Computer Industry Glossary

8.3 naming convention: a file naming scheme used by earlier file systems that permitted file names of up to eight characters, plus an extension of up to three characters.

Active Desktop: A method of configuring the Windows desktop to behave as if it were a web page, allowing single-click activation of icons and other web-like features.

Address Bus: A bank of wires running throughout the system and into the CPU that specifies specific locations. The total addressable space is calculated as 2^x, where X represents the total number of wires in the bus.

Allocation Scan: A BIOS routine that reassigns resources to Plug ‘n Play devices installed on a computer system.

Alpha Channel: Eight bits used by 32-bit TrueColor to apply effects such as translucency and fogging.

Alternating Current: An electrical current that reverses the direction of current flow many times each second.

Anti-aliasing: A process through which textures in an image are redrawn to more accurately reflect perceived distance.

Appendix C

Areal Density: The total amount of storage capacity for a specific unit of area on the surface of the drive platter.

Arithmetic Logic Unit: A subcomponent of a microprocessor responsible for executing simple mathematical calculations, such as add, subtract, multiply and divide. It cannot perform floating point calculations.

Asynchronous Timing: A device on a bus can deliver its data at any speed it sees fit to a reserved area of memory called a buffer. Data is then fed to the CPU at a rate optimal to the CPU.

Attribute: A property assigned to a file or directory on the system that defines certain characteristics of that file.

Average Access Time: The amount of time required by a disk drive to lock on to the first sector that contains data requested by the controller.

Average Seek Time: The amount of time it takes to locate and lock on to the first track that contains data requested by the controller.

Back Side Bus: A portion of the EDB. It is the path that data takes as it moves from cache loaded on the CPU’s die into the CPU’s registers.

Basic Disk: A disk that has been configured to conform to the legacy partition-oriented approach to file systems.

Battery Memory: A phenomenon exhibited by rechargeable batteries by which the pattern of recent charge cycles affects the maximum charge the battery will accept.

Baud Rate: The electronic frequency over which data is transmitted.

B-channel: A carrier channel used by ISDN for transmitting user data at 64KB/s. Multiple B-channels can be combined for higher transmission rates.

Beaconing: A process that occurs on a token ring network in which each station on the network sends a signal to its upstream neighbor and its downstream neighbor asking if it’s seen the token lately.

Benchmarking: A method of measuring the base performance of a device or system before any load is placed on it.

Bezel: The plastic frame that masks off the unusable part of a monitor’s image.

Binary: A Base2 counting system that consists of the two characters 0 and 1.

BIOS Extension: A string of code that interfaces the operating system to the BIOS interrupts.

Bit Cell: The collection of magnetized particles that comprise a single bit on magnetic media.

Bit: A single zero or one, resulting in a single transition between off and on.

Blackout: A complete loss of power to an entire area.

Block Mode: The data transfer setting that allows multiple commands to be moved over an interface on a single interrupt cycle.

Block Transfer: The movement of multiple commands over an interface on a single interrupt cycle.

Block: The number of sectors on a hard drive that UFS uses as the smallest recognizable data unit.

Boot Block: A feature present on most modern system boards that allows the system to boot to a minimal configuration, including floppy drive support, in the event that the BIOS is corrupted or destroyed by a virus.

Bootstrap Loader: A program that reside on the BIOS chip that is responsible for locating and initializing the Master Boot Record.

Bounded Media: Any medium that physically connects a device to the network by way of a tangible cable.

Branch Prediction: The ability of certain CPUs to be able to predict a situation where either one of two separate subroutines may be run, depending on the results of processing code not yet completed. A CPU capable of branch prediction will load a few lines of code from each subroutine.

Break Code: A signal generated by a keyswitch with the key is released.

Bridge: A device that interconnects two networks or segments of a network of different topologies or different platforms together. Also, A specialized circuit that moves data between two disparate devices or busses in a such a manner that both devices become compatible.

Brownout: A drop in voltages that lasts a noticeable period of time.

Bubblejet printer: Another term for a thermal printer.

Burn-in: The tendency for a CRT monitor to permanently etch an image onto the inner surface of the tube if the image stays of the screen for too long a period.

Burst Mode: The speed at which data moves from the R/W heads to a drive’s buffer memory. Also known as Internal Host Rate.

Bus Mastering: A technology that allows two compatible devices to exchange data directly without require arbitration or processing of that data by the CPU.

Byte Mode: Like nibble mode, it provides bi-directional communication between the printer and the computer. Unlike nibble mode, it sends eight bits on each cycle. Speeds is byte mode are comparable to those of compatibility mode.

Byte: Any combination of eight zero’s or ones.

Cabinet File: A compressed file that holds a large number of smaller files that can be uncompressed and installed as needed.

Caddy: On a CD-ROM (or similar) drive, it is a form of loading mechanism that consists of a plastic CD holder encases the CD while it is in the drive.

Capacitor: An electrical component that stores electrical current and provides it to the circuit as needed.

Capacity: The total number of bits a memory chip holds.

Card Services: The portion of a PC card driver that interprets the command set for a specific device.

CAS Latency: The delay that occurs between RAS and CAS. Also known as RAS/CAS delay.

Cascade: A process by which multiple circuits are linked together in such a way as they appear to the system as a single device.

Cathode: A negatively charge device that emits a stream of electrons when heated.

Central Arbitration Point: A circuit that offloads the responsibility for refereeing and processing the transfer of data between two bus-mastering devices.

Channel: A dedicated path for data to take that prevents other data from competing for time on the bus.

Character Set: The code used to generate printable symbols that human users can understand.

Checksum: An error detection/correction mechanism that works by counting the number of 1s present in the payload and storing that value in the BCC block of the packet.

