. A 16-bit command-line interface operating system that does not support multiple users or multitasking. See also: Operating System.
Dot Matrix - A type of printer that produces characters and illustrations by striking pins against an ink ribbon and print media to print closely spaced dots in a certain configuration, much like a typewriter.
Download - To copy data from a main source to a peripheral device, such as the transfer of a file from an ISP or BBS to a local computer. See also: Peripheral, File, ISP, and BBS.
Downstream - Set of frequencies used to send data from the headend to a subscriber.
DPI - Dots Per Inch. A measurement which indicates the resolution of an image. The more dots per inch, the higher or better the resolution of the image will be.
DRAM - Dynamic Random Access Memory. A type of RAM that only holds its data if it is continuously accessed by special logic called a refresh circuit. See also: RAM.
DRDRAM - irect Rambus DRAM. Memory that works more like an internal bus than a conventional memory subsystem. DRDRAM is based around the Direct Rambus Channel, a high-speed 16-bit bus running at a clock rate of 400 MHz, where transfers are accomplished on the rising and falling edges of the clock to run at much higher speeds than would be possible if the bus were wide. See also: RAM and DRAM.
DSL - Digital Subscriber Line. A sophisticated modulation method for transmitting data over copper wires. See also: Digital Dumb Terminal
Low cost devices that usually consist of a monitor, keyboard, and a communication port to talk to a mainframe computer. Initially these terminals were hard wired directly to communication ports on the mainframe and the communications were asynchronous. See also: Mainframe.
DVD-ROM - Digital Versatile Disk Read Only Memory. An optical storage media capable of holding from 4.7 GBs to 17GBs with faster access and transfer rates than CD-ROMs. See also: CD-ROM and Gigabyte.
EEPROM - Electrically Erasable Programmable Read Only Memory. A special type of PROM that can be erased by exposure to an electrical charge. See also: PROM, RAM, EPROM, and CMOS
EIDE - Enhanced Integrated Drive Electronics. A mass storage standard that supports data transfer rates between 4 and 16.6 MBps and devices up to 8.4 GB in size. See also: IDE, MB, and GB.
EMI - Electromagnetic Interference. Interference by electromagnetic signals that can cause reduced data integrity and increased error rates on transmission channels.
E-mail - Electronic mail
Emoticons - Emotion Icons. Text-based icons representing smiles, frowns and other body language indicators. See also: Icon.
Encryption - The translation of data into a code that needs to be decrypted in order for it to be legible.
EPROM - rasable Programmable Read Only Memory. A special type of memory that can be erased by exposure to ultraviolet light. See also: ROM, PROM, EEPROM, and CMOS.
ESD - Electrostatic Discharge) The discharge of static electricity from one conductor to another conductor of a different potential.
Ethernet - A LAN protocol developed in 1976 by Xerox Corporation in cooperation with DEC and Intel. Ethernet uses a bus or star topology and supports data transfer rates of 10 Mbps. See also: LAN, Network, Topology, and Mbps.
Expansion Board - A PCB inserted into a computer’s expansion slot to increase the capabilities of the computer. See also: PCB, PCI, Expansion Slot, and Expansion Bus.
Expansion Bus - This bus enables expansion boards to access the CPU and memory. See also: Expansion Board, PCI, CPU, Bus, and Control Bus
Expansion Slots - An opening on a computer where a PCB or PC Card can be inserted to add capabilities to the computer. See also: ISA, PCI, BUS, Expansion Bus, Expansion Board, PCMCIA, and PCB.
FDD - See also: Floppy Disk Drive.
FDDI - Fiber Distributed Data Interface. A set of protocols that allows the transmission of data over fiber optic cable. See also: Fiber Optics and Protocol.
FDM - Frequency-division Multiplexing. Technique whereby information from multiple channels can be allocated bandwidth on a single wire based on frequency.
Fiber Optics - Cabling that has a core made of strands of glass or plastic, through which light pulses are carried. Fiber has many advantages over copper in terms of transmission rate and signal integrity over distance; however, it is more expensive and more difficult to work with. See also: FDDI and Cable.
File - A collection of similar information given a name for easy storage and retrieval. See also: File Management System.
File Management System - A collection of similar information given a name for easy storage and retrieval. See also: File Management System.
File Transfer Protocol (FTP) - The protocol used by the Internet community to send files. See also: Protocol and Internet.
