analog  A method of signal representation by an infinitely smooth universe of numeric values. Measurements that are characterized as analog include readings of voltage and current. Compare with digital.

analog video  A video signal that represents an infinite number of smooth gradations between given video levels. Compare with digital video.

anamorphic  Unequally scaled in vertical and horizontal dimensions.

Animated GIF  A single GIF file composed of several images and animated. Animated GIFs are supported by most browsers but are limited in their flexibility and control. However, Animated GIFs generally have a smaller file size than other animation files, such as Java Applets or QuickTime movies. It is currently the most popular animation method for the Web

ANSI  American National Standards Institute. A standards-setting, non-governmental organization that develops and publishes standards for voluntary use in the United States.

anti-aliasing  A form of interpolation used in graphics display technology when combining images; pixels along the transitions between images are averaged to provide a smooth transition.

API  Application programming interface. A set of routines that an applications program uses to request and carry out lower-level services performed by a computer operating system.

Application  Software that lets users do relatively complex tasks, as well as create and modify documents. Common application types include word processors, spreadsheets, database managers, and presentation graphics programs.

APM  Advanced Power Management. A software interface (defined by Microsoft and Intel) between hardware-specific power management software (such as that located in a system BIOS) and an operating system power management driver. Replaced by ACPI as the system interface under Microsoft® Windows® 98 and Windows 2000.

Apple  too many people confuse "Apple" with the "Macintosh". Apple is the company that makes Macintosh computers. These include Power Macs, PowerBooks, iMacs, and iBooks. And no, Apple is not going out of business. In fact, the company's recent rate of growth far outpaces the industry average. With the new iBook and the upcoming line of Power Mac G4s, Apple is poised for a very bright future. To hear the latest on what's going on over at Apple Computer, check out their website.

Applet  A Java program that can be "embedded" in a web page. The difference between a standard Java application and a Java applet is that applets can't access system resources on the local computer. This means files and serial devices (modems, printers, scanners, etc.) cannot be called or used by the applet. Applets have helped make the web more dynamic and functional as well as giving an enormous boost to the Java programming language.

architecture  A general term referring to the structure of all or part of a computer system. Also covers the design of system software, such as the operating system, as well as referring to the combination of hardware and basic software that links machines on a computer network.

ASCII  American Standard Code for Information Interchange. The most popular coding method used by small computers for converting letters, numbers, punctuation, and control codes into digital form.

asynchronous  An operation that proceeds independent of any timing mechanism, such as a clock. Compare with synchronous.

ATA  AT Attachment. A disk drive implementation that integrates the controller on the disk drive itself. Also known as IDE.

ATAPI  AT Attachment Packet Interface. A hardware and software specification that documents the interface between a host computer and CD-ROM drives using the ATA bus.

ATM  Asynchronous transfer mode. A transmission protocol that segments user traffic into small, fixed-size units called cells, which are transmitted to their destination, where they are reassembled into the original traffic. During transmission, cells from different users may be intermixed asynchronously to maximize utilization of network resources.

audio class  The class of filters that deals with pulse code modulation or similar digitized data or analog signals. A WDM audio minidriver provides support for audio devices under the WDM audio architecture.

audio mixing  The method of combining multiple streams of audio data into a single stream through some method such as addition and clipping.

AUI  Attachment Unit Interface. The portion of the Ethernet standard that specifies how a cable is to be connected to an Ethernet card. AUI specifies a cable connected to a transceiver that plugs into a 15-pin socket on the network adapter.

B

Backbone  Network used to interconnect several networks together.

bandwidth  The amount of data that can be transmitted in a fixed amount of time. For digital devices, the bandwidth is usually expressed in bits or bytes per second (bps). For analog devices, the bandwidth is expressed in cycles per second, or Hertz (Hz).  Bandwidth is usually measured in bits-per-second. A good example of this is a highway with cars travelling on it. The highway is the connection and the cars are the data. The wider the highway the more cars can travel on it at one time. It's the same thing with computer data. Full-motion, full-screen video would require a bandwidth of roughly 10,000,000 bits-per-second.

Baud  A unit of measurement that denotes the number of bits that can be transmitted per second. For example, if a modem is rated at 9600 baud it is capable of transmitting data at a rate of 9600 bits per second. The term was derived from the name of J.M.E. Baudot, a French pioneer in the field of printing telegraphy.

Binary  This is a two-digit (Base-2) numerical system, which computers use to store data and compute functions. The reason computers use the binary system is because digital switches inside the computer can only be set to either on or off, which can be easily represented by a 1 or 0. Though binary consists of only 0's and 1's, the two digits can be used to represent any number. For example, 0 in binary represents 0, 1 represents 1 (2^0), 10 represents 2 (2^1), 11 represents 3 (2^1 + 2^0), 100 represents 4 (2^2), 101 represents 5 (2^2 + 2^0), 110 represents 6 (2^2 + 2^1), 111 represents 7 (2^2 + 2^1 + 2^0), 1000 represents 8 (2^3), etc.

