A+ GLOSSARY 2012-2013

This glossary defines terms related to managing and maintaining a personal computer.

100BaseT An Ethernet standard that operatesat 100 Mbps and uses rwisted-pair cabling.Also called Fast Ethernet. Variations of1O0BaseT are L00BaseTX and 1OOBaseFX.

80 conductor IDE cable An IDE cable that has40 pins but uses 80 wires, 40 of which areground wires designed to reduce crosstalkon the cable. The cable is used by ATN66and higher IDE drives.

802.71^/b/g See IEEE 802.11alblg.

A (ampere or amp) A unit of measurement forelectrical current. One volt across a resistanceof one ohm produces a flow of one amp.

A* Certification A certification awarded byCompTiA (The Computer IndustryAssociation) that measures a PC technician'sknowledge and skills.

access point (AP) A device connected to aLAN that provides wireless communicationso that computers, printers, and otherwireless devices can communicate withdevices on the LAN.

ACPI (Advanced Configuration and PowerInterface) Specification developed by Intel,Compaq, Phoenix, Microsoft, and Toshibato control power on notebooks and otherdevices.

active matrix A type of video display thatamplifies the signal at every intersection inthe grid of electrodes, which enhances thepixel quality over that of a dual-scan passivematrix display.

active partition The primary partition on thehard drive that boots the OS. WindowsVista/XP calis the active partition the"system partition."

adapter address See MAC (Media AccessControl) address.

adapter card A small circuit board inserted inan expansion slot used to communicate

befween the system bus and a peripheraldevice. Also called interface card.

administrator account in Windows VrstaD(Ran account that grants the administratorrights and permissions to all hardware andsofrware resources, such as the right to add,delete, and change accounts and changehardware confi gurarions.

Advanced Options menu A Windows Vrsta/XPmenu that appears when you press F8 when'Windows

starts. The menu can be used totroubleshoot problems when IoadingVindows VistaD(P. In Vista, the menu rscalled the Advanced Boot Options Menu.

adware Sofrware installed onproduces pop-up ads usingthe ads are often based onhabits.

Aero user interface The VistaAlso called Aero glass.

a computer thatyour browser;your browsing

user interface.

AirPort The term Apple uses to describe theIEEE 802.11b standard.

alternating current (AC) Current that cyclesback and forth rather than traveling in onlyone direction. In the United States, the ACvoltage from a standard wall outlet isnormally berween 110 and 115 V. InEurope, the standard AC voltage from awall outiet is 220 V.

ammeter A meter that measures electricalcurrent in amps.

antistatic wrist strap See ground bracelet.

antivirus software Utiliry programs thatprevent infection or scan a system to detectand remove viruses. McAfee AssociatesVirusScan and Norton AntiVirus are twopopular antivirus packages.

APIPA (Automatic Private IP Address) An iPaddress in the address range L69.254.x.x,used bv a comDuter when it can't

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successfully lease an IP address from a DHCPserver.

ASCtr (American Standard Code for InformationInterchange) A popular standard forwriting letters and other characters in binarycode. Originally, ASCII characters were7 bits, so there were L27 possible values.ASCII has been expanded to an 8-bit version,allowing 128 additional values.

ASR (Automated System Recovery) The'Windows

XP process that allows you torestore an entire hard drive volume or logicaldrive to its state at the time the backup of thevolume was made.

AT A form factor, generally no longerproduced, in which the motherboard requiresa fuil-size case. Because of their dirnensionsand configuration, AT systems are difficultto install, service, and upgrade. Also calledfull AT.

AIAPI (Advanced Technology Attachment PacketInterface) An interface standard, part of theIDE/AIA standards, that allows tape drives,CD-ROM drives, and other drives to betreated like an IDE hard drive by the system.

ATX The most common form factor for currentPCs, originally introduced by Intel in 1995.ATX motherboards and cases make bener useof space and resources than did the AT formfactor.

autodetection A feature on newer system BIOSand hard drives that automatically identifiesand configures a new drive in CMOS setup.

autorange mefer A multimeter that sensesthe quantity of input and sets the rangeaccordingly.

Baby AT An improved and more flexibleversion of the AT form factor. Baby AT wasthe industry standard from approximately1.993 to L997 and can fit into some ATXcases.

backup An extra copy of a file, used if theoriginal becomes damaged or destroyed.

bandwidth In relation to anaiog communication,the range of frequencies a cornmunicationschannel or cable can carry. In general use, the

term refers to the volume of data that cantravel on a bus or over a cable stated in bits persecond (bps), kilobits per second (Kbps), ormegabits per second (Mbps). Also called datathroughput or line speed.

bank An area on the motherboard that containsslots for memory modules (typically labeledbank 0 , 1 ,2 , and 3) .

baseline The level of performance expectedfrom a system, which can be compared tocurrent measurements to determine whatneeds upgrading or tuning.

basic disk A way to partition a hard drive, usedby DOS and all versions of

'Windows, that

stores information about the drive in a partitiontable at the beginning of the dr:e. Comparero dynamic disk.

binary numbering system The numbering systemused by computers; it has only two numbers,0 and 1, called binary digits, or bits.

BIOS (basic input/output system) Firmwarethat can control much of a computer's VOfunctions, such as communication with thehard drive and the monitor. AIso called ROMBIOS.

BIOS setup The program in the system BIOSthat can change the values in CMOS RAM.Also called CMOS setup.

bit (binary digit) A 0 or 1 used by the binarynumbering system.

blue screen A Windows Vista/XP errordisplayed on a blue screen that causes thesystem to halt. Also called stop error.

Bluetooth A standard for wireless communica-tion and data synchronization betweendevices, developed by a group of electronicsmanufacturers and overseen by the BluetoothSpecial Interest Group. Bluetooth uses thesame frequency range as IEEE 802.11b butdoesn't have as wide a range.

Blu-ray Disc (BD) An optical disc technologythat uses the UDF version 2.5 file systemand a blue laser beam, which has a shorterwavelength than the beam used by DVD orCD discs. A Blu-ray disc can store more datathan a DVD.

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Boot.ini A Windows XP hidden text file thatcontains information needed to build theboot loader menu.

boot loader menu A startup menu that givesusers the choice of '*'hich operating system toload, such as'Windows Vista or Vindows XP,which are both installed on the same system.creating a dual-boot system.

boot partition The hard drive partition where theVindows VistaD(P OS is stored. The systempartition and boot partition can be differentpartitions.

boot record The first sector of a floppy diskor logical dr ive in a part i t ion; i t containsinformation about the disk or logical drive.On a hard drive, if the boot record is in theactive partition, it 's used to boot the OS. Aisocalled boot sector.

boot sector See boot record.

boot sector virus An infected program that canreplace the boot program with a modified,infected version of the boot command utilities,often causing boot and data retrieval problems.

bootstrap loader A small program at the end ofthe boot record that can be used to boot anOS from the disk or logical drive.

broadband A transmission technique that carriesmore than one rype of transmission on thesame medium, such as cable modem or DSL.

brownouts Temporary reductions in voltage,which can sometimes cause data loss. A/socalled sags.

BTX (Balanced Technology Extended) A formfactor used by motherboards and computercases that was expected to replace ATX. Ithas higher-quality fans, is designed for betterair flow, and has improved structural supportfor the motherboard. The BTX form facrorhas not been widely adopted.

buffer A temporary memory area where data iskept before being written to a hard drive orsent to a printer, thus reducing the number ofwrites to devices.

bus The paths, or lines, on the motherboard onwhich data, insrructions, and electrical powermove from component to component.

bus speed The speed, or frequency, at which thedata on the motherboard moves.

byte A collection of eight bits that's equivalentto a single character. Vhen referring tosystem memor,y, an additional error-checkingbit might be added, making the total nine bits.

cabinet file A file with a .cab extension thatcontains one or more compressed files and isoften used to distribute sofrware on disk. TheExtract command is used to extract files from acabinet file.

cable modem A technology that uses cable TVlines for data transmission, requiring amodem at each end. From the modem,a network cable connects to a NIC in theuser's PC.

capacitor An electronic device that canmaintain an electrical charge for a period oftime and is used to smooth out the flow ofelectrical current. Capacitors are often foundin computer power supplies.

CardBus The latest PCMCIA specification.It improves VO speed, increases the busu,idth to 32 bits, and supports lower-voltagePC Cards, while maintaining backwardcompatibility with earlier standards.

cards Adapter boards or interface cards placedinto expansion slots to expand the functionsof a computer, allowing it to communicatern'ith external devices. such as monitors orspeakers.

CAT A rating for UTP cable. CAT-J e1 |riohercabling is required for Fast Ethernet.

CCITT (Comit6 Consultatif InternationalT6l6graphique et T6l6phonique) An inter-national organization that was responsiblefor developing standards for internationalcommunications. This organization has beenincorporated into the ITU. See also ITU(International Telecommunications Union).

CD (compact disc) An optical disc technologythat uses a red laser beam and can hold uo to700 MB of data.

CD (change directory) command A commandgiven at the command prompt that changesthe default directory. such as CD\Windows.