Chip Timing: The total combination of clock cycles required for a memory I/O operation, including the leadoff timing numbers and the DRAM Read Timing numbers.

Chipset: A matched set of two (three on some of the older systems) Ics that control critical system functions, including bus speeds, memory types and capacity, and the type of hardware supported by a motherboard.

Chop: A 16-bit piece of data generated when music is sample once during the digital recording procedure.

Clean Install: The fresh installation of an OS over a newly partitioned and formatted hard disk.

Client: Any device or software that requires the services of another device or piece of software in order to perform its function.

Clock Cycle: A timing signal generated by an electrical current that synchronizes data movement throughout the system. As an electrical current, a clock cycle resembles a sine wave with a rising half of the signal and a falling half.

Closed-ended question: A question that leads to an answer that provides no further insight or leads to an abrupt dead end to the discussion.

Cluster: Another term for the file allocation unit (FAU)

Cluster: The minimum number of sectors a specific file system can recognize as a single data unit. Another term for FAU.

CMOS Setup: One of the programs loaded on the BIOS chip. This particular program allows user-defined parameters relating to BIOS settings to be configured.

Coaxial: A cable over which the signal and ground both follow the same axis.

Codec: A coined term derived from two other terms, coder and decoder. A Codec is an IC that has been programmed to covert data from one form to another. An example of this would be a chip that takes analog signals and converts them to digital, and vice versa.

Coil: And electrical component consisting of tightly wound wire that is used to filter out AC current and low frequency signals.

Cold Fusing: A process used by some phase change printers that uses pressure rollers to press the ink into the paper.

Color Depth: The number of individual hues that can be generated by a given display setting.

COM Port: A predefined combination of an IRQ and an I/O Address configured for communications devices.

Command Overhead: The number of instructions that must be executed in order to carry out a specific request, combined with the speed at which the device can carry out those instructions.

Command Overlapping: The ability of a device to start processing a command even before the command issued prior to it has completed its cycle.

Command Queuing: Allows a device to store a series of commands in a buffer area, assuring that as one command is completed another one is rolled up to the gate and ready to go.

Compatibility Mode: A unidirectional signal that is used to send data to the printer. This is also known as Centronix Mode. Very slow, at approximately 150KB/sec.

Computer: Any device that can accept the input of user data, process that data according to a specific set of instructions and the provide the results of that processing in the form of output to the end user.

Conductor: Any substance that encourages the flow of electricity. Also the man at the podium that waves a white stick in front of the musicians.

Container: A collection of objects on the system or network that have been gathered together into a single administrative unit.

Continuity Module: A null memory module that fills the empty banks on a system using Rambus memory.

Control Set: A collection of registry settings that defines the system configuration for Windows during the boot process.

Conventional Memory: The first 640K of any computer system. In the old days of DOS, the only place where programs could run was in conventional memory.

Conventional memory: the first megabyte of RAM, divided into 640K for running programs and 384K reserved for system use.

Convergence: The accuracy to which multiple beams of electrons or light can focus on the same point.

Cool: A shift in the color of an image toward the blue side.

Cooperative multitasking: The ability of an OS to simultaneously run more than one program at once, placing responsibility on the application for relinquishing control of the system.

Co-processed: Any adapter or device that is equipped with a microprocessor that offloads some of the work of the PC’s CPU is said to be co-processed.

Crash dump: A direct copy of the entire contents of system RAM copied to a file on the hard disk.

Credentials: Information provided by the user, including, but not restricted to the User ID and password, that grants that user access to a system or network.

Credentials: On a network, these consist of the user ID and password that provides network access for the user.

Cross-linked File: FAUs that originated as totally different files, but now think that they are the same.

Crossover Cable: A network patch cord that routes the transmit signal from one device to the receive terminals on the other device.

Current: The number of electrons that flow through a circuit in a fixed amount of time.

Cyanine Dye: A bluish colored dye that was used in the recording layer of early generations of CDR media.

Cycle Rate: The amount of time it takes for a specific device under the control of a timing mechanism to complete one “tick” of that timer.

Cylinder: A virtual structure created by a track and all those on each surface of the other platters that line up to it.

Data Cache: A set of registers used for storing data loaded by the prefetch until such time as the CPU is ready to use it.

Data Encoding Mechanism: The method used by a device to convert digital information into an electronic format recognizable by the target device.

Data Phase: The portion of an I/O operation that performs the actual transfer of data from device to device.

Datacom: A term coined to describe any equipment used in data communications.

D-channel: A 16KB/s or 64KB/s channel used by ISDN for control data, including synchronization, acks and nacks and other non-user data.

Decimal: A Base10 counting system that consists of ten characters, 0 through 9.

Decode Unit: The subcomponent of a microprocessor that takes complex instructions and breaks them down into a series of simpler instructions that the CPU is able to understand.

Default Gateway: The route through which all packets that contain addresses that the transmitting device cannot resolve will be sent.

Deflection yoke: A circular array of powerful magnets that act to deflect a beam of electrons from it’s natural path.

Depth Queuing: A mathematical algorithm that recalculates the hue and intensity of colors in respect to increasing distances.

Device ID: A unique number assigned to each device on a SCSI chain, including the host adapter, that identifies it to other devices on the chain.

Die: The wafer of silicon used to stamp out a sheet of CPUs. It’s also what that very CPU will do later if it tries to divide by zero.

Dielectric Layer: A transparent layer of material above and below the recording layer of a CD-RW that dissipates the heat built up in the CD during the recording process. Voice: A collection of preprogrammed harmonics that are used to simulate the sound made by a particular instrument.