BIOS  Basic input/output system. A set of routines that works closely with the hardware to support the transfer of information between elements of the system, such as memory, disks, and the monitor. Although critical to performance, the BIOS is usually invisible to the end user; however, programmers can access it.

Bit  The name supposedly comes from Binary DigIT. A bit is a single digit number in base-2 (0 or 1) and is the smallest unit of computer data. A full page of text is somewhere around16,000 bits. The most common area where bits are used intstead of bytes, is to measure bandwidth (in bits-per-second). Why? Probably because it makes your Internet connection sound faster than it really is. Abbreviation: "b".

Bit Depth  The number of bits used to represent each pixel in an image, determining its color or tonal range.

bitmap  Representation of characters or graphics by individual pixels arranged in rows (horizontal) and columns (vertical). Each pixel can be represented by either 1 bit (simple black and white) or up to 32 bits (high-definition color).

bit-mapped graphics  Images created with matrices of pixels or dots. Also raster graphics.

bit specifications  Number of colors or levels of gray that can be displayed at one time. Controlled by the amount of memory in the computer's graphics controller card. An 8-bit controller can display 256 colors or levels of gray; a 16-bit controller, 64,000 colors; and a 24-bit controller, 16.8 million colors.

Bookmark  Similar to a real-life bookmark, an Internet bookmark acts as a marker for a website. When using a web browser, you can simply choose a bookmark from the browser's menu to go to a certain site. This way, you don't have to do the redundant typing-in of the URL every time you visit one of your favorite sites. So how do you create a bookmark? Well, in most browsers, you simply choose "Add Bookmark" from the Bookmarks menu when you're at a page which you'd like to bookmark.

bpp  Bits per pixel. The number of bits used to represent the color value of each pixel in a digitized image.

bps  Bits per second. The number of bits transferred per second in a data communications system. A measure of speed.

brightness  The value associated with a pixel, representing its gray value from black to white.

Broadcast Architecture  The set of technologies that enable PCs to receive broadcast data.

Browser  It's what your probably using to read this. A browser, or web browser - same thing, is the program people use as their interface to the World Wide Web. It interprets HTML code including text, images, hypertext links, java applets, etc. allowing you to view web sites and navigate from one to another. Currently, the two most popular browsers are Netscape Communicator and Microsoft Internet Explorer.

buffer  A reserved portion of memory in which data is temporarily held pending an opportunity to complete its transfer to or from a storage device or another location in memory.

Bus This computer hardware term refers to the collection of wires through which data is transmitted from one part of a computer to another. A bus is essentially an electronic data highway inside your computer. In personal computers, Bus usually refers to internal bus. The internal bus connects all the internal computer components to the CPU and main memory. Expansion boards may access the CPU and memory through an expansion Bus.

bus enumerator  In a non-ACPI Plug and Play system, a bus device driver that detects devices located on a specific bus and loads information about devices into the hardware tree.

Byte  A set of bits that represent a single character in the computer's memory. There are 8 bits in a byte

C

Cable Modem  Though a cable modem serves the same purpose as your typical analog modem, a cable modem is different in many ways. The biggest difference is that a cable modem is much faster. While a 56K modem can receive data at about 53 Kbps, a cable modem can haul it in at about 1.5 Mbps. That's about 30 times faster. Though the actual Internet bandwidth over a cable TV line is up to 27 Mbps for downstream to the subscriber and about 2.5 Mbps upstream, since the local provider may only have a T1 connection , which maxes out at 1.5 Mpbs, that will be the maximum transfer rate for the suscriber. Also, a cable modem doesn't hook up to a phone line; it connects to a local cable TV line, hence the term cable modem. This allows computers equipped with a cable modem to have a continuous connection to the Internet. No dialing the ISP everytime you want to check your e-mail. Cable modems, which have a much more complex design than telephone modems are usually external devices, but they can be integrated within a computer or set-top box. Finally, instead of connecting to a serial port, cable modems attach to a standard 10Base-T Ethernet card so that they can transfer data at the fastest speed possible.
The way the cable modem system works is pretty complex. All of the cable modems attached to a coaxial cable line owned by some cable TV company communicate with the company's Cable Modem Termination System (CMTS). All cable modems connected to the main line can receive from and send signals only to the CMTS, not to other cable modems on the line.

cache  An area of RAM reserved for data recently read from disk, which allows the processor to quickly retrieve it if it's needed again. A special high-speed storage mechanism in which frequently used data values are duplicated for quick access. It can be either a reserved section of main memory or an independent high-speed storage device. Two types of caching are commonly used in personal computers: memory caching and disk caching.

Caching A process in which frequently accessed data is kept on hand, rather than constantly being from the place where it is stored.

Card Services  Under Windows, a protected-mode system component that is a VxD linked with the PC Card bus driver. Card Services passes the event notification from socket services to the PC Card bus driver, provides information from the computer's cards to the PC Card bus driver, and sets up the configuration for cards in the adapter sockets.

CCD Charge-coupled device. An integrated, micro-electrical light-sensing device built into some image capturing devices.