Firmware - Data that has been stored on ROM chips. See also: Chip, ROM, PROM, EPROM, EEPROM, and CMOS.
Flash ROM - A special type of memory that can be reprogrammed in blocks of data instead of one byte at a time. See also: ROM, PROM, EPROM, EEPROM, and CMOS.
Floppy Disk - A portable, removable magnetic disk used to store data using a floppy disk drive. See also: Floppy Disk Drive
Floppy Disk Drive - A device that spins a magnetic floppy disk to read and write data on it. See also: Floppy disk
Folder - An object in a graphical user interface capable of storing multiple files and other folders. See also: File and GUI.
Font - The combination of typeface and other qualities, such as size, pitch, and spacing that comprise a set of characters.
FPM RAM - Fast Page Mode RAM. This type of memory gives faster access to data that resides on the same page. See also: RAM.
Freeware - Software that is given away freely by the author for private use. The copyright is retained by the author of the software. See also: Software and Shareware.
FTP - See also: File Transfer Protocol.
Fuser - A roller within a laser printer or photocopier that uses high heat to melt toner particles to paper. See also: Toner.
GDI - Graphical Device Interface. Windows standard for transmitting graphical objects directly to output devices, such as monitors and printers to increase the speed of the output.
Gigabyte (GB) - One thousand Megabytes. See also: Megabyte and Byte.
Gigaheertz (Ghz) - One billion (1,000,000,000) cycles per second. This is a common measurement of the speed of a processing chip.
Ground - An electrical connection with a common return for a circuit with an arbitrary zero of potential
GUI - Graphical User Interface. Software that uses a computer’s graphics ability to organize and display resources and objects making it easier to use and eliminating the need for a command-line interface. See also: Software and Resources.
Hardware - The physical electronic components that make up a computer system.
Heat Sink - A device that dissipates heat from electronic components into the surrounding air.
Hexademical - The base-16 number system. This system can represent a byte as two consecutive hexadecimal digits. See also: Decimal and Numbering System.
HDD - See also: Hard Disk Drive.
Hertz - A unit of frequency. It is the rate of change in the state or cycle in a sound wave, alternating current, or other cyclical waveform. See also: Microprocessor.
Host - A computer system that is accessed by a user at a remote location.
HTML - See also: HyperText Markup Language.
HTTP - See also: HyperText Transfer Protocol.
Hybrid Network - A network in which the software products of different vendors interoperate, especially concerning the server operating systems. See also: Network, Server, and Operating System.
Hyperlink - An item in an electronic document that links to another object such as a position in a document or a different document.
Hyptertex Markup Language (HTML) - This is the language used to write World Wide Web documents. See also: World Wide Web and HyperText Transfer Protocol.
Hypertex Transfer Protocol (HTTP) - The protocol of the World Wide Web. This protocol provides standards by which messages are formatted and sent. See also: World Wide Web, HyperText Markup Language, and Protocol.
HZ - See also: Hertz.
ICMP - Internet Control Message Protocol. Network layer Internet protocol that reports errors and provides other information relevant to IP packet processing. Documented in RFC 792.
IDE - Integrated Drive Electronics
IETF - Internet Engineering Task Force. The primary standards organization for the Internet made up of developers, network operators and developers, and anyone who is interested in the evolution of the Internet. See also: Internet and Network.
IMAP - Internet Message Access Protocol. A protocol for retrieving e-mail that supports more advanced features than POP3. See also: Protocol, E-Mail, and POP.
IMTC - International Multimedia Teleconferencing Consortium. A non-profit corporation comprising more than 150 companies with the intention of promoting the development and use of interoperable multimedia teleconferencing with international standards.
Infrared - A type of light wave capable of transmitting data from one device to another without using cables.
Internal Bus - The bus that connects all the internal computer components to the CPU and main memory. See also: Bus, Address Bus, Data Bus, and Control Bus.
Internet - The decentralized global network that connects millions of computers worldwide. See also: Network.
Internet Backbone - A group of pathways used by local networks to connect over long distances. The Internet backbones are made up of connection points called nodes. See also: Network, Backbone, and Commercial Backbone.
I/O - Input / Output. Any operation, program, or device that transfers data to or from a computer. Typical I/O devices are printers, hard disks, keyboards, and mice.