Differential Signaling: A method by which a single data wire on a parallel cable is matched up by a wire carrying the inverse of the signal being carried by the data wire.

Digital Grain: A coarseness of a digitized image resulting from the enlargement of that image without adjusting for resolution.

Digital Noise: Unwanted color artifacts introduced into a digitized image during capture and/or by imaging software during the processing of that image.

Digital Signature: an encrypted piece of data added to a file to guarantee its authenticity.

Diode: An electrical component that freely permits the flow of electrons in one directions, but resists electron flow in the opposite direction.

Direct Current: An electrical current that exhibits a steady directional flow from a source of relative positive voltage to a target of relative negative voltage.

Directory Attribute: A single bit that identifies an entry in the Directory table as being a subdirectory rather than a file.

Directory Table: A database of all file names on a hard drive and the partitions to which they are associated. Other information pertaining to file system security is also contained here.

Directory: a container node of a file system that can contain other directories or files.

Disk Duplexing: Exactly duplicating the data on a system on two different drives, each hanging off of a separate controller.

Disk Duplexing: The duplication of data on two different hard drives hanging off of different controllers.

Disk Editor: A piece of specialized software that allows a user to examine and alter the contents of a disk drive bit by bit. Disk editors even allow access to parts of the drive not normally accessible by the user, such as FAT.

Disk Mirroring: Exactly duplicating the data on a system on two different drives hanging off of a single controller.

Disk Mirroring: The duplication of data on two different hard drives hanging off of the same controller.

Disk slack: the amount of disk storage that is wasted by null files and/or small files stored on the hard disk.

Diskette: A term typically applied to the 3.5” floppy disk in order to distinguish it from the 5.25” floppy disk.

Distribution Server: A centralized storage location for the installation files of operating systems or applications.

Dithering: A process of blending colors of adjacent areas in an image to make the appearance more natural.

Docking Station: A device to which a laptop computer can be attached that provides additional hardware support, including I/O ports, PCI slots and drive bays.

Domain Divider Switch: A device that allows external SCSI devices to be shared by multiple host computers.

Domain Validation: A process by which a SCSI host adapter sends out a series of commands to each device on the chain and calculates each devices maximum data transfer rate.

Domain: A collection of all resources and users that fall under the control of a single administrative unit. In the case of Windows NT, the administrative unit would be the PDC.

Dot-pitch: The distance separating two like-colored phosphors that are adjacent to one another.

Double Buffering: The use of two separate buffers, so that as a frame is displayed on the monitor, another frame is the queue, ready for display, while yet a third is being assembled by the graphics adapter.

Double-transition clocking: The movement of two transfers of data on a single clock cycle.

DRAM Read Timing: The number of clock cycles required during a memory I/O operation for each transfer of data from RAM to cache, along with how many of these transfers can take place before the memory must refresh.

Drive Bay: A metal frame within a computer enclosure (that may or may not be removable) that supports disk drives.

Drive Rails: Devices that attach to the side of a disk drive that allows the user to install or subsequently remove it without needing any tools.

Drive Translation: A technique by which an address space beyond what Int13h can read is converted into something that it can understand.

Dual-ported: Any device that has separated input and output paths, allowing new data to be moving onto the devices on the same clock cycle that processed data is being moved off.

Duplex: A communications method by which a device can be transmitting and receiving at the same time.

Dynamic disk: A disk that has been configured for a file system based on volumes rather than partitions.

Edge Triggered: Any response that elicited and/or controlled by a direct electrical signal coming from a pin or wire on a device. The voltage is applied and the device depends on the interrupt controller to “remember” that it sent the signal.

Electron gun: A cathode that, when heated, emits a stream of electrons from the positive pole.

Ending delimiter: A single bit at the end of a byte of data being transmitted asynchronously that marks the end of a byte.

Enhanced I/O Controller Hug: The IC in the newer Intel chipsets that manages all function other than memory and AGP.

Erase Power: A medium power setting for the optical stylus of a CD-RW, which it uses to melt the crystals generated by the previous recording session back into the uncrystallized recording layer.

Executable Marker: A pointer in the MBR that directs the boot sequence to the first line of code for the primary kernel file of the OS installed.

Executive services: The layer of the operating system responsible for running commands.

Expanded memory: Memory beyond conventional memory that is under the direct management of a paging frame and a expanded memory manager.

Expanded Memory: Memory beyond the first megabyte of RAM that can be used for storing data. Expanded memory could not be used for executing programs.

Expansion Bus: A circuit on a motherboard that allows accessory devices to be added to the system. The expansion bus straddles several of the primary system busses.

Extended memory: all memory installed on a system above the 1MB of conventional memory.

Extended Memory: Memory beyond the first megabyte of RAM that can be used for data storage and the execution of program code.

External Data Bus: The wires that move data from outside the CPU to the internal registers of the CPU.

External Host Rate: How fast data moves from a drive’s controller to RAM.

Farad: The major measurement of a capacitor’s ability to store energy.

Fast SCSI: SCSI over a 10Mhz bus.

Fatal Exception: Any event that stops the CPU completely. These can include programming errors, such as a request to divide any number by zero, or a hardware event that returns a non-maskable interrupt.

Faux parity: A null chip that fooled a system into thinking parity memory was installed, when in fact, it was not.

File System: The mechanism used by a hard drive to map the specific sectors used by any given file.

File: a collection of data that is intended to stay together.

Firewall: A hardware or software barrier that allows access to external networks for users inside the firewall, but denies access from the outside.

Firewire: A high-speed serial SCSI connection originally developed by Apple Computer Corporation that is capable of 400Mb/s throughput.

Floating Height: The distance above a hard drive’s platter that the R/W heads hover as the platter spins beneath.