CCITT  Comite Consultatif Internationale de Telegraphie et Telephonie (Consultative Committee for International Telephone and Telegraph). An international standards organization dedicated to creating communications protocols that will enable global compatibility for the transmission of voice, data, and video across all computing and telecommunications equipment.

CD-I  Compact Disc Interactive. A compact disc format (developed by NV Philips and Sony Corporation) that provides audio, digital data, still graphics, and limited-motion video.

CD-ROM  Compact disc read-only memory. A 4.75-inch laser-encoded optical memory storage medium (developed by NV Philips and Sony Corporation) with the same constant linear velocity (CLV) spiral format as compact audio discs and some videodiscs. CD-ROMs can hold about 550 MB of data.

CD-ROM One Off (or CD-R)  This is a write once CD that can be read from standard CD-ROM drives. This is the type of CD that is used to generate CD-ROM check disks

CE-PC  Old code name for the PC-based hardware development platform.

CGI  Stands for "Common Gateway Interface." CGI is a set of rules for running external programs in a web server. Whenever you submit information, like search terms or your login and password, to a web server, there's a good chance that it's using CGI to receive and process the data.

chroma, chrominance  (1) The color portion of the video signal that includes hue and saturation information. Requires luminance, or light intensity, to make it visible. (2) Hue is defined as tint. Saturation indicates the degree to which the color is diluted by luminance (or by white light). Compare with luminance.

CI  Component Instrumentation. A specification for DMI related to the service layer.

CIE  Commission International de l'Eclairage. The international commission on illumination. Developer of color matching systems.

CIM  Common Information Model. Describes the WBEM data representation schema that is now a DMTF-sponsored industry standard. CIM evolved from HMMS (HyperMedia Management Schema).

CIMOM  CIM Object Manager. A key component of the WBEM architecture. A central message of WBEM is uniform data representation encapsulated in object-oriented fashion in the CIM. CIMOM provides a collection point and manipulation point for these objects. Formerly HMOM.

class  For hardware, the manner in which devices and buses are grouped for purposes of installing and managing device drivers and allocating resources. The hardware tree is organized by device class, and the operating system uses class installers to install drivers for all hardware classes.

class driver  A driver that provides system-required, hardware-independent support for a given class of physical devices. Such a driver communicates with a corresponding hardware-dependent port driver, using a set of system-defined device control requests, possibly with additional driver-defined device control requests. Under WDM, the class driver creates a device object to represent each adapter registered by minidrivers. The class driver is responsible for multiprocessor and interrupt synchronization.

CMYK  Cyan-magenta-yellow-black. A mixing model or method of describing colors used with many printing systems. Uses subtractive primaries, starting with white and subtracting percentages of cyan (blue), magenta (red), and yellow to yield desired colors.

Coaxial Cable  A type of cable that contains two conductors. The center conductor is surrounded by a layer of insulation, which is then wrapped by a braided-metal conductor and an outer layer of insulation.

codec  Coder-decoder. A filter for data that manipulates it in some form, usually by compressing or decompressing the data stream. 

color keying  To superimpose one image over another for special effects.

COM  (1) Component Object Model; the core of OLE. Defines how OLE objects and their clients interact within processes or across process boundaries. (2) Legacy serial port.

COM device  See serial (COM) device.

compatibility mode  An asynchronous, host-to-peripheral parallel port channel defined in the IEEE 1284-1944 standard. Compatible with existing peripherals that attach to the Centronics-style PC parallel port.

compatible ID  An ID used by the Plug and Play Manager to locate an INF to install a device if there was no match on the hardware IDs for the device.

composite video  A signal that combines the luminance, chrominance, and synchronized video information onto a single line. This has been the most prevalent NTSC video format.

compressed video  A digital video image or segment that has been processed using a variety of computer algorithms and other techniques to reduce the amount of data required to accurately represent the content and thus the space required to store the content.

compression  The translation of data (video, audio, digital, or a combination) to a more compact form for storage or transmission.

connection  A negotiated method of communication between devices, whether implemented in hardware or software.

contrast  The range of light and dark values in a picture; or a measure of brightness content in an image. The range between the lightest tones and the darkest tones in an image.

control method  A definition of how an ACPI-compatible operating system can perform a simple hardware task. For example, the operating system invokes control methods to read the temperature of a thermal zone. Control methods are written in an encoded language called AML.

convergence  In an RGB monitor, where red, green, and blue signals all converge in one pixel. At full convergence, the RGB pixel would be white.

Cookie   data sent to your computer by a web server that records your actions on a specific web site. It's a lot like a preference file for a program on your computer. Whenever you visit the site after being sent the cookie, the site will load according to the information stored in the cookie. For example, some sites can remember information like your user name and password, so you don't have to re-enter it each time you visit the site. Cookies are what allow you to have personalized web sites like "My Excite" or "My Yahoo" in which you can customize what is displayed on the page.

CPU  Central processing unit. A computational and control unit of a computer; the device that interprets and executes instructions. By definition, the CPU is the chip that functions as the "brain" of the computer.