I/O Address - Resources used by virtually every device in the computer that represent locations in memory that are designated for use by various devices to exchange information between themselves and the rest of the PC. See also: I/O, Peripheral, and Resources.
IP - A protocol that allows a package to be addressed and dropped in the system. There is no direct link between the sender and the recipient. See also: Protocol and TCP/IP.
IP Address - A numerical identifier for an electronic device on a network utilizing the TCP/IP protocol in the form of a 32-bit numeric address written as four numbers separated by periods. See also: TCP/IP, Binary, Numbering System, and Protocol.
IRC - Internet Relay Chat. A chat system that allows people from around the world to participate in live chat sessions
IRQ - Interrupt Request Line. The hardware devices used to send interrupt signals to the CPU in a computer. See also: DMA and I/O Address.
ISA - Industry Standard Architecture. A 16-bit expansion slot that transfers data with the motherboard at 8 MHz. See also: Expansion Slot and Hertz.
ISDN - Integrated Services Digital Network. A standard for sending data, voice, and video over telephone lines supporting a data transfer rate of 64 Kbps. ISDN service normally provides two lines called B channels, where one line is used for data and one for voice. It is possible to use both lines for data, achieving transfer rates up to 128 Kbps
ISO - International Organization for Standardization. International organization that is responsible for a wide range of standards, including those relevant to networking. ISO developed the OSI reference model, a popular networking reference model
ISP - Internet Service Provider. A company that provides users with a connection to the Internet. See also: Internet.
IT - Information Technology. The subject concerned with all aspects of managing and processing information
ITU - International Telecommunications Union. Intergovernmental organization through which public and private organizations develop telecommunications. The ITU is responsible for adopting international treaties, regulations, and standards governing telecommunications. See also: Telecommunications
Kernal - The main module of the operating system that provides all the essential services needed by applications. See also: Operating System.
Keyboard - The device used to enter data into a computer using typewriter-like keys.
Kilobit (Kb) - Approximately 1000 bits (precisely 1024 bits). See also: Bit and Byte.
Kilobits per second (Kbps) - This is a standard measurement of the amount of data transferred over a network connection. Kbps is a data transfer rate of approximately 1,000 bits per second.
Kilobyte (KB) - Approximately 1000 bytes (precisely 1024 bytes). See also: Bit and Byte.
Kilobytes per second (KBps) - Is a standard for the measurement of the amount of data transferred over a network connection. KBps is a data transfer rate of approximately 1,000 bytes per second.
Laptop Computer - A self-contained portable computer small enough to use on a person’s lap.
Laser - Light Amplification by Stimulated Emission of Radiation. A device that generates electromagnetic radiation in the form of visible, infrared, or ultraviolet light
LED - Light Emitting Diode. A semiconductor device that emits visible light when an electric current passes through it. See also: Semiconductor.
Logical Topology - The path that signals take from one computer to another which can correspond to the physical topology. See also: Physical Topology and Topology.
LPT - Line Printer Terminal. The designation of any printer as seen by an operating system. See also: Operating System.
MAE - Metropolitan Area Exchanges. A network access point where Internet service providers connect to each other. See also: Network, AP, Internet, and ISP.
Mainframe - A large and expensive computer capable of supporting hundreds, or even thousands, of users simultaneously.
MAN - Metropolitan-Area Network. A network that is between the LAN and the WAN in size. This is a network that covers roughly the area of a large city or metropolitan area. See also: Network, LAN, and WAN
Material Safety Data Sheet - Data sheets on hazardous materials indicating hazards and their handling.
Mb - Megabit.
MB - Megabyte.
Media - The various physical environments through which transmission signals pass. See also: Fiber Optic, Coax and Cable.
Megabit (Mb) - Approximately 1 million (actually 1,048,576) bits. See also: Bit and Byte.
Megabit per second (Mbps) - This is a standard for the measurement of the amount of data transferred over a network connection. Mbps is a data transfer rate of approximately 1,000,000 (106) bits per second.
Megabyte (MB) - Approximately 1 million (actually 1,048,576) bytes. A megabyte is sometimes referred to as a "meg". See also: Bit and Byte.
Megabyte per second (MBps) - This is a standard for the measurement of the amount of data transferred over a network connection. MBps is a data transfer rate of approximately 1,000,000 (106) bytes per second.
Megahertz (Mhz) - One million cycles per second. This is a common measurement of the speed of a processing chip.