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CDFS (Compact Disk File System) The 32-bitfile system for CDs and some CD-Rs andCD-R\[s that replaced the older 15-bitmscdex file system used by DOS. See alsoUDF (Universal Disk Format) file system.

CD-R (CD-recordable) A CD drive that canrecord or write data to a CD. The drive mayor may not be multisession, but the data can'tbe erased after it 's wrirten.

CD-RW (CD-rewritable) A CD drive that canrecord or write data to a CD. The data canbe erased and overwritten. The drive may ormay not be mult isession.

chain A group of clusters used to hold asingle file.

child directory See subdirectory.

chip creep A condition in which chips loosenbecause of thermal changes.

chipset A group of chips on the motherboardthat control the timing and flow of data andinstructions to and from the CPU.

CHS (cylinder, head, sector) mode The tradi-tional method by which BIOS reads fromand writes to hard drives by addressing thecorrect cylinder, head, and sector. AIso callednormal mode.

circuit board A computer component, such asthe main motherboard or an adapter board,that has electronic circuits and chips.

clean install An installation of an OS on a newhard drive or a hard drive that has a prevtousOS installed, but it 's performed withoutcarrying forward any settings kept by the oldOS, including information about hardware,sofrware, or user preferences. Also calledfresh installation.

client/server A computer concept whereby onecomputer (the ciient) requests informationfrom another computer (the server).

client/server application An application thathas fwo components. The client softwarerequesrs data from the server software on thesame or another computer.

clock speed The speed, or frequency, expressedin MHz or GHz, that controls activity on the

motherboard and is generated by a crystal oroscillator located on the motherboard.

clone A computer that's a no-name Intel- andMicrosoft-compatible PC.

cluster One or more sectors that constitute thesmallest unit of space on a disk for storingdata. Files are written to a disk as groups ofwhole clusters. Also called file allocation unit.

CMOS (complementary metal-oxidesemiconductor) The technology used tomanufacture microchips. CMOS chips requireless electriciry hoid data longer after theelectriciry is turned off, are slower, and produceless heat than TTL chips. The configuration,or setup, chip is a CMOS chip.

CMOS configuration chip A chip on themotherboard that contains a very smallamount of memory, or RAM, enough to holdconfiguration, or setup) information about thecomputer. The chip is powered by a batterywhen the PC is turned off . Also called CMOSsetup chip or CMOS RAM chip.

CMOS setup The CMOS configuration chip, orthe program in system BIOS that can changethe values in the CMOS RAM.

CMOS setup chip See CMOS configuration chip.

cold boot See hard boot.

combo card An Ethernet card that containsmore than one transceiver, each with a differentport on the back of the card, to accommodatedifferent cabling media.

command prompt window A Windows utilitythat is used to enter multiple commands toperform a variery of tasks.

compact case A type of case used in low-enddesktop systems. Compact cases follow theNLX, LPX, or Mini LPX form factor. Theyare iikely to have fewer drive bays, but theygenerally still provide for some expanslon.Also called low-profile or slimline cases.

compressed drive A drive whose format has beenreorganized to store more data. A compresseddrive is really not a drive at all; it's actuallya rype of file, rypically with a host drivecalled H.

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computer name Character-based host name orNetBIOS name assigned to a computer.

console A centralized location from which torun commonly used tools.

continuity A continuous, unbroken path for theflow of electricity. A continuity test can deter-mine whether internal wiring is still intact orwhether a fuse is good or bad.

conventionalmemory Memoryaddressesbefween 0 and 640K. Also called base memory.

cooler A combination cooling fan and heat sinkmounted on the toD or side of a Drocessor rokeep it cool.

(CPU) central processing unit The heart andbrain of the computer, which receives datainput, processes information, and carries outinstructions . AIso called microorocessor orprocessor.

C-RIMIvI (Continuity RIM 4) A placeholderRIMM module that provides continuity sothat every RIMM slot is filled.

cross-linked clusters Errors caused when morethan one file points to a cluster and the filesappear to share the same disk space, accord-ing to the file allocation table.

crossover cable A cable used to connect fwoPCs into the simplest nerwork possible. AIsoused to connect rwo hubs.

C\rF (compressed volume file) The fiie on thehost drive of a compressed drive that holdsall compressed data.

data bus The lines on the system bus that theCPU uses to send and receive data.

data cartridge A type of tape medium typicallyused for backups. Full-sized data cartridgesare 4 x 5 x % inches. A minicartridge is only3 % x 2 % x % i n c h e s .

data line protector A surge protector designedto work with the telephone line to a modem.

data path size The number of lines on a busthat can hoid data, for example, 8, L5, 32,and 54 lines, which can accommodate 8, 15,32, and 54 bits at a time.

data throughput See bandwidth.

DC (direct current) Current that travels in onlyone direction (the type of electricity providedby batteries). Computer power supplies trans-form AC to low DC.

DC controller A card inside a notebook thatconverts voltage to CPU voltage. Some note-book manufacturers consider the card to be afield replaceabie unit (FRU).

DCE (data communications equipment) Thehardware, usually a dial-up modem, thatprovides the connection between a dataterminal and a communications Iine. See alsoDTE (data terminai equipment).

DDR (Double Data Rate) A type of memorytechnology used on DIMMs that runs atrwice the speed of the system clock,

DDR2 A version of SDRAM that's faster thanDDR and uses less power.

DDR3 A version of SDRAM that is fasterthan DDR2 memory and that can use triplechannels.

default gateway The gateway a computer on anetwork uses to access another nerworkunless it knows to specifically use anothergateway for quicker access to that network.

default printer The printer'Windows prints tounless another printer is selected.

defragment To "optimize" or rewrite a file to adisk in one contiguous chain of ciusters, thusspeeding up data retrieval.

desktop The initial screen displayed when anOS has a GUI interface loaded.

device driver A program stored on the harddrive that teils the computer how tocommunicate with an VO device, such as aprinter or modem.

DHCP (Dynamic Host Configuration Protocol)server A service that assigns dynamic IPaddresses to computers on a network whenthey first access the nerwork.

diagnostic cards Adapter cards designed todiscover and report computer errors andconflicts at POST time (before the computerboots up), often by displaying a number onthe card.

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diagnostic soffware Utility programs that heiptroubleshoot computer systems. Some'Windows

diagnostic utilities are Chkdsk andScandisk. PC-Technician is an example of athird-parry diagnostic program.

differential cable A SCSI cable in which a signalis carried on rwo wires, each carrying voltage,and the signal is the difference berween therwo. Differential signaling provides for errorchecking and improved data integriry.Compare to SE (single-ended) cabie.

digital ceftificate A code used to authenticate thesource of a file or document or to identify andauthenticate a person or organization sendingdata over the Internet. The code is assigned bya certificate authoriry such as VeriSign, andincludes a pubiic key for encryption. A/socalled digital ID or digital signature.

digital ID See digital certificate.

digital signature See digital certificate.

DIMIvI (dual inline memory module) A miniaturecircuit board used in newer computers tohold memory. DIMMs can hold up to 2 GBRAM on a single module.

DIP (dual inline package) switch A switch on acircuit board or other device that can be seton or off to hold configuration or setupinformation.

directory table An OS table that contains fileinformation such as the name, size, time, anddate of iast modification, and cluster numberof the file's beginning location.

Direct Rambus DRAM A memory technologyby Rambus and Intel that uses a narrow, veryfast network-type system bus. Memory isstored on a RIMM module. Also calledRDRAM or Direct RDRAM.

Direct RDRAM See Direct Rambus DRAM.

disk cache A method whereby recently retrieveddata and adjacent data are read into memoryin advance, anticipating the next CPU request.

disk cloning See drive imaging.

disk compression Compressing data on a harddrive to allow more data to be wrirten to thedrive.

disk imaging See drive imaging.

Disk Management A'STindows utility used to

display, create, and format partitions on basicdisks and volumes on dynamic disks.

disk quota A limit placed on the amount of

disk space that's available to users. Requiresa Windows NTFS volume.

disk thrashing A condition that results whenthe hard drive is excessively used for virtualmemory because RAM is full. It dramaticallyslows down processing and can cause prema-

rure hard drive faiiure.

DMA (direct memory access) channel A numberidentifying a channel whereby a device canpass data to memory without involving the

CPU. Think of a DMA channel as a shortcutfor data moving to and from the device andmemory.

DMA transfer mode A transfer mode usedby devices, including the hard drive, totransfer data to memory without involving

the CPU.

DNS server A computer that can find an IP

address for another computer when only the

domain name is known.

docking station A device that receives anotebook computer and provides additionalsecondary storage and easy connection toperipheral devices.

domain In'Windows, a logical group ofnerworked computers, such as those on a

college campus, that share a centraiizeddirectory database of user account informa-

tion and security for the entire domain.

domain name A unique text-based name thatidentifies a nefwork.

DOS box A command window.

dot pitch The distance befween the dots that

the electronic beam hits on a monitor screen.

doze time The time before an Energy Star@ or"green" system reduces 80 percent of its activity.