Floating Point Unit: A subcomponent of a microprocessor that is responsible for more complext mathematical calculations.

Flux Reversal: A transition of magnet charge from a positive to a negative state, or vice versal.

Fogging: A technique of implying distance in an image by making objects that are farther away less distinct.

Font: The size and characteristic (such as bold or italic) of a particular typeface.

Form Factor: A preconfigured size, orientation and design layout for a particular component used in order to assure compatibility between manufacturers.

Form factor: Preset design specifications regarding size, orientation of components and screw positions that allows different manufacturers’ motherboards to fit into other manufacturers’ enclosures.

Frame Buffer: Dedicated memory used by a graphics adapter to build the next image frame to be displayed in the time that the current image frame is on the screen.

Frame: The metal skeleton that provides the primary support for a computer enclosure.

Front Side Bus: A portion of the EDB. It is the path that data takes from outside locations to make its way into the CPU.

Full height: A term that describes a disk drive that is 3½” from top to bottom.

Fuse: An electrical component that consists of a filament that vaporizes when a certain amount of current tries to pass.

Gamma: A mathematical calculation of the perceived density of an image, in terms lightness or darkness.

Gauge: A measurement of the thickness of a substance such as sheet metal or wire. Larger numbers indicate smaller sizes.

Glossary of Terms

Half height: A term that describes a disk drive that is 1.62” from top to bottom.

Half-duplex: A communications method by which a device can either transmitting or receiving, but not both at the same time.

Hard Fault: A situation in which data sought by the CPU was neither in memory, nor in the paging file. As a result a new hard disk search must be initiated.

Harmonics: Sound frequencies above the root frequency that are generated by an instrument or voice when a certain note is generated.

Head Crash: A disastrous event caused by the R/W head in a drive coming into physical contact with the platter while it is spinning.

Head Parking: A process of positioning R/W heads in a hard drive in a place where contact with the platter will do no harm.

Helical Scan: A recording technology that places data in diagonal tracks along the tape, as opposed to a linear track that follows parallel to the tape edge.

Hexadecimal: A counting system that uses Base16 as it root. As such, this system requires a total of 16 different characters to represent base values.

High Memory: The first 64K of memory beyond the 1MB of conventional memory, usually used as a paging file for access into extended memory.

Host Controller: The adapter installed on a system or embedded in the motherboard that manages SCSI devices.

Hot-pluggable: Another term for hot-swappable. A hot-pluggable device can be added or removed to its bus without the necessity of bringing the computer down.

Hot-swap: The ability to replace or remove a device from a computer system without having to shut the system down.

Hub: A device that interconnects multiple hosts on a star network over a single segment.

Hyperthreading: The ability of certain CPUs to execute multiple lines of code at the same time.

Hypothesis: Any theory that can be tested to be proven either true or false. Post Card: A devices that follows each step of the POST procedure and reports the results. Should the POST fail, the last successful process will be indicated in an encoded display.

I/O Address: A location in memory that identifies where data from a specific device will be stored as it moves from either the application or the CPU to the device, or vice versa.

i386 instruction set: The basic CPU-level instructions embedded in the 80386 microprocessor. These instruction went on to become the core instructions for subsequent generations of Intel-compatible microprocessors.

Icon: A small picture linked to an application shortcut

Index Hole: A small opening in the covering of a floppy disk that allows the R/W heads to properly align to Track 0, Sector 1.

Initialization String: A series of AT commands that are issued by the originate modem during the connection process.

Initiator: The device in a bus-mastering chain that is to act as the source of the data being transferred.

Input: Any data that is intended and/or ready to be sent to the CPU for processing.

Instruction Cache: A set of registers used for storing instruction code loaded by the prefetch until such time as the CPU is ready to use it.

Instruction Pipelining: The ability of certain CPUs to be loading the next set of instructions or data at the same time it processes the current set.

Insulator: Any substance that tends to resist the flow of electricity.

Int13h Extensions: Additional instructions added to the BIOS that intercept hard disk I/O operations and provide the drive translation required by hard disks larger than 8GB.

Interleave Ratio: The number of sectors that must pass beneath the R/W heads between the reading of one sector and the time the heads will be ready to read the next sector. For example, on a 3:1 ration, the heads will read or write on sector, two sectors will pass by completely ignored, then the next sector will be written. The unused sectors will be filled in during the next two rotations of the platter.

Internal Host Rate: The speed at which data moves from the R/W heads to a drive’s buffer memory. Also known as Burst Mode.

Interpolated Resolution: The generation of dot patterns by an imaging device that were not physically read by the devices imaging circuits.

Interrupt Request: A electrical signal generated by either a device in the system or the CPU that alerts the opposite end that it has data to transmit.

Interrupt: On a software level, it is a string of code that is called in order to perform a specific function. The BIOS uses software interrupts to manage hardware. On a hardware level, it is an electrical signal that notifies the CPU that a device needs to open communications (or vice versa).

Inverter: A device or circuit that converts DC current to AC current.

Journaling: A process used by certain OSs and applications, by which any changes made to the basic infrastructure or code are recorded in a log prior to being enforced.

Kernel Mode: An operational mode for an OS that manages system functions.

Key Matrix: The specific geometric layout of they keyswitches on a keyboard.

Key: A null space on an edge card connector or memory module that is used for properly aligning the device into its slot.

Keycap travel: The actual distance a user must press a key on a keyboard in order to produce results.

Keycap: The plastic button the user presses down when typing on a keyboard.

Keyswitch: The electro-mechanical connection that informs the keyboard controller circuitry that a key has been pressed.

Land: All of the reflective surface of the recording layer in optical media that has not been burned or punched into a pit.