Microprocessor - A chip that contains a CPU. See also: Chip and CPU.
Minicomputer - A multiprocessing system capable of providing resources to between 4 and 200 users simultaneously. See also: Microprocessor and Resources.
Modem - Modulator-demodulator. Device that converts digital and analog signals. At the source, a modem converts digital signals to a form suitable for transmission over analog communication facilities. At the destination, the analog signals are returned to their digital form. Modems allow data to be transmitted over voice-grade telephone lines.
Motherboard - The main circuit board in a computer. This board connects all of the hardware in the computer together. See also: Circuit Board and Hardware.
Mouse - A device used to control the movement of a pointer in a GUI. See also: GUI.
MSAU - Multistation Access Unit. Wiring Concentrator to which all end stations in a Token Ring network connect. The MSAU provides an interface between these devices and the Token Ring interface of a router. Sometimes abbreviated as MAU.
MSDS - See also: Material Safety Data Sheets.
Multi-point - Software in which more than two participants can communicate simultaneously. See also: Software.
Multiprocessing - Allows a computer to have two or more CPUs that programs share. See also: CPU.
Multitasking - A computer’s capability to run multiple applications at the same time.
Multithreading - The capability for a program to be broken into smaller parts that can be loaded as needed by the operating system. Multithreading allows individual programs to be multitasked. See also: Operating System and Multitasking.
Multi-user - Two or more users running programs and sharing peripheral devices, such as a printer, at the same time. See also: Peripheral and Program.
Name Resolution - Generally, the process of associating a name with a network location.
NAUN - Network Active Upstream Neighbor. In Token Ring or IEEE 802.5 networks, the closest upstream network device from any given device that is still active.
Network - Two or more computer systems connected together in order to share resources. See also: Resources.
Nibble - A nibble is half a byte or four bits.
NIC - Network Interface Card. This card typically goes into a PCI or PCMCIA (PC card) slot in a computer and connects to the network medium, which in turn is connected to other computers on the network. See also: Expansion Slot, PCI, and PCMCIA.
NNTP - Network News Protocol. The protocol used to post, distribute, and retrieve USENET messages. See also: Protocol and USENET.
Node - Endpoint of a network connection or a junction common to two or more lines in a network. Nodes can be processors, controllers, or workstations. Nodes, which vary in routing and other functional capabilities, can be interconnected by links, and serve as control points in the network. Node sometimes is used generically to refer to any entity that can access a network, and frequently is used interchangeably with device. See also Host.
NOS - Network Operating System. The operating system software used on a server. The term sometimes refers to the networking components of a client operating system. See also: Operating System, Network, Client/Server, Client Operating System, Server, and Client.
NSF - National Science Foundation. An independent U.S. government agency responsible for promoting science and engineering through research and education projects in science and engineering.
NTSF - New Technology File System. A type of file system that provides improved fault tolerance over traditional file systems, and also provides file-level security. See also: File and File Management System.
Number Systems - Sets of values used to represent quantity. See also: Binary, Decimal, and Hexadecimal.
Operating System - The program that performs all of the system tasks and provides an environment in which other programs can be run. See also: Program and NOS.
OSI - Open System Interconnection) model – an ISO standard that defines a networking structure for implementing protocols in seven layers to transfer data. See also: ISO, Network, and Protocol.
Packet Switching - Refers to protocols where messages are divided into packets before they are sent, then transmitted individually to a destination to be recompiled into the original message. See also: Protocol and Packet.
Parallel - A type of bus that transfers multiple streams of data simultaneously. See also: Bus.
Partition - To divide memory or mass storage into isolated sections. Once a disk is partitioned, each partition will behave like a separate disk drive. See also: Hard Disk Drive.
PC - Personal Computer
PCB - Printed Circuit Board. See also: Circuit Board.
PCI - Peripheral Component Interconnect. A 32-bit local bus slot that allows the Bus direct access to the CPU for devices such as memory and expansion boards and allows the CPU to automatically configure the device using information contained on the device. See also: Bus, Internal Bus, Expansion board, Expansion Bus, and CPU.
PCL - Printer Control Language. A PDL developed by Hewlett Packard. See also: PDL.
PCMCIA - Personal Computer Memory Card International Association. An organization that has developed the standards for small, credit card-sized devices called PC Cards. PC Cards are designed to add memory and peripheral devices to portable computers. See also: Peripheral and Laptop.