DPMS (Display Power Management Signaling)Energy Star@ standard specifications thatallow for the video card and monitor to go

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into sleep mode simuitaneously. See also^ 6

t n P r g v \ t r r e

DRAM (dynamic RAM) The most common

rype of system memory, it requires refreshingevery few milliseconds.

drive imaging Making an exact image of a harddrive, including partition information, bootsectors, operating system instaiiation, andapplication software, to replicate the harddrive on another system or recover from ahard drive crash. A/so called disk clonins anddisk imaging.

drop height The height from which a manu-facturer states that its drive can be droppedwithout making the drive unusable.

DSL (Digital Subscriber Line) A telephone linethat carries digital data from end to end andcan be leased from the telephone companyfor individual use. DSL lines are rated at5 Mbps, about 50 times faster than 16'o,,lo'telephone lines.

DTE (data terminal equipment) Both thecomputer and a remote terminal or othercomputer to which it's attached. See alsoDCE (data communications equipment).

dual boot The ability to boot using either ofrwo different OSs, such as'Windows Vistaand Windows XP.

dual channel A motherboard feature thatrmproves memory performance by providingrwo 54-bit channels berween memory and thechipset. DDR, DDR2, and DDR3 DIMMScan use dual channels.

dual core A processor package that contarnstwo core processors, thus supporting fourinstructions at once.

dual-scan passive matrix A type of video displaythat's less expensive than an acrive-matrixdisplay and does not provide as high-qualiry animage.

'With dual-scan display, two columns of

electrodes are activated at the same time.

dual-voltage CPU A CPU that requires rwodifferent voltages, one for internal processingand the other for VO processing.

DVD (digital video disk or digital versatile disk)A faster, larger CD format that can read older

CDs, store more than 8 GB of data, and holdfull-length motion picure videos.

dynamic disk A way to partirion one or morehard drives, introduced with'Windows 2000,in which information about the drive isstored in a database at the end of the drive.Compare to basic disk.

dynamic IP address An assigned IP address usedfor the current session only.

'V/hen the session

is terminated, the IP address is returned tothe list of available addresses.

dynamic volume A volume rype used withdynamic disks for which you can change thesize of the volume after you have created it.

ECC (error-correcting code) A chipset feafure on amotherboard that checks the integrity of datastored on DIMMs or RIMMs and can correctsingle-bit errors in a b1te. More advanced ECCschemas can detect. but not correct. double-biterrors in a b1te.

ECHS (extended CHS) mode See Iarge mode.

ECP (Extended Capabilities Port) A bidirectionalparallel port mode that uses a DMA channelto speed up data flow.

EDO (extended data out) A rype of RAM thatcan be 10 percent to 20 percent faster thanconventional RAM because it eliminates thedelay before it issues the next memory address.

EEPROM (electrically erasable programmableROM) A type of chip in which highervoltage can be applied to one of the pins toerase its previous memory before a newinstruction set is electronically written.

EFS (Encrypted File System) A way to use akey to encode a file or foider on an NTFSvolume to protect sensit ive data. Becauseit 's an integrated system service, EFS istransparent to users and applications anddifficult to attack.

EIDE (Enhanced IDE) A standard for managingthe interface between secondary storagedevices and a computer system. A system cansupport up to six serial ATA and parallelATA EIDE devices or up to four parallel ATAIDE devices, such as hard drives, CD-ROMdrives. and Zip dr ives.

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emergency startup disk (ESD) See rescue disk.

EMI (electromagnetic interference) A magneticfield produced as a side effect from the flowof electriciry. EMI can cause corrupted datain data lines that aren't properly shielded.

encryption The process of putting readable datainto an encoded form that can be decoded (or

decrypted) only through use of a key.

Energy Star@ "Green" systems that satisfy the EPArequirements to decrease the overall consump-tion of electricity. See also Green Standards.

enhanced BIOS A system BIOS that has beenwritten to accommodate large-capacity drives(more than 504 MB, usually in the gigabyterange).

EPP (Enhanced Parallel Port) A parallel portthat allows data to flow in both directrons(bidirectional port) and is faster than originalparallel ports on PCs that allowed communi-cation oniy in one direction.

EPROM (erasable programmable ROM) A rypeof chip with a speciai window that aliows thecurrent memory contents to be erased withspecial ultraviolet light so that the chip canbe reprogrammed. Many BIOS chips areEPROMs.

error correction The capabiliry of a modem toidentify transmission errors and then auto-matically request another transmission.

escalate When a technician passes a customer'sproblem to higher organizational levelsbecause he or she cannot solve the problem.

ESD (electrostatic discharge) Another name forstatic electricity, which can damage chips anddestroy motherboards, even though it mightnot be felt or seen with the naked eye.

ESD (emergency startup disk) See rescue disk.

Ethernet The most popular LAN architecturethat can run at 10 Mbps (ThinNet orThickNet), 100 Mbps (Fast Ethernet), or1 Gbps (Gigabit Ethernet).

Event Viewer (Evenwwr.msc) A'Windows tooluseful for troubleshooting problems withWindows, applications, and hardware. Itdisplays logs of significant events.

expansion bus A bus that doesn't run in syncwith the system clock.

expansion card A circuit board inserted into aslot on the motherboard to enhance thecomputer's capabiliry.

expansion slot A narrow slot on the mother-board where an expansion card can beinserted. Expansion slots connect to a bus onthe motherboard.

extended partition The only partition on a harddrive that can contain more fhan one logicaldrive.

external SAIA (eSAIA) A standard for externaldrives based on SATA that uses a specialexternal shielded SATA cable up to twometers long.

faceplate A metal plate that comes with themotherboard and fits over the ports to createa weli-fitted enclosure around them.

Fast Ethernet See 100BaseT.

FAT (file allocation table) A table on a harddrive or floppy disk that tracks the clustersused to contain a file.

FATI2 The 12-bit-wide, one-column fileallocation table for a floppy disk, containinginformation about how each cluster or fileallocation unit on the disk is currently used.

fault tolerance The degree to which a systemcan tolerate failures. Adding redundantcomponents, such as disk mirroring or diskduplexing, is a way to build in fault toierance.

file allocation unit See cluster.

file extension A three-character portion of thefilename used to identify the file type. Incommand lines, the file extension follows thefilename and is separated from it by aperiod, such as Msd.exe, with exe being thefile extension.

filename The first part of the name assignedto a file. In DOS, the filename can be nomore than eight characters and is followed bythe file extension. In Vindows, a filenamecan be up to 255 characters.

file system The overall structure that an OSuses to name) store, and organize files on a

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disk. Examples of file sysrems are FAT32 andNTFS.

file virus A virus rhat inserts virus code rnroan executable program file and can spreadwherever that program runs.

firewall Hardware or soffware that protects acomputer or network from unauthorized access.

FireWire See IEEE 1394.

firmware Sofuware permanently stored in a chip.The BIOS on a motherboard is an examole offirmware.

flash ROM ROM that can be reprogrammed orchanged without replacing chips.

flat panel monitor A desktop monitor that usesan LCD panel.

FlexAIX A version of rhe ATX form factorthat allows for maximum flexibility in thesize and shape of cases and motherboards.FlexATX is ideai for cusrom sysrems.

flow control When using modems, a method ofcontrolling the flow of data to adjust forproblems wirh dara rransmission. Xon/Xoff isan example of a flow control protocol.

folder Seesubdirectory.

forgotten password floppy disk A'S7indows Xpdisk created to be used in case the user forgetsthe user account password to the system.

form factor A set of specifications on the size,shape, and configuration of a computerhardware component, such as a case) powersupply, or morherboard.

f<lrmatting Preparing a hard drive volume orfloppy disk for use by placing tracks andsectors on its surface to store information(for example, the FORMAT A: command).

FPT (forced perfect terminaror) A rype of SCSIactive terminator that includes a mechanismto force signal termination to the correctvoltage, eliminating most signal echoes andinterference.

FQDN (fully qualified domain name) A hostname and a domain name, such as jsmith.amazon. com. Sometimes loosely referred to asa domain name.

fragmentation The distribution of data files ona hard drive or floppy disk so that rhey arestored in noncontiguous clusters.

fragmented file A file that has been wrimen rodifferent portions of the disk so thar ir's notin contiguous clusters.

FRU (field replaceable unit) A component ina computer or device that can be replacedwith a new component without sending thecomputer or device back to the manufacturer.Examples: power supply, DIMM, morher-board, floppy disk drive.

FTP (File tansfer Protocol) The prorocol usedto transfer files over a TCP/P nerwork sothat the file doesn't need to be converfed toASCII format before transferrins ir.

full AT See Nl.

gateway A computer or other device thatconnects nefworks.

GDI (Graphics Device Interface) A'Windows 9xcomponent that controls screens, graphics,a n d n r i n t i n o

GHz (gigahertz) 1000 MHz, or one bill ioncycles per second.