Cross Platform   A multimedia program that is authored to play on a number of platforms. Cross Platform usually refers to programs that run on both Windows and Macintosh systems

CSA  Connection and Streaming Architecture. Kernel-mode streaming in WDM.

CSN  Card Select Number. The handle created by the system BIOS or the operating system through the isolation process and assigned as a unique identifier to each Plug and Play card on the ISA bus.

D

Daughterboard A board that attaches to (rides piggyback on) another board, such as the motherboard or an expansion card. For example, you can often add a daughtercard containing additional memory to an accelerator card.

Database  A file created by a database manager that contains a collection of information organized into records, each of which contains labeled categories (called fields).

DAT  Digital audio tape. A consumer recording and playback medium for high-quality audio.

data rate  The speed of a data transfer process, normally expressed in bits per second or bytes per second.

DDC  Display data channel. The Plug and Play baseline for monitors. The communications channel between a monitor and the display adapter to which it is connected. This channel provides a method for the monitor to convey its identity to the display adapter.

decompression  To reverse the procedure conducted by compression software, and thereby return compressed data to its original size and condition. The expansion of compressed image files. See also lossy and non-lossy.

Default  This is the default term used to describe a preset value for some option in a computer program. It is used when a setting is not specified by the user. For example, the default font setting in Netscape Communicator is "Times." If you don't go to the Netscape preferences and change it to something else, the "Times" font will be used -- by default. Typically default settings in programs are set to what most people would choose, so there's no big reason to change them. However, if you're one of those people who has to customize everything and can't stand having a single option set to default, feel free to do whatever you want.

density  The degree of darkness of an image. Also, the percent of screen used in an image.

device  Any circuit that performs a specific function, such as a parallel port.

Device Bay  An industry specification that defines a mechanism for both peripheral devices and system bays that allows adding and upgrading PC peripheral devices without opening the chassis.

device ID  A unique ASCII string for the device created by enumerators to identify a hardware device and used to cross-reference data about the device stored in the registry. Distinguishes each logical device and bus from all others on the system.

device node  The basic data structure for a given device, built by the Configuration Manager. Device nodes are built into memory at system startup for each device and enumerator. Each device node contains information about the device, such as currently assigned resources.

device object  A kernel-mode-only object type used to represent a physical, logical, or virtual device whose driver has been loaded into the system.

devnode  See device node.

DIB  Device-independent bitmap. A file format designed to ensure that bitmap graphics created using one application can be loaded and displayed in another application exactly the way they appeared in the originating application.

digital  A method of signal representation by a set of discrete numerical values, as opposed to a continuously fluctuating current or voltage. Compare with analog.

digital video  A video signal represented by computer-readable binary numbers that describe a finite set of colors and luminance levels. Compare with analog video.

digitization  The process of transforming analog video signal into digital information.

Digitizers  A machine which converts analog data into digital data on a computer (such as a scanner digitizing pictures or text).

Directory  system that your computer uses to organize files on the basis of specific information.

disk I/O controller  Also HDC. A special-purpose chip and circuitry that directs and controls reading from and writing to a computer's disk drive.

Distance Learning  Education at home via computer-assisted communications, i.e the World Wide Web (WWW) or wide area network (WAN). Students can participate in video-conferencing/classroom sessions, send and receive work through e-mail and take part in various electronic forums. Many companies use distance learning to retrain and update their employees on many levels. They can save time and money by not physically bringing everyone together for a conference or a meeting.

DLL  Dynamic-link library. API routines that user-mode applications access through ordinary procedure calls. The code for the API routine is not included in the user's executable image. Instead, the operating system automatically points the executable image to the DLL procedures at run time.

DMA  Direct memory access. A method of transferring data between peripheral and host memory without processor intervention. The system board uses a DMA controller to handle a fixed number of channels, each of which can be used by only one device at a time.

DMF  A special format for 3.5" floppy disks that permits storing 1.68 MB of data on a standard 1.44-MB disk. This enables Microsoft to provide more software on fewer disks. For example, with a product like Office 95, users will have to install eight fewer disks as a result of DMF disk compression.

DMI  Desktop Management Interface. A framework created by the Distributed Management Task Force (DMTF). DMTF specifications define industry-standard interfaces for instrumentation providers and management applications.

dock  To insert a portable computer into a base unit. Cold docking means the computer must begin from a power-off state and restart before docking. Hot docking means the computer can be docked while running at full power. See also warm docking.

docking station  The base computer unit into which a user can insert a portable computer, expanding it to a desktop equivalent. A typical docking station provides drive bays, expansion slots, all the ports on an equivalent desktop computer, and AC power.

Domain Name  The name that identifies an Internet site. For example, "apple.com" is the domain name of Apple Computer's home page. A single server may have more than one domain name, but a single domain name points to only one machine. To use Apple Computer as an example again, www.apple.com, support.apple.com, and store.apple.com could be served on one to three machines. It is also possible, and quite common, for a domain name to be registered, but not be connected to an actual machine. The reason for this is usually so that a company or group can have e-mail addresses at a certain domain without having to maitain a web site.

dongle  A physical device, attached to a PC's I/O port, that adds hardware capabilities.