Landing Zone: An area on the hard disk’s platter where the R/W heads can be safely parked.

Latency: The delay that occurs from the time the CPU makes a request for data and the time that information can be accessed from the device holding the data. All devices, including memory and hard drives, exhibit latency.

Lazy writing: A a disk-caching scheme that allows the OS to perform write operations to a disk at a time when the controller and disk aren’t involved with read operations.

Leadoff Timing: The number of clock cycles required to locate and lock on to the first bit of data requested in an I/O operation once the MCC receives the request.

Level Triggered: A response that is arbitrated by a control circuit and/or device driver that allows the same device to make use of one of several interrupt channels. The level triggered interrupt, raises the voltage on the appropriate wire and holds it until the expected response is received.

Library: In programming, a collection of subroutines that are required by several or all applications running on a computer. By storing this code in a single file, it does not need to be duplicated many times over.

Line Conditioner: A device that is able to filter out transient noise, such as EMI, from the current.

Linewidth: The actual thickness of traces used within the CPU.

Load Point: The physical location on a tape where data begins to be stored.

Local loop carrier: A communications service provider. They provide the electronic link between geographically separated devices.

Logic Gate: Two or more transistors whose position will direct the positioning of the next bank of transistors downstream.

Logical Drive: A section of disk space isolated from the rest of the same physical disk that appears to the user as a separate disk drive.

Loopback adapter: A piece of hardware that routes an output signal directly back to the computer, giving the impression that a device was present.

Lost Cluster: See Lost File Fragment

Lost File Fragment: FAU on the hard drive that contains data, but that has lost the pointers that identify the file to which it belongs.

LPT Port: A predefined combination of an IRQ and an I/O Address configured for line printers.

Make Code: A signal generated by a keyswitch when the key is first pressed down.

Media: The substance or energy wave over which a data signal is transmitted.

Megabyte: Depending on whether you are calculating a value in binary or decimal, a megabyte is either 1,000,000 bytes (decimal) or 1,048,576 bytes (binary). A binary megabyte is used in virtually every circumstance except when calculating hard drive capacity. Hard drive manufacturers typically define capacity in decimal values.

Memory Bank: The total number of memory modules required to assure that the bit width of available memory matches the bit width of the CPU in use.

Memory Controller Hub: The IC in the newer Intel chipsets that manages RAM and AGP bus.

Memory pool: The total address space available to an OS and the applications running on top of it.

Message block: A piece of data being transmitted by a modem that represents a portion of the overall data being sent.

Metafile: A related string of streaming data that contains the information that is used to implement the file system structure. Also, a metafile is a structured graphical file, also containing streaming data.

Microfarad: The minor measurement of a capacitor’s ability to store energy.

Mini-connector: A smaller four-pin connector coming off a power supply that delivers current to devices such as floppy disk drives.

Mirrored Volume: A single logical drive that is made of two disks, both of which contain identical data.

Modem: Modulator/demodulator. A device that converts parallel digital signals into serial analog signals for transmission over a wire.

Molex: The larger four-pin connector coming off a power supply that delivers current to devices such as CD-ROM drives or hard drives. Technically speaking, it is the name of the company that invented the plug.

Multi-mode fiber: A fiber optics strand that moves multiple signals through the core.

Multisession: The ability to record data onto a CDR or CD-RW in several stages, without closing out the TOC.

Multitasking: The ability of an OS to simultaneously run more than one program at once.

Native Capacity: How much data any given medium can store without benefit of compression. Various compression techniques all data beyond native capacity to be recorded.

Native File Encryption: A technology introduced into the NTFS file system that allows files and directories to be selectively scrambled for local storage.

Nibble Mode: Sends the 8-bit byte of data to the printer in two cycles, each of which carries four bits, or a nibble of data. This method requires software support and more overhead on the part of the host computer. Even slower than compatibility mode, ranging from 50KB to 65KB/sec.

Nibble: Any combination of four zero’s or ones.

Northbridge: The faster of the ICs in the chipset that is responsible for managing RAM, cache and AGP functions.

Object Counter: In Performance Monitor, it is the specific property or variable for which data is being collected.

Object: In reference to the OS, an object is any single resource on the system and/or network, including files, users or devices.

Online content: The overall availability of resources across an intranet or the Internet.

Open-ended question: A question that will provide further insight into the discussion as a result of the answer provided.

Operating System: A program running on a computer system that manages all of the services required by applications that are to run on the system and interfaces with the hardware.

Optical Resolution: The number of dots per inch that can be physically interpreted by an imaging device.

Optical Stylus: A mechanism consisting of a laser emitting diode coupled to a beam splitter.

Optomechanical mouse: A mouse that uses perforated wheels passing in front of an LED to generate pulses of light that are used to track movement along the X and Y axis.

Originate Modem: The device that initiates a call.

Output: Data that is being transmitted by one device to another once that data has been processed.

Overclocking: A technique of forcing a CPU or system bus to run faster than its rated speed in order to extract maximum performance.

Page Fault: A non-critical error state that occurs when the OS looks for data in the paging file and fails to locate it.

Page Frame: 64KB of high memory that is used for moving data down from addresses above 1MB into the 640K used by DOS programs.

Page Read/Write: When physical RAM is a system becomes full, data will be temporarily stored in a file called the paging file. A Page Read is a read operation from this file, while a Page Write is when data is moved from RAM to the paging file.

Page: The amount of data that can be moved on a single memory read/write cycle; usually between 1 to 20KB.

Parallel communications: The act of transferring an entire byte of data on a single cycle, using eight separate conductors.

Parity Block: A data set that represents a mathematical image of data stored elsewhere in a RAID array.