Gigabit Ethernet The newest version ofEthernet. Gigabit Ethernet supports rares ofdata transfer up to 1 gigabit per second butisn't wideiy used yet.

global user account Sometimes called adomain user account, the account isused at the domain level, created by anadministrator, and stored in the SAM(Security Accounts Manager) database on a'Windows

2000 or Windows 2003 domaincontroller.

GPF (General Protection Fault) A Windowserror that occurs when a program attempts toaccess a memory address that isn't availabieor is no longer assigned to it.

graphics accelerator A rype of video card withan on-board processor that can substantiallyincrease speed and boost graphicai and videoperformance.

graphics DDR (G-DDR), graphics DDR2, graphicsDDR3 Types of DDR, DDR2, and DDR3

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memory specifically designed to be used ingraphics cards.

Green Standards A computer or device thatconforms to these standards can go into sleepor doze mode when not in use, thus savingenergy and helping the environment. Devicesthat carry the Green Star or Energy Star@comply with these standards.

ground bracelet An antistatic strap you weararound your wrist that's attached to the com-puter case, grounding mat, or another groundso that ESD is discharged from your bodybefore you touch sensitive components insidea computer. Also called antistatic strap,ground strap, or ESD bracelet.

group profile A group of user profiles. Allprofiles in the group can be changed bychanging the group profile.

guard tone A tone that an answering modemsends when it first answers the phone to tellthe calling modem that a modem is on theother end of the iine.

Guest user A user who has limited permissionson a system and can't make changes to it.Guest user accounts are intended for one-timeor infrequent users of a workstation.

handshaking '$fhen

rwo modems begin tocommunicate, the initial agreement made asto how to send and receive data.

hard boot Restart the computer by turning offthe power or by pressing the Reset button.Also called cold boot.

hard copy Output from a printer to paper.

hard drive The main secondary storage deviceof a PC is a smali case containing magnetic-coated platters that rotate at high speed.

hard drive standby time The amount of timebefore a hard drive shuts down to conserveenergy.

hardware The physical components thatconstitute the computer system, such asthe monitor, keyboard, motherboard, andprinter.

hardware address See MAC (Media AccessControl) address.

hardware cache A disk cache contained inRAM chips built right on the disk controller.Also called buffer.

hardware interrupt An event caused by ahardware device signaling the CPU that itrequires service.

hardware profile A set of hardware configura-tion information that Windows keeps in theRegistry.

'S7indows can maintain more than

one hardware profile for the same PC.

HCL (Hardware Compatibility List) The list ofall computers and peripheral devices that havebeen tested and are officially supported by'$Tindows

2000DQ (see wuu.micro sott.com/wh dc/h cl/ default.msp x).

head The top or bottom surface of one platteron a hard drive. Each platter has rwo heads.

heat sink A piece of metal, with cooling fans,that can be attached to or mounted on anintegrated chip (such as the CPU) to dissipateheat.

hexadecimal (hex) notation A numbering systemthat uses 15 digits, the numerals 0 to 9, andthe letters A to F. Hexadecimal notation tsoften used to dispiay memory addresses.

hibernation A notebook OS feature thatconserves power by using a small trickle ofelectriciry. Before the notebook begins tohibernate, everything currently stored inmemory is saved to the hard drive. When thenotebook is brought out of hibernation, openapplications and their data are returned totheir state before hibernation.

hidden file A file that isn't displayed in a directorylist. Vhether to hide or display a file is one ofthe fiie's artributes the OS keeps.

highJevel formatting Formaning performed bythe'STindows Format program, the'Windowsinstallation program, or the Disk Managementutiliry. The process creates the boot record,file system, and root directory on thevolume or logical drive and makes the drivebootable. Also called operating systemformatting.

hive Physical segment of the 'Windows

Vista/XPRegistry that's stored in a fiie.

GLossARY I 5 1 9

HMA (high memory area) The first 64K ofextended memory.

host Any computer or other device on anefwork that has been assiened an IP address.AIso called node.

host adapter The circuit board that controls aSCSI bus support ing as many as 7 or 15separate devices. The host adapter controlscommunication between the SCSI bus andthe PC.

host bus See system bus.

host name A name that identifies a computer,printer, or other device on a network.

hot-pluggable See hot-swappable.

hot-swappable A device that can be plugged intoa computer while it's turned on and thecomputer senses the device and configures itwithout rebooting, or the device can beremoved without an OS error. A/so calledhn t -n l t r ooeh le

HTML (Hypertext Markup Language) A markupianguage used for hypertext documents on the'World

Wide Web. This language uses tags toformat the document, create hyperlinks, andmark iocations for graphics.

HTTP (Hypertext Transfer Protocol) Theprotocol used by the World'S7ide Web.

HTTPS (HTTP secure) A version of HTTP thatincludes data encryption for security.

hub A network device or box that provides acentral location to connect cables.

hypertext Text that contains iinks to remotepoints in the document or to other files,documents, or graphics. Hypertext is createdby using HTML and is commonly used onWeb sites.

Hyper-Threading The Intel technology thatallows each logical processor within theprocessor package to handle an individualthread in parallel with other threads beinghandled by other processors within thepackage.

Hz (hertz) Unit of measurement for frequency,caicuiated in terms of vibrations. or cycles

per second. For example, for 16-bit stereosound, a frequency of 44,000 Hz is used. Seealso MHz (megahertz).

i.Link See IEEE 1394.

I /O addresses Numbers used by devices andthe CPU to manage communicat ionbetween them. A/so called ports or portaddresses.

VO controller card An older card that cancontain serial, parailel, and game ports andfloppy drive and IDE connectors.

ICF (Internet Connection Firewall) Vindowssoftware designed to protect a PC fromunauthorized access from the Internet:updated to Vindor,l.s XP Firewall in Servrcen ! ^racK /-.

ICS (lnternet Connection Sharing) A'Windowsutility that uses Network Address Translation(NAT) and acts as a prorT server to managetwo or more computers connected to theInternet.

IDE (Integrated Drive Electronics or IntegratedDevice Electronics) A hard drive with a diskcontroller integrated into the drive, eliminat-ing the need for a controller cable and thusincreasing speed and reducing price. See alsoEIDE (Enhanced IDE).

IEEE (Institute of Electrical and ElectronicsEngineers) A nonprofit organization thatdevelops standards for the computer andelecrronics ind ustr ies.

IEEE 802.1[alh/g/n IEEE specifications forwireless communication and data synchroniza-tion. A/so called \7i-Fi. Apple Computer'sversions of 802.11 standards are cal ledAirPort and AirPort Extreme.

IEEE 1284 A standard for parallel ports andcables developed by the Institute for Electricaland Electronics Engineers and supported bymany hardware manufacturers.

IEEE 1394 Standards for an expansion busthat can also be configured to work as a localbus. It's expected to replace the SCSI bus,providing an easy method to install andconfigure fast VO devices. Also calledFireWire and i.Link.

G LO SSA RY

IEEE 1394.3 A standard, developed by the1394 Trade Association, designed for peer-to-peer data transmission. It allows imagingdevices to send images and photos directly toprinters without involving a computer.

infestation Any unwanted program that'stransmitted to a computer without the user'sknowledge and designed to do varyingdegrees of damage to data and software.There are a number of different types ofinfestations, including viruses, Trojan horses,worms, and logic bombs.

information (.infl file Text file with an .inf fileextension, such as Msbatch.inf, that containsinformation about a hardware or sofrwarernstallation.

infrared transceiver A wireless transceiver thatuses infrared technology to support wirelessdevices, such as keyboards, mice, and printers.A motherboard might have an embeddedinfrared transceiver, or the transceiver mightplug into a USB or serial port. The technologyis defined by the Infrared Data Association(IrDA). Also called IrDA transceiver orinfrared port.

initialization files Configuration information filesfor Windows. System.iru is one of the mostimportant Windows 9x irutialization files.

ink-jet printer A type of ink dispersion printerthat uses cartridges of ink. The ink is heatedto a boiling point and then ejected onto thepaper through tiny nozzles.

intranet A private network that uses TCP/IPprotocols.

IP address A 32-bit address consisting of fournumbers separated by periods, used touniquely identify a device on a nefwork thatuses TCP/IP protocols. The first numbersidentify the network; the last numbers identifya host. An example of an IP address is206.96 .103s . I 14 .

IIDA transceiver See infrared transceiver.

IRQ (interrupt request) line A line on a busassigned to a device that's used to signal theCPU for servicing. These lines are assigned areference number (for example, the normalIRQ for a printer is IRQ 7).

ISA (Industry Standard Architecture) slot Anolder slot on the motherboard used forslower VO devices, which can support an8-bit or a 15-bit data path. ISA slots havemostly been replaced by PCI slots.

ISDN (tntegrated Services Digital Network)A digital telephone line that can carry dataat about five times the speed of regulartelephone lines. Two channels (telephonenumbers) share a single pair of wires.

ISP (Internet service provider) A commercialgroup that provides Internet access for amon*ily fee. AOL, Earthlink, and CompuServeare large ISPs.

ITU (International Telecommunications Union)The international organization responsiblefor developing international standards ofcommunication. Formerly CCITT.