PDA - Personal Digital Assistant. A handheld multifunction electronic device capable of combining cellular phone service, fax, and personal organizer abilities together. Most PDAs use a stylus to enter data necessitating the use of handwriting recognition technology.
PDL - Page Description Language. A language that is used to describe the layout and contents of a printed page when controlling laser printers.
Peripheral - Any device in a computer system that is not essential to the operation of the computer.
Photosensitive - Responsive to light or other radiant energy.
Physical Topology - The layout or physical shape of the network. Refers to the way the computers are arranged so that cabling goes from one to another in a certain physical shape. See also: Logical Topology and Topology.
Pixel - Picture Element. The smallest part of a graphic image. Many pixels close together make up the image on the computer monitor.
Plenum - The plenum is the space between a false ceiling and the floor above, through which cabling can be run. See also: Cable.
PnP - Plug and Play. The ability of a computer to automatically configure the devices that connect to it. See also: PCI.
Point-to-Point - A one-to-one connection.
POP - Post Office Protocol. A protocol used by e-mail clients on a network to retrieve e-mail from the mail server. See also: Protocol, E-Mail, Client, Server, and Network.
Port - An interface on the computer where a device is connected. See also: Peripheral, USB, Serial, and Parallel.
POST - Power-On Self Test. Diagnostic tests run by the computer when it is turned on to test hardware. See also: Hardware.
POTS - Plain Old Telephone Service
Postscript - A PDL developed by Adobe Systems. See also: PDL.
Power Supply - A PDL developed by Adobe Systems. See also: PDL.
PPM - Pages Per Minute
PPP - Protocol. A protocol for connecting a computer to the Internet that provides error checking features. See also: Protocol, Internet, SLIP, and TCP/IP.
Printer Driver - A program that feeds data to a printer with the correct control commands for that certain printer.
Printer Memory - A specialized type of memory that can be installed in a printer that will increase its capabilities.
Print Head - The assembly in a dot-matrix or inkjet printer that moves across the paper to create the text or image.
Print Server - A computer that manages one or more printers for computers on a network. See also: Network and Server.
Processor - See also: Microprocessor and CPU.
Program - An organized list of instructions that, when executed, causes the computer to behave in a predetermined manner.
Programmer - A person who writes computer programs. See also: program.
PROM - Programmable ROM. a type of ROM that can be programmed using special equipment and can be written to only once. See also: ROM, EPROM, EEPROM, and CMOS.
Protocol - A set of rules by which computers communicate. A protocol is much like the syntax of a language rather than the language itself.
PSN - Packet-Switched data Network. A network that uses packet-switching technology for data transfer. Sometimes called a PSDN. See also: packet switching.
Push Technologies - Sending electronic information without the request of the receiver.
PVC - Polyvinyl Chloride. The material out of which the jacket on non-plenum-grade cable is made. It cannot be used for plenum-grade materials. PVC does not meet the safety codes for installation in the ceiling because it gives off a poisonous gas when burned. See also: Cable and Plenum.
Query - Message used to inquire about the value of some variable or set of variables.
Queue - To line up tasks for a computer or device such as a printer.
RAMDAC - Random Access Memory Digital to Analog Converter. A specialized form of memory designed to convert digitally encoded images into analog signals for display. It is made of an SRAM component (for storing the color map) and three DACs, one for each electron gun. See also: DAC, SRAM, Digital, and Analog.
RAS - See also: Remote Access Server and Remote Access Services.
RDDRAM - See also: DRDRAM.
Real Time - This term is used to describe computer functions that occur immediately.
Remote Access Server (RAS) - A server that is dedicated to handling users that need to gain access to files and print services on the LAN from a remote location. See also: Server and LAN.
Remote Access Services (RAS) - A feature built into Windows NT that enables users to log into an NT-based LAN using a modem, X.25 connection, or WAN link. See also: LAN, WAN, and X.25
Resources - Any hardware or software available to a computer.
RFI - Radio Frequency Interference. Radio frequencies that create noise that interferes with information being transmitted across unshielded copper cable.
RIMM - Rambus Inline Memory Module. A memory module developed by Kingston Technology to package Rambus memory that is smaller than older DIMM modules with different pin connectors. The RIMM module has a 184-pin connector for use in ATX computers, and the SO-RIMM module has a 160-pin connector for use in smaller form-factor computers. See also: RAM, DRAM, DRDRAM, SIMM, and DIMM.