Parity block: A mathematical image of data that can be used to reconstruct that data in the event it is lost.

Parity: An error checking mechanism that simply counted the number of 1s in a byte of data. A ninth bit is available on a parity chip for the parity bit. With odd-parity checking, if an even number of 1s is found in the byte, a 1 is placed in the parity bit to keep the number of 1s odd. With even-parity, a 0 would be placed in that position to keep the number of 1s even.

Partition: Logical sections on a hard disk that divides the overall disk space into multiple logical drives.

PC Card: Any auxiliary device designed to be plugged into a PCMCIA slot.

Peak Burst Bandwidth: A specification, measured in megahertz or gigahertz, that defines how many bits per second can be moved over the memory bus.

Permissions: Resource access or actions for which a particular user is allowed.

Permissions: The degrees of access a particular user has been granted to a specific resource on the network.

Phase Change Layer: The recording layer of a CD-RW disk.

Phase Change Printer: A printer that vaporized solid inks before applying them to paper.

Phosphor: A single dot of color created when the phosphorous layer of a CRT is excited by electrons:

Photoresist: A substance that becomes soluble after being exposed to light that falls within a specific range of wavelength.

Piezoelectric crystal: A substance that changes shape when exposed to electricity.

Pinned List: A list of shortcuts to applications that are used on a regular basis.

Pit: A tiny hole embedded in the recording layer of optical media that prevents the laser from reflecting back into the photoelectric sensor.

Pixel: The collection of phosphors that collectively generate a single dot of color in a monitor’s image.

Platen: The hard cylinder that supports the paper on impact printers.

Platter: One of two or more physical disk structures installed in a typical hard drive.

Plenum: An architectural term referring to the space between the ceiling of one floor in a building and the floor of the one above it.

Pointer: A line of code used by UFS to map a cluster used by a specific file.

Polarity: The characteristic of an electrical circuit to have one point of relative positive charge (or pole) and another point of relative negative charge (or pole).

Port Replicator: A device to which a laptop computer can be attached that provides additional I/O services to the computer.

Port: A logical address added to each segment of data transmitted that indicates what application or protocol is expecting the data.

P-rating: short for performance rating, this was a labeling method that, instead of designating a CPU by its clock speed, labeled it as the Intel CPU that it could be compared to, even though the actual clock speed and bus speed were both lower.

Preemptive Multitasking: A form of managing multiple applications on a computer system that puts the responsibility for releasing system resources onto the OS.

Prefetch: The subcomponent of a microprocessor that is responsible for retrieving data and moving it into the CPU.

Pregroove: A spiral track engraved on CDR and CD-RW media at the factory that acts as a target for the recording laser.

Print head: The mechanism on any impact or inkjet printer that is responsible for depositing the pigment onto the paper.

Priority boosting: A process by which the privilege level of a thread of code is promoted to a higher level in order to enhance its chances at the CPU.

Privilege level: A level of protection and priority that certain lines of code running within an OS have over other lines of code.

Privileges: The rights a particular user has been granted to perform specific function or tasks on a system or the network in general.

Processing: Any manipulation of data that can occur between the time the data has been inputted into the computer and the time that is provided as output. Processing can consist of calculations performed on the data, replication of that data to alternative locations and the comparison of one data set to another. Not all processing is done by the CPU.

Processor ring: Another term for privilege level.

Product Activation: A newer technology that requires the end user to physically activate their product through a database managed by the product’s manufacturer. This prevents the product from being installed on multiple machines.

Profile: Various settings and preferences specific to particular user or piece of hardware on a system.

Promiscuous Mode: An operating mode for any network interface in which all incoming packets will be accepted, even if they are not intended for that specific interface.

Protected Mode: A function of a CPU that prevents two separate programs from seeing each other’s code or from attempting to use overlapping memory addresses. Should either event occur, the CPU would lock up.

Pthalocyanine dye: A more stable dye used in recent generations of CDR that is less sensitive to UV light and lasts for up to a hundred years.

Quad-pumped: A technique of moving four bits of data over each wire on each clock cycle of the front side bus.

RAS/CAS delay: The delay that occurs between RAS and CAS. Also known as CAS latency.

Raster Line: A single row of pixels that make a horizontal line across an image.

Read Power: The lowest power setting for the optical stylus of a CD-RW, which it uses to read data from the surface.

Real Mode: An operational mode for either a CPU or an OS in which an only one application can be present on the system at once and only 1MB of RAM can be addressed by that application.

Real time OS: An OS designed to be able to perform specific functions at the precise time at which those functions are needed.

Receive Modem: The device that is being called.

Recognition Scan: A BIOS routine that polls each devices installed on a computer system to see if that device is Plug ‘n Play, and if so, what resources it currently claims.

Rectifier circuit: A specialize series of components that converts AC current to DC current.

Redirector: An OS function (usually running within a client) that intercepts hardware and software calls that are intended for a remote device and points them in the right direction.

Refresh Rate: The number of columns of memory cells per cycle that the MCC will recharge.

Refresh: The process of recharging the capacitors that link to the transistors of each memory cell on a chip.

Registry: In Windows, it is a relational database that contains all system and application settings and/or parameters.

Repeater: A device that cleans up, amplifies and retransmits a signal, effectively increasing the distance data can travel over any given medium.

Report phase: A part of the WIN2K installation procedure that seeks out and logs programs and device drivers that are likely to cause problems.

Resident Command: In an OS, it is any command that is an integral part of the command interpreter and does not require an external executable program.

Resistance: The tendency for a substance to block the flow of electrons.

Resistor: An electrical component that restricts the flow of current by a precisely measured amount.

Restore Point: A copy of system files and registry entries that were in place at the time a major system change was introduced.