JPEG (Joint Photographic Experts Group)A graphical compression scheme that allowsusers to control the amount of data that'saveraged and sacrificed as file size is reduced'It's a common Internet fiie format. Most

JPEG f i les have a . ipg extension.

jumper Two wires that stick up side by sideon the motherboard and are used to holdconfiguration information. The jumper rsconsidered closed if a cover is over the wrresand open i f the cover is missing.

k.y In encryption, a secret number or code usedto encode and decode data. In Windows, asection name of the'S7indows Registry.

keyboard A common input device throughwhich data and instructions can be typed intocomputer memory.

LAN (local area network) A computer nefworkthat covers only a small area, usualiy withinone building.

laptop computer See notebook.

large-capacity drive A hard drive larger than504 MB.

large mode A mode of addressing informationon hard drives that range from 504 MB to8.4 GB by translating cylinder, head, andsector information to break the 528 MB hard

G L 0 S S A R Y I 521

drive barrier. Also called ECHS (extendedCHS) mode.

Last Known Good Configuration In'VTindows,Registry settings and device drivers that werein effect when the computer last bootedsuccessfully. These sertings can be restoredduring the startup process to recover fromerrors during the previous boot.

LBA (logical block addressing) mode A modeof addressing information on hard drives inwhich the BIOS and operating system viewthe drive as one long linear iist of LBAs oraddressable sectors, permitting drives to belarger than 8.4 GB. (LBA 0 is cylinder 0,head 0, and sector L.)

LIF (low insertion force) socket A socket thatrequires the installer to manually apply aneven force over the microchip when insertingthe chip into the socket.

Limited users 'Windows

user accounts; theyhave read-write access only on their ownfolders, read-only access to most systemfolders, and no access to other users'data.

line speed See bandwidth or modem speed.

Lmhosts A text file in the'Windows folder thatcontains NetBIOS names and their associatedIP addresses. This file is used for name resolu-tion on a NeIBEUI nefwork.

local bus A bus that operates at a speedsynchronized with the CPU frequency. Thesystem bus is a local bus.

local VO bus A local bus that provides VO deviceswith fast access to the CPU.

local printer A printer connected to a computerby way of a port on the computer. Comparefo network printer.

local profile A user profile srored on a localcomputer that can't be accessed from anothercomputer on the network.

local user account A user account that appliesonly to a local computer and can't be used toaccess resources from other computers on thenerwork.

logical drive A portion or all of a hard driveparci t ion that the operar ing system rreats

as though it were a physical drive. Eachlogical drive is assigned a drive letter, suchas C, and contains a f i le system. Also cal ledvolume.

logical geometry The number of heads, tracks,and sectors that the BIOS on the hard drivecontroller presenrs ro the system BIOS andthe OS. The logical geometry doesn'r consisrof the same values as the physical geomerry,although calculations of drive capaciry yieldthe same results.

lost allocation units See lost clusrers.

lost clusters File fragmenrs that, according tothe file allocation table, contain data thatdoesn't belong to any file. The CHKDSK/Fcommand can free these fragments. A/socalled iost allocation units.

lowlevel formatting A process (usually performedat the factory) that electronically creates thehard drive tracks and sectors and tests for badspots on the disk surface.

low-profile case See compact case.

LPX A form factor in which expansion cardsare mounted on a riser card that plugs into amotherboard. The expansion cards in LPXsystems are mounted parallel to the mother-board instead of perpendicular to it, as in ATand ATX systems.

MAC (Media Access Control) address A 5-bytehexadecimal hardware address uniqueto each NiC card and assigned by the manu-facturer. The address is often printed on theadapter. An example is 00 00 0C 08 2F 35.Also called physical address, adapter address,or hardware address.

main board See motherboard.

master file table (MFT) The database used bythe NTFS file system to track rhe contents ofa logical drive.

MBR (Master Boot Record) The first secor ona hard drive, which contains the partitiontable and a program BIOS used ro boor anOS from the drive.

MDRAM (MultiBank DRAM) A type of videomemory that's faster than VRAM andsfifuAM but can be more economical because

G L O S S A R Y

it can be installed on a video card in smaller

increments.

memory Physical microchips that can hold data

and programming, located on the mother-

board or expansion cards.

memory address A number assigned to each

byte in memory. The CPU can use memory

addresses to track where information is

stored in RAM. Memory addresses are

usually displayed as hexadecimal numbers

in segment/offset form.

memory bus See system bus.

memory dump The contents of memory saved

to a file at the time an event halted the system.

Support technicians can analyze the dump fiie

to help understand the source of the problem.

memory extender For DOS and'STindows 9x, a

device driver named Himem.sys that manages

RAM, giving access to memory addressesabove 1 MB.

memory paging In \7indows, swapping blocks

of RAM to an area of the hard drive to serve

as virtual memory when RAM is low.

memory-resident virus A virus that can stay

lurking in memory even after its host program

is terminated.

MHz (megahertz) One million Hz, or one

million cycles per second' See also Hz (hertz)'

microATX A recent version of the ATX form

factor. MicroMX addresses some new

technologies that have been developed since

the original introduction of ATX.

MicroDIMM A type of memory module used

on notebooks that has L44 pins and uses a

64-bit data path.

microprocessor See CPU (central processing urut)'

Mini PCI The PCI industry standard for desk-

top computer expansion cards, applied to a

much smaller form factor {or notebook

expansion cards.

Mini-ATX A smaller ATX board that can be used

with reguiar ATX cases and power suppiies.

minicartridge A tape drive cartridge that is only

3 x 2 inches. It's small enough to allow rwo

drives to fit into a standard S-inch drive bay of

a PC case.

Mini-LPX A smaller version of the LPX

motherboard.

MMC (Microsoft Management Console) A utiiity

to build customized consoles. These consoles

can be saved to a file with an .msc file

extenslon.

MMX (Multimedia Extensions) Multimedia

instructions built into lntel processors to add

functionality such as better processing of multi-

media, SIMD support, and increased cache'

modem From the words "modulate-demodulate,"

a device that modulates digital data from a

computer to an analog format that can

be s.rrt over telephone lines' and then

demodulates it back into digital form.

modem speed The speed at which a modem can

transmit data along a phone iine, measured in

bits per second (bps). A/so called bandwidth

or line speed.

monitor The most commonly used output device

for displaying text and graphics on a computer'

motherboard The main board in the computer'

The CPU, ROM chiPs, SIMMs, DIMMs,

RIMMs, and interface cards are plugged into

the motherboard. A/so called the main board

or system board.

motherboard bus See sYstem bus'

motherboard mouse See PSl}-compatible mouse'

mouse A pointing and input device that ailou's

users to move a cursor around a screen and

select programs with the click of a button'

MP3 A method to compress audio files that

uses MPEG level 1. It can reduce sound files

to as low as a 1:24 ratio without losing much

sound quality.

MPEG (Moving Pictures Experts Group) A

processing-intensive standard for data

compression for motion pictures that tracks

movement from one frame to the next and

stores only the data that has changed.

MSDS (material safety data sheet) A document

that expiains how to handle substances such

G L O S S A R Y

as chemical solvents; it includes informationsuch as physical data, toxicity, heaith effe*s,first aid, storage, disposai, and spillprocedures.

multicasting A process in which a message issent by one host to multiple hosts, such aswhen a video conference is broadcasr roseverai hosts on the Internet.

multimeter A device used to measure thecomponents of an electrical circuit. The mostcommon measurements are volcage, current,and resistance.

multiplier The factor by which the bus speed orfrequency is multiplied ro get the CpU clockspeed.

multiscan monitor A monitor that can workwithin a range of frequencies and, therefore,can work with different srandards and videocards. It offers a variery of refresh rates.

name resolution The process of associating aNeIBIOS name or host name to an Ip address.

NAT (Network Address Translation) A processthat converts private IP addresses on a LANto the prory server's IP address before a datapacket is sent over the Internet.

NeIBEIII (NeIBIOS Extended User lnterface)A proprietary, and outdated Microsofrnefworking protocol used only by Vindows-based systems, and limited to LANs becauseit doesn't support routing.

NeIBIOS (Nerwork Basic Input/Output System)An API protocol used by some applicarionsto communicate over a NeIBEUI nefwork.NeIBIOS has largely been replaced by'Sfindows

Sockets over a TCP/IP nefwork.

nefwork adapter See NIC (nerwork interfacecard).

nefwork drive map Mounting a drive, such asdrive E, to a computer that's actually harddrive space on another host computer on thenetwork.

nefwork printer A printer that any user on thenerwork can access, through its own nerworkcard and connection ro the nefwork, througha connection to a stand-alone print server, or

through a connection to a computer as alocai printer, which is shared on the nerwork.Compare to local printer.

MC (network interface card) An exDansroncard that plugs into a computer', -other-board and provides a porr on rhe back of rhecard to connect a PC to a nefwork. A/socalled nerwork adapter.