Download  The process in which data is sent to your computer. Whenever you get information off the Internet, you are downloading it to your computer. For example, you might have to download an upgrade for your computer's operating system in order to play a new game (especially if you're using Windows). The opposite of this process, sending information to another computer, is called uploading.

DPC  Deferred procedure call. Method used in Windows NT® and Windows 2000 for event scheduling.

driver  Kernel-mode code used either to control or emulate a hardware device.

driver stack  Device objects that forward IRPs to other device objects. Stacking always occurs from the bottom up and is torn down from the top.

DSL Stands for "Digital Subscriber Line." It's basically another medium for sending data over regular phone lines. However, a DSL circuit is much faster than a regular phone connection, even though the wires it uses are copper like your typical phone lines. An asymmetric DSL (ADSL) connection allows download speeds of up to about 1.5 megabits (not megabytes) per second, and upload speeds of 128 kilobits per second. That is why it's called ADSL and not just DSL. There is also a "Symmetric Digital Subscriber Line" (SDSL) which is similar to ADSL, but allows data transfer speeds of 384 Kilobits per second in both directions. Theoretically, this type of connection allows download speeds of up to 9 megabits per second and upload speeds of up to 640 kilobits per second. The difficult part in establishing an DSL circuit is that it must be configured to connect two specific locations, unlike a regular phone line or cable modem. DSL is often seen as a better alternative to ISDN.

DSP  Digital signal processor. An integrated circuit designed for high-speed data manipulations. Used in audio, communications, image manipulation, and other data-acquisition and data-control applications.

DVD  Stands for "Digital Versatile Disc." Optical disk storage that encompasses audio, video, and computer data.  a high-capacity optical disc that looks like a CD, but can store much more information. While a CD can store 650 MB of data, a single-layer, single-sided DVD can store 4.7GB of data. This allows for massive computer applications and full-length movies to be stored on a single DVD.

dynamic detection  The process by which a system can detect that a new device has been added or removed from the PC. This process allows the operating system and applications to immediately begin using the added devices or stop using the removed devices without rebooting the system.

E

ECP  Extended capabilities port. An asynchronous, 8-bit-wide parallel channel defined by IEEE 1284-1944 that provides PC-to-peripheral and peripheral-to-PC data transfers.

EISA  Extended Industry Standard Architecture. A 32-bit PC expansion bus designed as a superset of the ISA bus. Designed to expand the speed and data width of the legacy expansion bus while still supporting older ISA cards.

embedded controller  The general class of microcontrollers used to support OEM-specific implementations, mainly in mobile environments. The embedded controller performs complex low-level functions through a simple interface to the host microprocessor(s).

embedded controller interface  ACPI defines a standard hardware and software communications interface between an operating system driver and an embedded controller--for example, Smart Battery and AML code. This allows any operating system to provide a standard driver that can directly communicate with an embedded controller in the system, thus allowing other drivers to communicate with and use the resources of system embedded controllers.

Ethernet  is the most common type of connection computers use in a local area network (LAN). The two most widely-used forms of Ethernet are called 10BaseT and 100BaseT. In a 10BaseT Ethernet, data transfer speeds can reach 10 mbps (megabits per second) through a copper cable. In a 100BaseT Ethernet, transfer speeds can get up to 100 mbps. (Bet you wouldn't have guesses that.) There is also a new technology called "Gigabit" Ethernet, employed by some of the latest Apple Power Macs, where data transfer rates peak at 1000 mbps.

event set  A uniquely identified set that represents a group of items about which a client can be notified.

expansion bus  A group of control lines that provide a buffered interface to devices located either on the system board or on cards that are plugged into expansion connectors. Common expansion buses included on the system board are USB, PC Card, and PCI.

expansion card  A card that connects to an expansion bus and contains one or more devices.

F

FAT  File allocation table. A table or list maintained by an operating system to keep track of the status of various segments of disk space used for file storage.

File A collection of information stored as a single document with a name, called the filename. Files have extensions that indicate the program used to create them, or the type of file they are--such as '.doc' from Word, '.gif' used for graphics files, and '.exe', that signify applications that run programs. There are many types of files, but the three most common are: 1) Text files: a letter or report or any similar document is a text file. 2) Image files: any photo or graphic 3) Program files: the files behind your software programs. These files make up software like Microsoft Word or Excel.

Fiber-Optic Cable A cable made up of thin filaments of glass or other transparent materials that can carry beams of light. Using a laser transmitter that encodes frequency signals into pulses of light, data can be sent through through these cables at the speed of light. The receiving end of the transmission translates the light signals back into frequencies which can be read by a computer. Because fiber-optics are based entirely on beams of light, they are less susceptible to noise and interference than than other data-transfer mediums.