Riser: A specialized expansion card that supports other expansion devices such as PCI or ISA cards horizontally, parallel to the motherboard, in order to save space.

Root Directory: The volume description, into which all other directories and files will be store.

Root Frequency: The single frequency of any given musical note that makes that note sound the way it does, regardless of what instrument plays it.

Router: A device that interconnects two autonomous networks into a single larger network.

Sag: A sudden transient decrease in voltage.

Scatter-gather data transfer: The ability of a device to execute a command on one set of data and output the results to multiple devices.

SCSI Expander: A device that allows a technician to effectively increase the length of a SCSI chain without the risk of data corruption.

Sector: the smallest data storage unit recognized by a disk on a hard drive. On magnetic media, the sector is consistently 512 bytes. It can vary between different types of optical media.

Sector: The smallest readable unit of data on a magnetic disk drive. A sector consists of 512 bytes.

Security Descriptor: A token attached to a resource that defines security attributes assigned to that resource.

Segment Register Cache: Separate cache locations maintained by Pentium II (and later) for keeping 16-bit code running separately from 32-bit code.

Semiconductor: A substance that exhibits the characteristics of both a conductor and a resistor, depending of the amount of voltage passing through.

Serial communications: The act of transferring data a single bit at a time over a single connection.

Server: Any device or software that provides services to other devices or pieces of software that need them.

Shadow Mask: A thin metal sheet perforated with tiny holes that outlines the individual phosphors in a CRT monitor.

Share Level Security: A method of protecting resources on the network that involves applying the security attributes, such as password protection, to the object itself. As such each secured object on the system may have a unique password.

Sideband Addressing: The ability of a device to send and receive data in a single memory access.

Signal Saturation: The maximum strength of recording signal that a device can handle before the recording becomes unusable.

Simplex: A communications method by which a device can either transmit or receive but cannot do both.

Single-ended signaling: A method by which a single data wire on a parallel cable is matched up by a ground wire.

Single-mode fiber: A fiber optics strand that moves only a single signal through the core.

Slot: A mounting assembly designed to support edge-card mounted devices. Also, On a CD-ROM (or similar) drive, it is a form of loading mechanism that engages a CD when it is inserted into the opening and draws the disk into the drive.

Snap-in: An applet that can be added to customized consoles in Microsoft Management Console.

Snapshot: In reference to an OS, it is a small binary file that contains information useful in replication the organization and structure of an application or configuration.

Socket Driver: The portion of a PC card driver that is responsible for I/O services and insertion/removal notification.

Socket: A mounting assembly designed to support pin-mounted devices.

Soft Fault: The data requested by the CPU is in memory, but not part of the current working set of data. As a result a new memory search must be initiated.

Southbridge: The slower of the ICs that make up the chipset. The Southbridge manages serial and parallel communications, USB, and most of the expansion slots.

Spanned volume: A larger logical drive that is created by combining space located on two different partitions or disks.

Spare Sectoring: A technique hard drive manufacturers use in which extra tracks of recordable space are included with each drive that ships. As bad sectors are discovered on the drive, new sectors are made available from this space to replace the bad ones.

Speculative Execution: When two different subroutines have been loaded by branch prediction, Speculative Execution will actually process the lines of each branch loaded.

Speed Mismatch Compatibility: A technology that allows two devices on the same bus to operate at different speeds and still successfully communicate with one another.

Spike: A sudden transient increase in voltage.

Standby power supply: A device that uses a generator to provide electrical current to a room or building in the event of a total power failure.

Starting delimiter: A single bit at the beginning of a data byte being transmitted asynchronously that marks the beginning of the byte.

Stepper Motor: A motor that has been designed in such a way that, rather that rotating smoothly, jumps from one position to another in precisely measured increments.

Stop Code: A number assigned to a particular catastrophic event, along with certain parameters that further define the event.

Streaming SIMD: The ability of certain CPUs to execute an instruction only once, but apply that instruction to several sets of data.

Striped volume: A logical drive that is created by storing data in chunks that are distributed among multiple physical drives.

Subdirectory: any directory that exists beneath another directory.

Subharmonics: Sound frequencies below the root frequency that are generated by an instrument or voice when a certain note is generated.

Subnet Mask: A configuration setting within TCP/IP that identifies to the system what part of an IP address is the network address and what part is the host address.

Substrate: The supportive material over which an active substance can be applied.

Supervisory mode: A process by which an OS runs code at the highest possible privilege level.

Surge Suppressor: A device that is able to filter out voltages surges and prevent them from reaching the devices plugged into their outlets.

Swap File: The file on the hard disk that stores the data reserved in Virtual Memory.

Switch: A device that breaks a larger network down into smaller segments, isolating each segment into its own collision domain.

Switch: in reference to an OS, it is an additional parameter added to the end of a command that defines advanced functions for that command to perform. The switch turns a specific function on or off.

Synchronization bits: Data included on each sector of a data CD that assures that the information will be processed in the correct sequence.

Synchronous communication: A form of serial communication that transmits large amounts of data at once in packets.

Synchronous timing: Bus speeds are a sub-multiple of the CPU’s clock speed and data is delivered at a steady rate based on that speed.

SYSINIT: A subroutine of IO.SYS that seeks out and runs MSDOS.SYS during the MS-DOS boot process.

System call: a request for a service not directly provided by the application.

System Object: On a system in general, it is any hardware or software entity to which specific properties can be assigned. In Performance Monitor, it is a category of events that can be monitored.

System Virtual Machine: An environment in Windows that emulates a complete computer system and houses all of the critical processes and functions of the OS.

Target: Any device that is to be the intended recipient of data.