NLX A low-end form factor that's similar to LpXbut provides more support for current andemerging processor technologies. NLX wasdesigned for flexibility and efficiency of space.

node See host.

noise An extraneous, unwanted signal, oftenover an analog phone line, that can causecommunication interference or transmissionerrors. Possible sources are fluorescent light-ing, radios, TVs, lightning, or bad wiring.

nonvolatile Refers to a kind of RAM that'sstable and can hold data as long as elecriciryis powering the memory.

normal mode See CHS (cylinder, head, secror)mode.

North Bridge That portion of the chipset hubthat connects faster VO busses to the sysrembus. Compare to South Bridge.

NOS (nerwork operating system) An operatingsystem that resides on the controiling compurerin the network. The NOS controls what soft-ware, data, and devices users on the networkcan access. Examples of an NOS are NovellNet'Ware and Windows 2000 Server.

notebook A portable computer designed fortravel and mobility. Notebooks use the sametechnology as desktop PCs, with modifica-tions for conserving voltage, taking up lessspace, and operating while on the move. ,4/socalled laptop computer.

NTFS (NT File System) The file sysrem for the'STindows 2000lXP operating systems. NTFS

can't be accessed by other operating sysrems,such as DOS. It provides increased reliabiliryand security compared with other merhods oforganizing and accessing files. There areseveral versions of NTFS thar mieht becompatible.

G L O S S A R Y

Nttdr (NT Loader) In'Windows, the OS loader

used on Intel systems.

NTVDM (NT virtual DOS machine) An

emulated environment in which a 16-bit DOS

application resides in Windows with its own

memory space or WO\7 (Win16 on'Sfin32).

null modem cable A cable that allows rwo datatermrnal equipment (DTE) devices to communi-cate; the transmit and receive wires are cross-

connected, and no modems are necessary'

octet Term for each of the four 8-bit numbers

that make up an IP address' For example, the

IP address 206.96.1'03.114 has four octets.

ohm (O) The standard unit of measurement for

electrical resistance. Resistors are rated in ohms.

on-board ports Ports that are directly on the

motherboard, such as a built-in keyboardport or on-board serial Port.

operating system formatting See high-levelformatting.

OS (operating system) Software that controis a

computer. An OS controis how systemresources are used and provides a userinterface, a way of managing hardware and

soffware, and ways to work with files.

overclocking Running a processor at a higher

frequency than is recommended by the manu-

facturet which can result in an unstable system.

PL connector Power connection on an ATX

motherboard.

page fault An OS interrupt that occurs when

the OS is forced to access the hard drive to

satisly the demands for virtual memory.

page file See swap file.

Pagefile.sys The Windows swaP file.

page-in The process in which the memorymanager goes to the hard drive to return the

data from a swap file to RAM.

page-out The process in which, when RAM is

full, the memory manager moves a page to

the swap file.

pages 4 KB segments in which'Sfindows 20001

XP allocates memory.

parallel port A female 25-pin port on a

computer that can transmit data in parallel,

8 bits at a time, and is usually used with aprinter. The names for parallel ports areLPT1 and LPT2.

parity An error-checking scheme in which a

ninth, or "pariry" bit is added. The value of

the parity bit is set to 0 or L to provide an

even number of 1s for even parity and an oddnumber of 1s for odd parity'

pariry error An error that occurs when the

number of Ls in the byte isn't in agreementwith the expected number.

parity memory Nine-bit memory in whichthe ninth bit is used for error checking.A SIMM part number with 35 in it (4 x 9 bits)

is parity. Older PCs almost always use parity

chips.

pafiition A division of a hard drive that can be

used to hold logical drives.

partition table A table at the beginning of the

hard drive that contains information about

each partition on the drive. The partition

table is contained in the Master Boot Record.

passive terminator A rype of terminator for

singie-ended SCSI cables. Simple resistorsprovide termination of a signal. Passive terml-

nation isn't reliabie over long distances and

should be used only with narrow SCSI.

PATA (parallel ATA) An older IDE cablingmethod that uses a 40-pin flat data cable or

an 80-conductor cable and a 40-pin IDE con-

nector. See also SAIA (serial ATA).

patch An update to sofrware that corrects an

error, adds a feature, or addresses securityissues. Also called update or service pack.

patch cable A network cable used to connect a

PC to a hub.

path A drive and list of directories pointing to a

file, such as C:\Windows\command.

PC Card A credit-card-size adapter card that

can be slid rnto a slot in the side of many note-

book computers and is used for connecting to

modems, nerworks, and CD-ROM dnves.

Also called PCMCIA Card.

G L O S S A R Y I 525

PC Card slot An expansion slor on a notebookcomputer into which a PC Card is inserted.Also called PCMCIA Card slot.

PCI (Peripheral Component Interconnect) busA bus common on Pentium computers thatruns at speeds up to 33 MHz or 65 MIFrz,with a 32-bit-wide or 54-bit-wide data path.PCI-X, released in September 1999, enablesPCI to run at 133 MHz. For some chipsers, itserves as the middle layer berween rhememory bus and expansion buses.

PCI Express (PCIe) The latest evolution of PCI,which is not backward-comparible witheariier PCI slots and cards. PCIe slots comein several sizes, including PCIe x1, PCIe x4,PCIe x8. and PCIe x15.

PCMCIA (Personal Computer Memory CardInternationalAssociation) Card SeePC Card.

PCMCIA Card slot See PC Card slot.

PDA (personal digital assistant) A small handheldcomputer that has its own operating systemand applications.

peer-to-peer network A nefwork of compurersthat are ail equals, or peers. Each computerhas the same amount of authoriry andeach can act as a server to the othercomputers.

peripheral devices Devices thar communicatewith the CPU but aren't locared directly onthe motherboard, such as the monitor, floppydrive, printer, and mouse.

permissions Refer to the user accounts or usergroups allowed to access data. Varyingdegrees of access can be assigned to a folderor file, including full control, write, delete,and read-only.

PGA (pin grid array) A feature of a CPU socketwhereby the pins are aiigned in uniform rowsaround the socket.

physical address See MAC (Media AccessConrrol) address.

physical geometry The actual layout of heads,tracks, and sectors on a hard drive. See alsologicai geometry.

PIF (program information file) A file used by'Windows to describe the environment for a

DOS program to use.

Ping (Packet Internet Groper) A'Windowsand UNIX command used to troubleshootnerwork connections. It verifies that the hostcan communlcare with another host on thenerwork.

pinout A description of how each pin on a bus,connection, plug, slot, or socket is used.

PIO (Programmed VO) transfer mode A transfermode that uses the CPU to transfer data fromthe hard drive to memory. PIO mode is slowerthan DMA mode.

pixel A small spot on a fine horizontal scanline. Pixels are illuminated to create an imaeeon the monitor.

polling A process by which the CPU checks thestatus of connected devices to determinewhether they are ready to send or receive data.

port As applied to services running on acomputer, a number assigned to a process ona computer so that the process can be foundby TCP/IP. Also called a porr address or porrnumber. It is also another name for an VOaddress. See also VO address. A physical con-nector, usually at the back of a computer, thatallows a cable from a peripheral device, suchas a printer, mouse, or modem, ro beattached.

port address See port or VO addresses.

port number See port.

port replicator A device designed to connectto a notebook computer to make it easyto connect the notebook to peripheraldevices.

port settings The configuration parameters ofcommunication devices such as COM1,COM2, or COM3, inciuding iRQ settrngs.

POST (power-on self test) A self-diagnosticprogram used to conduct a simple test of theCPU, RAM, and VO devices. The POSTis performed by startup BIOS when thecomputer is first turned on and is stored inROM-BIOS.

G LO 5SA RY

power scheme A feature of 'Windows

XPsupport for notebooks that allows users tocreate groups of power settings for specificsets of conditions.

power supply A box inside the computer casethat supplies power to the motherboard andother installed devices. Power suppliesprovide 3.3, 5, and 1.2 volts DC.

power-on password A password that a computeruses to control access during the boot process.

PnP (Plug and Play) A standard designed to makeinstalling new hardware devices easier byautomatically configuring them to eliminatesystem resource conflicts (such as IRQ orVO address conflicts). PnP is supported byVindows 9x,'Windows 2000, andWindows XP.

primary partition A hard disk partition that cancontain only one logical drive.

primary storage Temporary storage on themotherboard used by the CPU to process dataand rnstructions. Memory is consideredprimary storage.

printer A peripheral output device that producesprinted output to paper. Different typesinclude dot matrix, ink-jet, and laser printers.

printer maintenance kit A kit purchased from aprinter manufacturer that contains the parts,tools, and instructions needed to performroutine printer maintenance.

private IP address An IP address used on a privateTCP/IP nerwork that's isolated from theInternet.

process A running instance of a programtogether with the program resources. Morethan one process can be running for a pro-gram at the same time. One process for aprogram happens each time the program isloaded into memory or runs.

processor See CPU (central processing unit).

processor speed The speed, or frequency, at whichthe CPU operates. Usually expressed in GFIz.

product activation The process that Microsoftuses to prevent software piracy. For example,after \Tindows XP is activated for a particular

computer, it can't be installed on anothercomputer.

program A set of step-by-step instructions to acomputer. Some are burned directly intochips, whereas others are stored as programfiles. Programs are written in languages suchas BASIC and C+-r.

program file A file containing instructionsdesigned to be carried out by the CPU.

protected mode An operating mode thatsupports preemptive muititasking. The OSmanages memory and other hardware devices,and programs can use a 32-bit data path. Alsocalled 32-bit mode.

protocol A set of rules and standards that fwoentities use for communication.