Firewall  A firewall is used to protect a networked server from damage by those who log in to it. This can either be a computer equipped with security features, software protection (called defensive coding), or both. A firewall allows only certain messages from the Internet to flow in and out of the internal network. So, basically, it's a lot like a wall of fire.

flash (disk or drive)  A type of non-volatile memory built into the unit or available as a PC Card that can be plugged into a PCMCIA slot. Flash memory can be written in blocks or over the entire chip, making it easy to erase or update.

Font  Design types for text that determine what the style of the characters. You can often specify the size of a font, as well as some attributes such as bold or italic. An example font would be Times Roman, size 10, bold.

frame  A single screen-sized image that can be displayed in sequence with other slightly different images to create animated drawings. A video frame consists of two interlaced fields of either 525 lines (NTSC) or 625 lines (PAL/SECAM), running at 30 frames per second (NTSC) or 25 frames per second (PAL/SECAM). Film runs at 24 frames per second.

Freeware  Like shareware, freeware is software you can download, pass around, and distribute without any initial payment. However, the great part about freeware is that you never have to pay for it. No 30 day limit, no demo versions, no disabled features -- it's totally free. Things like program updaters (for minor updates) and small games are commonly distributed as freeware. Please note that freeware is copyrighted, however, so you can't go sell it as your own.

FTP  Stands for "File Transfer Protocol." It is a common and efficient method of transferring files via the Internet from one computer to another. Some common FTP programs are "Fetch", for the Mac, and "CuteFTP", for Windows. However, you can also use a web browser like Netscape to access FTP servers. Simply type the URL of the server into the location box. For example: ftp://name.of.site/ will give you a listing of all the directories of the FTP server, ftp://name.of.site/directory/ which will give you a listing of all the files available in that directory, and ftp://name.of.site/directory/filename will download the actual file to your computer. Most FTP servers are "anonymous FTP" servers which means you can log in with the user name "anonymous" and your e-mail address as the password.

full-motion video  Video reproduction at 30 frames per second (NTSC-original signals) or 25 frames per second (PAL-original signals). See also frame.

functional device  See filters.

G

Gateway  Either hardware or software that acts as a bridge between two applications or networks so that data can be transferred among a number of computers. When e-mail gets sent between two servers or when you log in to a web site, the gateway helps the connection take place. Gateway is also the name of a popular direct-order PC manufacturer.

GIF  The letters, "GIF", actually stand for "Graphics Interchange Format." GIFs are compressed graphics files and use a compression formula originally developed by CompuServe.  GIFs you see on the Web use indexed color, or a palette of a certain number of colors, which greatly helps reduce their file size. These compressed files can be quickly transmitted over a network or the Internet.

Gigabyte A gigabyte consists of roughly 1 billion bytes. To be exact, there are 1024 MB or 1,073,741,824 bytes in a gigabyte. Because of the large size of today's hard disks, storage capacity is usually measured in Gigabytes (GB).

gray scale  The spectrum (range) of shades of black that an image has.

group  In networking, an account that contains other accounts, called members. Permissions and rights granted to a group are also granted to its members.

GUI  Stands for "Graphical User Interface." The acronym is pronounced "gooey", not "gwi" or "gwee". It allows computer users to interact with their system by using a mouse instead of by typing in text at a command line. The two most popular operating systems -- Windows and the Mac OS -- are GUI based. The idea of a graphical user interface was first introduced by Apple with the Macintosh in 1984, but the idea was actually stolen from Xerox.

H

hardware tree  A record in RAM of the current system configuration based on the information for all devices in the hardware branch of the registry. The hardware tree is created each time the system is started or whenever a dynamic change occurs to the system configuration.

HDTV  High-definition TV. A proposed standard that recommends doubling the current 525 lines per picture to 1050 lines, and increasing the screen aspect ratio (that is, width to height) from the current 12:9 to 16:9, which creates a television screen shaped more like a movie screen.

high-contrast support  Part of Accessibility options set by users to indicate that they require a high degree of contrast to improve screen legibility.

high resolution  An adjective describing improvement in display image quality as a result of increasing the number of pixels per square inch.

Hit Technically, a hit is a request made to a Web server. Though many people think the term refers to the number of visits a web page gets. If a web page has 5 images on it, when the page is loaded, 6 "hits" will be recorded. One for the HTML of the web page and 5 for the images. Another way the term "hit" can be used is in reference to search engine results. When you search for a phrase and the search engine finds 2000 results, you can say there were 2000 hits and be right

Home Page  The starting point, or main page of a web site. This page usually has some sort of table of contents on it and describes the purpose of the site. For example, http://www.sharpened.net/index.html is the home page of Sharpened.net. Also, many people have a "personal home page," which is often the only page of their web site.

Host  A computer on a network that acts as a server for other computers on the network. It can be a web server, an e-mail server, an FTP server, etc. For instance, a web host is what provides the content of web pages to the computers that access it.

HSB  Hue-saturation-brightness. With the HSB model, all colors can be defined by expressing their levels of hue (the pigment), saturation (the amount of pigment), and brightness (the amount of white included), in percentages.