Task Scheduler: A system file that determines how long a particular application can retain control of system resources.

Task switching: The ability of an OS to close a program, run another, and then return to the same point in the program previously closed.

Terminate: To create a dead end for electrical signals traveling down a wire so that they do not echo back the other direction.

Texel: A small clip that serves as the sample of a texture used in texture mapping.

Texture mapping: A process by which pre-drawn textures are stored in memory and applied to an image as needed.

Thermal Printer: A printer than ejects ink onto a page of paper by heating the fluid.

Thicknet: A name commonly given to RG-8 coaxial cable

Thin-film Metal: A metalized magnetic medium applied by evaporating metal and allowing it to “condense” back onto the surface being coated.

Thinnet: A name commonly given to RG-68u coaxial cable

Third-party DMA: Direct memory access that is managed by a device other than the two devices utilizing DMA to exchange data.

Threshold Voltage: The amount of electrical differential required to move a semiconductor from a state of resistance to a state of conductance.

Thunking: A Microsoft process of translating 16-bit commands and data into a 32-bit format, and vice versa.

Topology: The method through which a network is physically wired.

Trace: The fine copper path seen on printed circuit boards that acts as a conductor for a signal.

Track: A virtual circle of sectors on a magnetic drive that makes a complete ring around the disk surface.

Trackpad: A pointing device used on laptop computers that makes use of an electrostatically sensitive surface. The user runs a finger across the surface and the trackpad tracks the movement of the electrostatic charge.

Trackpoint: A small pointing device used on laptop computers, similar to a trackball, but much smaller.

Tractor Feed: A paper transport mechanism that uses a set of gears on a printer to advance the paper by engaging in perforations along each side of the paper.

Tranceiver: Any device that is designed to be able to either transmit or receive data.

Transient Command: A command that is issued and run from an external source.

Transistor: A microscopic on/off switch that uses the electrical characteristics of a semiconductor to reverse positions.

Transition Cell: the minimum number of particles that can be affected by a single magnetic flux.

Transmission rate: The number of bits per second that is being transmitted.

Tray: On a CD-ROM (or similar) drive, it is a form of loading mechanism that consists of a platform that ejects when the user pushes a button, and retracts with the CD in place.

Triad: The three separate phosphors, each of a separate primary color, that when combined form the separate hues of color perceived by the user.

Trigger: Another name for a switch.

Trojan Horse: A malicious program designed to mimic another commonly recognized program that is, in fact, performing some other action in the background without the knowledge or consent of the user.

Tunnel Erasure: A technique of erasing the magnetic charge from the edges of a recorded track on a magnetic disk.

Typeface: The basic shape that letters and numbers of a particular character set will assume.

Ultra-wide SCSI: SCSI over a 32-bit bus.

Unbounded Media: Any medium that connects the device to the network using energy forms that travel through air and/or space.

Uninterruptible power supply: A device that uses batteries to provide electrical current to another device in the event of a total power failure.

Upgrade: The replacement of an older OS with a newer, migrating as many settings and applications as possible.

USB Device: Any component designed to be operated on the USB bus.

USB Host: Any computer or other device equipped with USB compatible BIOS, firmware and controller.

USB Hub: A device that manages the I/O for two or more USB device chains.

User Level Security: A method of securing resources on a system or network that involves assigning the security attributes to an account provided to the user. Once the user has logged on, access to resources is provided based on the permissions assigned to the account.

User Mode: An operational mode for an OS that manages applications and security functions.

Vampire Clamp: A device consisting of two halves that screw together. One half is fitted with sharp teeth that bite through the insulation of RG-8 cable.

Vapor Deposition: The process of applying a metal coating by the process of evaporation.

Virtual machine: An environment set up in system memory that emulates all functions of a working computer, providing the illusion that a program is the only code running on a computer system.

Virtual Memory: A slice of hard drive space that is reserved for the OS for temporary storage of data needed by dormant programs that is treated as if it were system memory.

Virtual Real Mode: A technique of creating separate address spaces and time slicing the CPU time so that legacy applications think they’re the only programs running on the machine, even though there may be several running at once.

Voice Coil: An extremely fast and highly accurate motor that works by applying a electrical current to a tightly wrapped coil of wires surrounding, but not touching a permanently magnetized cylinder. When current is applied to coil, the cylinder rotates. Negative voltage rotates the cylinder one direction; positive the other. The amount of voltage determines how far the cylinder moves.

Volatile: Unstable or changeable. Requires constant power in order to continue to exist.

Voltage: The difference in charge between to objects or surfaces. This is sometimes referred to as electrical pressure.

Volume set: A single logical disk drive that is created when multiple partitions or physical disk are combined.

Volume Set: A storage array of very large capacity created by combining multiple drives of smaller capacity.

Volume: A single managed unit of storage on a computer system. This can be a single disk, if that disk has been formatted to only one partition, or it can be an individual partition on a disk.

Warm: A shift in the color of an image toward the red side.

White Balance: A measurement of how pure the reproduction of white is accomplished in an image.

Wide SCSI: SCSI over a 16-bit bus.

Wild card: a character that instructs a command to replace that character with any other character or collection of characters it finds in its place.

Word: The amount of data that can move across the CPU’s external data bus in one clock cycle; usually between two and four bytes.

Workgroup: a collection of devices on the network that share common resources and responsibilities.

Write Power: The highest power setting for the optical stylus of a CD-RW, which it uses to recorod data onto the surface.

Write Protect: A process or mechanism that prevents the data on a disk or other medium from being erased or overwritten.

Zone Recording: A technology that allows the sectors on the outer tracks of a hard disk to be the same physical size as those toward the center. This allows for far more sectors per track on the outer tracks.