Protocol.ini A Windows initialization filecontaining nefwork configuration information.

proxy server A server that acts as an intermediarybefween another computer and the lnternet.The proxy server substitutes its own IP addressfor the IP address of the network computermaking a request so that all raffic over theInternet appears to be coming from only thepro>ry seryer's IP address.

PS/2-compatible mouse A mouse that plugs intoa round mouse PS/2 port on the motherboard.AIso called motherboard mouse.

public IP address An IP address avaiiable to theInternet.

RAID (redundant array of independent disks)Several methods of configuring multiple hard

drives to store data to increase logical volumesize and improve performance or to ensurethat if one hard drive fails, the data is stillavailable from another hard drive.

RAM (random access memory) Memorymodules on the motherboard containrngmicrochips used to temporariiy hold data andprograms while the CPU processes both.Information in RAM is lost when the PC isturned off.

RAM drive Al area of memory treated as thoughit were a hard drive, but it works much fasterthan a hard drive. The'STindows 9x starrup

G L O S S A R Y I 5 2 7

disk uses a RAM drive. Compare to vtrtualmemory.

RDRAM See Direcr Rambus DRAM.

readlwrite head A sealed, magnetic coil devicethat moves across the surface of a diskreading data from or wriring data to the disk.

ReadyBoost A Vrsta utilit,v rhat uses a flashdrive or secure digital (SD) memory card toboost hard drive performance.

real mode A single-tasking operating modewhereby a program has 1024K of memoryaddresses, has direct access to RAM, and usesa 16-bit data path. Using a memory extender(Himem.sys), a program in real mode canaccess memory above 1024K. Also called15-bi t mode.

Recovery Console A Windows 2000DGcommand-line utility and OS that can be usedto solve problems when Windows can't loadfrom the hard dr ive.

Registry A database that'STindows uses to srorehardware and sofrware configuration informa-tion, user preferences, and setup information.

re-marked chips Chips that have been used andreturned to the factory, marked again, andresold. The surface of the chips might be dullor scratched.

Remote Desktop A Windows tool that gives auser access to his or her Windows desktopfrom an).where on the Internet.

rescue disk A floppy disk that can be used tostart a compurer when the hard drive fails toboot. A/so called ESD (emergency starrupdisk) or startup disk.

resistance The degree to which a device opposesor resists the flow of electricity. As the electri-cal resistance increases, the current decreases.See ohm and resistor.

resistor An electronic device that resists oropposes the flow of electricity. A resistor canbe used to reduce the amount of electricitvc r r n n l i e d t n q n e l r. - * , , . , , 'ctronlc component.

resolution The number of pixels on a monitorscreen that can be addressed by sofrware (forexample, 1024x7 58 pixels).

restore point A snapshot of the Windows Vrsta/XP system stare, usually made beforeinstalling new hardware or applicarions.

RIMM A rype of memory module developed byRambus, Inc.

RJ-11 A phone line connection found onmodems, telephones, and house phone outlets.

RJ-45 connector A connector used with rwisted-pair cable thar connects the cable ro rhe NIC.

ROM (read-only memory) Chips that conrainprogramming code and can't be erased.

ROM BIOS See BIOS (basic input/ourpur system).

root directory The main directory createdwhen a hard drive or disk is first formamed.In Linux, it 's indicated by a forward slash (/).In Windows, it 's indicated by a backwardslash (\) .

rootkit A rype of malicious soffware that loadsitself before the OS boot is complete and canhijack internal \X/indows components so rhatit masks information Windows provides touser-mode utiiities such as Windows Exnloreror Task Manager.

routable protocol A protocol that can be routedto interconnected nerworks on the basis of anetwork address. TCP/IP is a routableprotocol, but NeIBEUI is not.

sags See brownours.

SAIA (serial AIA) An ATAPI cabling methodthat uses a narrower and more reliable cablethan the 8O-conductor cable. See also PATA(parallel ATA).

SCSI (Small Computer System Interface) A fastinterface berween a host adapter and the CPUthat can daisy-chain as many as 7 or 15devices on a single bus.

SCSI ID A number from 0 to 15 assigned to eachSCSI device attached to the daisy chain.

SDRAM (synchronous DRAM) A ryp. of memorystored on DIMMs that runs in slnc withthe system clock, at the same speed as themotherboard.

SDRAM tr See DDR SDRAM (Doubie Data RareSDR-AM).

G L O S S A R Y

secondary storage Storage that's remote to theCPU and permanently holds data, even whenthe PC is turned off, for example, a hard drive.

sector On a disk surface, it's one segment of atrack, which almost always contains 512 bytesof data.

sequential access A method of data access usedby tape drives, whereby data is written orread sequentially from the beginning to theend of the tape or until the data is found.

serial ATA cable An IDE cable that's narrowerand has fewer pins than the parallel iDE 80-conductor cable.

serial mouse A mouse that uses a serial port andhas a female 9-pin DB-9 connector.

serial port A male 9-pin or 25-pin port on acomputer system used by slower VO devices,such as a mouse or modem. Data travelsserially, one bit at a time, through the port.Serial ports are sometimes configured asCOM1, COM2, COM3, or COM4.

service pack See patch.

Service Set Identffier (SSID) The name of theaccess point for a wireless nerwork.

SFC (System File Checker) A Windows toolthat checks to make sure Windows is usingthe correct versions of system files.

shadow RAM or shadowing ROM ROMprogramming code copied into RAM to speedup the system operation because of the fasteraccess speed of RAM.

shortcut An icon on the desktop that points to aprogram that can be run or to a file or folder.

SIMM (single inline memory module) A mrniaturecircuit board used in older computers to hoidRAM. SIMMs hold 8. 1'6.32. or 64 MB on asingie module.

simple volume A type of dynamic volume usedon a singie hard drive that corresponds to aprimary partition on a basic disk.

single-voltage CPU A CPU that requires onevoltage for both internal and UO operations.

slack Wasted space on a hard drive causedby not using all available space at the endof clusters.

sleep mode A mode used in many "green"systems that allows them to be configuredthrough CMOS to suspend the monitor oreven the drive, if the keyboard and/or CPUhave been inactive for a set number ofminutes. See also Green Standards.

slimline case See compact case.

snap-ins Components added to a console byusing the Microsoft Management Console.

SO-DIMM (small outline DIM ,t) A type ofmemory module used in notebook computersthat uses DIMM technology and can have72 pins or 144 pins.

soft boot To restart a PC without turning offthe power, for example, in Windows XP, byclicking Start, Turn Off Computer, Restart.Also called warm boot.

soft power See soft switch.

soft switch A feature on an ATX systemthat allows an OS to power down thesystem and ailows for activiry such as akeystroke or nefwork activity, to power upthe system. Also called soft power.

soffware Computer programs, or instructionsto perform a specific task. Software can beBIOS, OSs, or application software, such as aword-processing or spreadsheet program.

software cache Cache controlled by sofrware,whereby the cache is stored in RAM.

solid state device (SSD) A storage device thatuses memory chips to store data instead ofspinning disks.

SO-RIMM (small outline RIMM) A 150-pinmemory moduie in notebooks that usesRambus technology.

spacers See standoffs.

SPGA (staggered pin grid array) A feature of aCPU socket whereby the pins are staggeredover the socket to squeeze more pins into asmall space.

SPI (SCSI Parallel Interface) The part of theSCSI-3 standard that specifies how SCSIdevices are connected.

spooling Placing print jobs in a print queue sothat an application can be released from the

G L o S S A R Y I 529

printing process before printing is completed."Spooling" is an acronym for "simultaneousperipheral operations online. "

SRAM (static RAM) RAM chips that retaininformation without the need for refreshing,as long as the computer's power is on. Theyare more expensive than traditional DRAM.

standby time The time before a "green" systemreduces 92 percent of its activity. See alsoGreen Standards.

standoffs Round plastic or metal pegs thatseparate the motherboard from the case so thatcomponents on the back of the motherboarddon't touch the case. Also called spacers.

startup BIOS The part of system BIOS respon-sible for controlling the PC when it's firstturned on. Startup BIOS gives control over tothe OS after it 's loaded.

startup disk See rescue disk.

startup password See power-on password.

static electricity See ESD (electrostatic discharge).

static IP address An IP address permanentlyassigned to a workstation.

stop error An error severe enough to cause theoperating system to stop all processes. Seealso blue screen.