HTML  Stands for "Hyper-Text Markup Language." Today's software programs are created mostly in C/C++; today's web pages are created in HTML. Also known as hypertext documents, web pages must conform to the rules of the the HTML language in order to be displayed correctly in a web browser. The HTML syntax is based on a list of tags that describe the format and what is displayed on web pages. Fortunately, the HTML language is quite easy to learn. Even more fortunately, (so much for good grammar), most web page development programs allow you to create web pages via a graphical interface without having to actually write the HTML code.

HTTP  Stands for "HyperText Transfer Protocol." It is the protocol used to transfer data over the World Wide Web. Yes, that's why all web site addresses being with "http://". Whenever you type a URL into your browser and hit Enter, your computer sends an HTTP request to a Web server. The Web server then sends to you the requested HTML page.

hue  The color tint of an image. The color of the analog video signal is determined by three factors: hue, saturation, and luminance.

Hyperlink  Also referred to as 'link.' An element on a Web page or email that is 'hot', so to speak. This is normally indicated by text being underlined and colored. The cursor often changes to a hand when passed over a linked element, indicating it is hot and clicking on it takes you to another Web page or Web Site. Both text and graphics can be Hyperlinks.

Hypermedia A multimedia program that combines hypertexts with graphics, video and sound.

I

IA-PC  Intel Architecture Personal Computer. A general descriptive term for computers built with processors conforming to the architecture defined by the Intel processor family based on the 486 instruction set and having an industry-standard PC architecture.

IDE  Integrated Device Electronics. A type of disk-drive interface where the controller electronics reside on the drive itself, eliminating the need for a separate adapter card. See also ATA.

IDE/EIDE Stands for "(Enhanced) Integrated Device Electronics." It is the most widely-used hard drive interface on the market. The fancy name refers to how the IDE technology "integrates" the electronics controller into the drive itself. The IDE interface, which could only support drives up to 540 MB has been replaced by the superior EIDE technology which currently supports up to 25 GB and also allows for over twice as fast data transfer rates. The other hard drive interface is SCSI, which is faster than EIDE, but usually costs quite a bit more.

IEEE  Institute of Electrical and Electronics Engineers, pronounced "I-triple-E." Founded in 1963, IEEE is an organization composed of engineers, scientists, and students. IEEE is best known for developing standards for the computer and electronics industry.

IEEE 1394  A serial protocol that runs at speeds ranging from 100 to 400 megabits per second, depending upon the implementation. Devices that are prime candidates for IEEE 1394 include digital camcorders and VCRs, digital audio amplifiers, and video teleconferencing.

image  The computerized representation of a picture or graphic.

Image map  An image, which has various parts mapped out or separated into sections that each link to a distinct Web page or Web site when clicked. When you put your cursor over an image map and move around, you will notice changes in the address bar at the bottom of your window, indicating where the links lead.

image resolution  The fineness or coarseness of an image as it is digitized; measured in dots per inch (DPI), typically ranging from 200 to 400 DPI.

in  In terms of data flow, indicates consumption of data. An in pin is compatible with an out pin.

INF file  Information file. A file created for a particular adapter that provides the operating system with information required to set up a device, such as a list of valid logical configurations for the device, the names of driver files associated with the device, and so on. An INF file is typically provided on a disk by the device manufacturer or may be included in the operating system.

INI file  Initialization file. Commonly used under Windows 3.x and earlier, INI files have been used by both the operating system and individual applications to store persistent settings related to an application, driver, or piece of hardware. In Windows 32-bit operating systems, INI files are supported for backward compatibility, but the registry is the preferred location for storing such settings.

input class  The class of filters that provide an interface for HID hardware, including USB and legacy devices, plus proprietary and other HID hardware, under the WDM HID architecture.

Interface   Part of a computer or program: A set of dials, knobs, operating system commands, graphical display formats, and other devices which allow the user to communicate with that computer or program. A graphical user interface (GUI) gives its users a picture-oriented way to interact with technology via icons displayed on the desktop. As in: "Netscape Navigator and Microsoft Internet Explorer both have well-designed graphical user interfaces."

internet (not capitalized) The result of connecting two or more networks so that computers in each network can share data and devices. Routes connect different networks on an internet. An internet does not necessarily use TCP/IP

instance ID   A string that distinguishes a device from other devices of the same type on a computer. An instance ID is a string without any path-separator characters that contains serial-number information if supported by the underlying bus or some kind of location information. The format of the string is bus-specific.

instantiate  In object-oriented programming, to create an instance of a class.

instrumentation  A mechanism for reporting information about the state of PC hardware and software to enable management applications to ascertain and change the state of a PC and to be notified of state changes.

integrated device  Any device--such as a parallel port, graphics adapter, and so on--that is designed on the system board rather than on an expansion card.