ROM - Read Only Memory. A type of memory prerecorded on a chip that can only be read. This type of memory retains its contents without electricity. See also: PROM, EPROM, EEPROM, and CMOS.
Root Directory - The uppermost directory in a file system. See also: File, and File Management System.
RSI - Repetitive Strain Injury. An injury produced by the continuous repetition of small movements over time.
SDRAM - Synchronous Dynamic Random Access Memory. Memory type that synchronizes itself with the CPU’s bus in order to provide faster transfer rates than standard DRAM. See also: DRAM and RAM.
Search Engine - A type of program that seeks out and indexes documents from the World Wide Web and USENET groups based on specific criteria or “key words”. See also: World Wide Web.
Semiconductor - A material used to make computer chips that is neither a good conductor nor a good insulator. The most common semiconductor materials are silicon and germanium. These materials then have other materials added to them to increase their conductivity. See also: Chip.
Serial - A type of bus that transmits data 1 bit at a time. See also: Bus.
Server - A computer or device on a network that manages network resources. See also: Network and Resource.
Shareware - Copyrighted software that is delivered free of charge, although the author asks a fee from the user if the software is helpful or used often. See also: Software and Freeware.
SIMM - Single Inline Memory Module. A circuit board with a 32-bit data bus that holds memory chips. See also: Circuit Board, DIMM, RIMM, Bus, and Chip.
SLDRAM - Synchronous-Link DRAM. A type of DRAM memory that has a 64-bit bus running at a 200 MHz clock speed where transfers are made twice on each clock cycle, for an effective speed of 400 MHz. See also: DRAM, RAM, and DRDRAM.
SLIP - Serial Line Internet Protocol. A protocol to connect computers to the Internet. See also: PPP and TCP/IP.
Slot - See also: Expansion Slot.
SMIP - Simple Mail Transfer Protocol. An e-mail protocol used by servers to send messages between themselves. SMTP is also used by an e-mail client to retrieve messages from an e-mail server. See also: E-Mail, Protocol, Server, and Client.
SNA - System Network Architecture. Large, complex, feature-rich network architecture developed in the 1970s by IBM. Similar in some respects to the OSI reference model but with a number of differences. SNA essentially is composed of seven layers.
SNMP - Simple Network Management Protocol. A set of protocols that monitors complex networks by sending messages called protocol data units to different parts of the network. SNMP compliant devices then send information about themselves to SNMP requestors. See also: Protocol and Network.
Software - Any type of data or instructions that can be stored electronically.
Software Engineer - A licensed professional engineer who creates the designs for computer programmers to use when creating programs. See also: Programmer and Program.
SPAM - Unsolicited e-mail. See also: E-Mail.
Spreadsheet - Software for arranging values with a defined relationship with each other. See also: Software.
SRAM - Static RAM. A type of RAM that holds its data without being refreshed, for as long as power is supplied to the circuit. See also: RAM.
Standard - An accepted format approved by a recognized organization to define certain aspects of an industry.
Stepper Motor - A type of motor that can be moved in very small, very precise increments.
STP - Shielded Twisted Pair. A type of twisted pair wiring that is shielded against electromagnetic interference. See also: Twisted Pair and UTP.
Streaming Media - A technique for transferring data so it can be processed in a continuous stream in order to display it before the entire file has been transferred.
SVGA - Super Video Graphics Array. A graphics standard giving higher resolution than VGA, and supporting a 16 million color palette.
Synchronous - In terms of data transmission, synchronous means that there is a clock or timing source to keep both the sender and the receiver synchronized.
TCP/IP - Transmission Control Protocol/Internet Protocol. The suite of communications protocols used to connect hosts on the Internet. See also: Protocol, Host, and Internet.
Telecommunications - All type of data transmission.
Token Ring - A type of computer network in which all the computers are arranged in a physical or logical circle. A special bit pattern known as a token travels around the circle. When a computer in the network wishes to send a message, it catches the token, attaches a message to it, and it continues to travel around the network. See also: Network.
Toner - A dry, powdery substance that is electrically charged so that it adheres to a drum, plate, or piece of paper in a laser printer or photocopier charged with the opposite polarity.