STP (shielded rwisted-pair) cable A cable madeof one or more rwisted pairs of wires andsurrounded by a metal shield.

streaming audio Downloading audio data fromthe Internet in a continuous stream of datawithout downloading an entire audio file first.

subdirectory A directory or folder contained inanother dfuectory or folder. Also called chrlddirectory or folder.

subnet mask A group of four numbers (dotteddecimal numbers) that tell TCP/IP whether aremote computer is on the same or a differentnetwork.

surge suppressor or surge protector A deviceor power strip designed to protect electronicequipment from power surges and spikes.

suspend time The time before a "Green" systemreduces 99 percent of its activiry. Afrer this dme,

the system needs a warm-up time so that theCPU, monitor, and hard drive can reach fullactivify.

swap file A file on the hard drive used by theOS for virtual memory. Also called page file.

synchronous SRAM SRAM that's faster and moreexpensive than asynchronous SRAM. It requiresa clock signai to validate its control signals,enabling the cache to run in step with the CPU.

Sysedit The Windows System ConfiguratronEditor, a text editor generally used to editsystem files.

system BIOS BIOS located on the motherboard.

system board See motherboard.

system bus The bus befween the CPU andmemory on the motherboard. The busfrequency in documentation is called thesystem speed, such as 400 MHz. Also calledmemory bus, motherboard bus, front-sidebus, local bus, or host bus.

system clock A line on a bus dedicated totiming the activities of components connecredto it. The system clock provides a continuouspulse that other devices use to time themselves.

system disk 'Windows

terminology for abootabie disk.

system partition The active partition of thehard drive containing the boot record and thespecific fiIes required to load Windows.

system resource A channel, iine, or address onthe motherboard that can be used by the CPUor a device for communication. The four sys-tem resources are IRQ, VO address, DMAchannel, and memory address.

System Restore A \Tindows utiiiry, similar to theScanReg tool in earlier versions of Windows,used to restore the system to a restore point.Unlike ScanReg, System Restore can't be runfrom a command prompt.

system state data In Windows 2000DG, filesthat are necessary for a successful load of theoperating system.

System.ini A text configuration file used by'Windows

3.x and supported by Windows 9xfor backward comoatibiliw.

530 I G L 0 S S A R Y

TAPI (Telephony Application ProgrammingInterface) A standard developed by Inteland Microsoft that can be used by 32-bttWindows communication programs forcommunicating over phone lines.

Task Manager (Taskmgr.exe) A'Sfindows utilirythat lets you view the applications andprocesses running on your computer as well asinformation about process and memory per-formance, nerwork activity, and user activity.

TCP/IP (Transmission Control Protocol{nternetProtocol) The suite of protocols thatsupports communication on the Internet. TCPis responsible for error checking, and IP isresponsibie for routing.

telephony A term describing the technology ofconverting sound to signals that can travelover telephone lines.

terminating resistor The resistor added at theend of a SCSI chain to dampen the voltage atthe end of the chain.

termination A process necessary to prevent anecho effect of power at the end of a SCSIchain, resulting in interference with the datatransmission.

thermal compound A creamlike substance thatis placed berween the bottom of the coolerheatsink and the top of the processor toeliminate air pockets and help to draw heat offthe processor.

TIFF (Tagged Image File Format) A bitmappedfile format used to hold photographs,graphics, and screen captures. TIFF files canbe rather large and have a .tif fi ie extension.

top-level domain The highest level of domainnames) indicated by a suffix that tells some-thing about the host. For example, .comis for commercial use and .edu is for educa-tional institutions.

tower case The largest type of personalcomputer case. Tower cases stand verticallyand can be as tall as two feet. They havemore drive bays and are a good choice forcomputer users who anticipate making majorupgrades.

trace A wire on a circuit board that connectstwo components or devices.

track One of many concentric circles on thesurface of a hard drive or floppy disk.

translation A technique used by system BIOSand hard drive controiler BIOS to break the504 MB hard drive barrier, whereby a differentset of drive parameters are communicated tothe OS and other sofrware than that used bythe hard drive controller BIOS.

UART (universal asynchronous receiver-transmitter)chip A chip that controis serial ports. Itsets protocol and converts parallel databits received from the system bus intoserial bits.

UDF (Universal Disk Format) file system A filesystem for optical media used by all DVDsand some CD-Rs and CD-R!7s.

unaftended installation A'STindows installattondone by storing the answers to rnstaliationquestions in a text file or script that Vindowscalls an answer file. Vith this instaliation r.vpe,answers don't have to be typed in during theinstallation.

upgrade install The installation of an OS on ahard drive that already has an OS installed in

such a way that settings kept by the old OSare carried forward into the upgrade, includinginformation about hardware, sofrware, anduser preferences.

URL (Uniform Resource Locator) An addressfor a resource on the Internet. A URL cancontain the protocol used by the resource' thename of the computer and its network, andthe path and name of a file on the computer.

USB (universal serial bus) port A type of port

designed to make installation and configura-tion of VO devices easy, providing room foras many as 1,27 devices daisy-chainedtogether.

USB host controller Manages the USB bus. Ifthe motherboard contains on-board USBports, the USB host controller is part of thechipset. The USB uses oniy a single set ofresources for all devices on the bus.

user account The information, stored in theSAM database, that defines a Windows2000D(P user, including user name' password,memberships, and rights.

G L o S S A R Y I 5 3 1

user profile A personal profile about a user thatenabies the user's desktop settings and otheroperating parameters to be retained from onesession to another.

USMT (User State Migration Tool) A'WindowsVistaD(P utiliry that helps you migrate userfiles and preferences from one computer toanother to help users make a smooth transi-tion from one computer to another.

UTP (unshielded twisted-pair) cable A cablemade of one or more fwisted pairs of wrresthat is not surrounded by a metal shield.

V (volt) A measure of potential difference in aneiectrical circuit. A computer ATX powersupply usually provides five separate voltages:+ 1 2 V , - 1 2 V , + 5 V - 5 V , a n d + 3 . 3 V .

value data In lTindows, the name and value ofa setting in the Registry.

VCACI{E A built-in Windows 9x32-bir sofrwarecache that doesn't take up conventional mem-ory space or upper memory space, asSMARTDTive did.

video card An interface card installed in thecomputer to control visual output on a moni-tor. Also called display adapter.

virtual device driver (VxD or VDD) A Vindowsdevice driver that can have direct access to adevice. It might depend on a Windows com-ponent to communicate with the device itself.

virtual memory A method whereby the OS usesthe hard drive as though it were RAM.Compare /o RAM drive.

virtual real mode An operating mode that workssimilarly to real mode provided by a 32-bitOS for a 15-bit program to work.

virus A program that often has an incubationperiod, can infect other computers, and isintended to cause damage. A virus programmight destroy data and programs or damage adisk drive's boot sector.

virus signature A set of distinguishing character-istics of a virus used by antivirus sofrware toident i fy the virus.

volatile Refers to a kind of RAM that's temporarycan't hold data very long, and must be refreshedfreauentlv.

voltage Electrical differential that causes currentto flow, measured in volts. See also V (volt).

voltmeter A device for measuring electrical ACor DC voltage.

volume See Iogical drive.

\fRAM (video RAM) RAM on video cards thatholds the data being passed from the com-puter to the monitor and can be accessed byrwo devices simulfaneousiy. Higher resolu-tions often require more video memory.

\rRM (voltage regulator module) A deviceembedded or installed on the motherboardthat regulates voltage to the processor.

VxD See virtual device driver.

W (watt) The unit used to measure power.A typical computer can use a power supplythat provides 400W.

wait state A clock tick in which nothinghappens, used to ensure that the micro-processor isn't getting ahead of slowercomponents. A 0-wait state is preferable to a1-wait state. Too manv wait states can slowdown a system.

WAN (wide area network) A network orgroup of nerworks that span a largegeographical area.

warm boot See soft boot.

wattage Electrical power measured in watts.

WTP (Windows File Protection) A'Windows2000D0 tool that protects system files frommodification.

Wi-Fi See IEEE 802.11b.

wildcard A *' or ? character used in a commandline that represents a character or group ofcharacrers in a f i lename or extension.

Vin.ini The'STindows initialization file thatcontains program configuration informationneeded for running the lTindows operatingenvironment. Its functions were replaced bythe Registry beginning with'$Tindows 9x,which stil l supports it for backward compari-bility with Windows 3.x.

Win386.swp The name of the Windows 9xswap file. Its default location is C:\'STindows.

532 I c lossrnv

WLAN (wireless LAN) A rype of LAN thatdoesn't use wires or cables to create connec-tions; instead, it transmits data over radio orinfrared waves.

workgroup In'$7indows, a logical group ofcomputers and users in which administration,resources, and security are distributedthroughout the nerwork, without centralizedmanagement or securiry.

worm An infestation designed to copy itselfrepeatedly to memory, on drive space or on anetwork, until little memory or disk spaceremain.

WRAM (window RAM) Dual-portedvideo RAM that's faster and less expensivethan VRAM. It has its own internal buson the chip with a 256-bi t-widedata path.

ZIF (zero insertion force) socket A socketthat uses a small iever to apply even forcewhen you install the microchip into thesocket.

zone bit recording A method of storing dataon a hard drive whereby the drive can havemore sectors per track near the outside ofthe platter.