Topology - The shape of a communication system such as a LAN. See also: Logical Topology, Physical Topology, and LAN.
Twisted-pair - A type of cabling used for data and voice communications that consists of pairs of copper wires twisted inside an outer jacket. See also: Cable, UTP, and STP.
UNIX - UNIpleXed Information and Computing System. A multiuser, multitasking operating system designed to be used exclusively by programmers. See also Operating System and Programmer.
URL - Uniform Resource Locator. The global addressing system for the World Wide Web. The first part of the address indicates what protocol to use, and the second part specifies the IP address where the resource is located. See also World Wide Web, Protocol, and IP Address.
Upstream - Set of frequencies used to send data from a subscriber to the headend.
USB - Universal Serial Bus. An external bus standard that can connect up to 127 USB devices at transfer rates of up to 180 Mbps. See also: Bus, Serial, and Mb.
USENET - A worldwide bulletin board system that can be accessed through the Internet. See also: BBS and Internet.
UTP - Unshielded Twisted Pair. The most commonly used cabling in modern Ethernet networks. UTP comes in different category ratings depending on whether it is considered voice or data grade and the transmission speed it supports. See also: Twisted Pair, STP, Ethernet, and Network.
Vector-Based - A type of printer font that is a graphics image represented by complicated, outline-oriented images. See also: Font.
VGA - Video Graphics Array. A standard graphics display system for computers that uses an analog signal instead of a digital signal. See also: XGA, Analog, and Digital.
Virtual - Something that is conceptual rather than something that is physical.
Virus - A program that is loaded onto a computer without the knowledge of the user and runs unknowingly and typically maliciously. See also: Program.
VOIP - Voice Over IP. The ability to make telephone calls and send faxes over IP-based data networks while maintaining a suitable QoS. See also: IP, Network, and QoS.
VPN - Virtual Private Network. Uses the Internet as a conduit, through which a secure connection can be established between a remote client and a private LAN, without incurring long distance charges that might result from dialing in to the LAN's server directly. See also: Internet, Client, Server, Host, and LAN.
VRAM - Video RAM. This type of memory is used by video adapters and can be accessed by two different devices at the same time. See also: RAM and WRAM.
VRML - Virtual Realty Modeling Language. A specification for presenting three-dimensional images within Web sites. See also: World Wide Web, Web Page, and Web Site.
Warm Boot - Restarting a computer that is already turned on without first turning it off. See also: Boot and Cold Boot.
Web browser - Software that is used to display web pages and present audio and video to the user. See also: World Wide Web, Web Page, and Web Site.
Web page - A document written in a language of the World Wide Web. See also: World Wide Web, Web Site, HTML, and VRML.
Web portal - A Web site that offers a very broad range of resources from e-mail and Internet service to online shopping. See also: World Wide Web, Web Site, E-Mail, Internet, and ISP.
Web server - A computer that delivers Web pages to computer users on the Internet. See also: World Wide Web, Web Page, Web Site, Internet, and Server.
Web site - A location on the World Wide Web that contains a home page, which is the first document users see when they enter the site. The site might also contain additional documents and files. See also: World Wide Web, Web Page, and Internet.
Windows - A series of GUI operating systems used on IBM compatible personal computers. See also: GUI and Operating System.
Wireless - The ability of an electronic device to communicate with another using the atmosphere as its media. See also: Media.
Wireless Media - Media that carries signals from one computer to another without a permanent tangible physical connection.
Word processor - Software used to perform word processing functions such as writing and editing documents. See also: Software.
World Wide Web (WWW) - A collection of Internet servers that support documents created in a specific format such as HTML to be displayed with a Web browser. See also: Internet, Server, HTML, VRML, and Web Browser.
WRAM - Windows RAM. This is a special type of VRAM that provides even better performance than standard VRAM by supporting two ports for memory exchange. See also: VRML and RAM.
WWW - See also: World Wide Web.
WYSINYG - What You See Is What You Get
XGA - Extended Graphics Array. A graphics standard designed to provide more colors than the older 8514/A standard and allows monitors to be non-interlaced. See also: VGA.
Zone - Collection of all terminals, gateways, and multipoint control units (MCUs) managed by a single gatekeeper. A zone includes at least one terminal, and can include gateways or MCUs. A zone has only one gatekeeper. A zone can be independent of LAN topology and can be comprised of multiple LAN segments connected using routers or other devices.