IntelliMirror"!  Windows 2000-based set of management technologies that provides the best of centralized computing with the best of distributed computing by "intelligently mirroring" system data and applications on the server. Part of the Zero Administration initiative for Windows.

interactive video  A video program and a computer program running in tandem under the control of the user. In interactive video, the user's actions, choices, and decisions genuinely affect the way in which the program unfolds.

interframe coding  Compression techniques that track the differences between frames of video. This results in more compression over a range of frames than intraframe coding.

interlaced  (1) A scanning method that divides the screen into two fields, alternately drawing odd-numbered and even-numbered scan lines. (2) A scheme to display a video image by displaying alternate scan lines in two discrete fields. Interlaced signals are used in broadcast video and are required for video to be compliant with NTSC.

interpolation  The process of averaging pixel information when scaling an image. When reducing the size of an image, pixels are averaged to create a single new pixel; when an image is scaled up in size, additional pixels are created by averaging pixels of the smaller image.

Intranet  Contrary to popular belief, this is not simply a misspelling of "Internet". An Intranet is basically an internal or private Internet used strictly within the confines of a company, university, etc. If you care for a little etymology, "inter" is a prefix meaning "between or among," and "intra" means "within". Hence,the difference between the Internet and an Intranet. Today, using basic Internet technology, intranets have made internal communication much easier. Intranets use a TCP/IP connection, just like the average home Internet user does. The documents in an Intranet are also HTML-based, which is what allows them to be accessed using a web browsers.

I/O  Input/output. Two of the three activities that characterize a computer (input, processing, and output). Refers to the complementary tasks of gathering data for the microprocessor to work with and making the results available to the user through a device such as the display, disk drive, or printer.

IOCTL  Input/output control. A custom class of IRPs available to user mode. Each WDM class driver has a set of IOCTLs that it uses to communicate with applications. The IOCTLs give the class driver information about intended usage by applications. The class driver performs all IOCTL parameter validation.

IP sands for "Internet Protocol." This is what allows for data to be transferred between systems over the Internet. People often say "IP" when referring to an IP address.

IP Address Also known as an IP number. It is a code made up of numbers separated by 4 dots that identifies a particular computer on the Internet. Every computer, whether it be a web server or the computer you're using right now, requires an IP address to be connected to the Internet. For example, the IP address of everyone's favorite computer resource, Sharpened.net, is 216.147.47.134. If you have a standard dial-up account with an Internet Service Provider, you will either be assigned a static IP address (which is always the same), or, as in most cases, you will be given a dynamic IP address

IPL  Initial program load. A device used by the system during the boot process to load an operating system into memory.

IRP  I/O request packet. Data structures that drivers use to communicate with each other. The basic method of communication between kernel-mode devices. An IRP is a key data structure for WDM, which features multiple layered drivers.

IRP_MJ_XXX  IRP Major. One of a predefined class of IRPs that a device can accept.

IRQ  Interrupt request. A method by which a device can request to be serviced by the device's software driver. The system board uses a PIC to monitor the priority of the requests from all devices. When a request occurs, a microprocessor suspends the current operation and gives control to the device driver associated with the interrupt.

ISA  Industry Standard Architecture. An 8-bit (and later, a 16-bit) expansion bus that provides a buffered interface from devices on expansion cards to the PC internal bus.

ISDN  Integrated Service Digital Network. A set of communications standards that enable a single phone line or optical cable to carry voice, digital network services, and video.

isolation  The Plug and Play process by which cards on an ISA bus are distinguished from each other after system startup.

ISO/OSI  International Standards Organization Open Systems Interconnection model. A layered architecture that standardizes levels of service and types of interaction for computers exchanging information through a communications network.

ISP Internet Service Provider. Companies that give you access to the Internet for a monthly fee. ISP's give you a local phone number to call to connect to their computers that are connected to the Internet. When you sign up with an ISP you should receive a username and password to access their computer. In addition, you'll typically get a free email account.

ISR  Interrupt service routine. A routine whose function is to service a device when it generates an interrupt.

J

JavaScript  A programming language designed by Sun Microsystems in conjunction with Netscape which can be integrated into standard HTML pages. It is based off the Java programming language, but is used mainly to create interactive web pages. Because of the usefulness of JavaScript, many professional web sites incorporate it in the HTML of their web pages to make them more dynamic and interactive.

JPEG  Joint Photographic Experts Group. A working committee under the guidance of the ISO that is attempting to define a proposed universal standard for the digital compression and decompression of still images for use in computer systems.

K

Kbps  Stands for "Kilobits Per Second." Try not to confuse this with Kilobytes per second (which is 8 times more data per second). This term is most often used in describing modem speeds. For example, two common modem speeds are 33.6 Kbps and 56 Kbps.

kernel  The core of the layered architecture that manages the most basic operations of the operating system, such as sharing the processor between different blocks of executing code, handling hardware exceptions, and other hardware-dependent functions.

Kilobyte A kilobyte consists of 1024 bytes of computer data. (This is because 2^10 = 1024).  because 1024 is so close to 1000, in most cases a kilobyte is rounded off to1000 bytes.

L

LAN  Local area network. A group of computers and other devices dispersed over a relatively limited area and connected by a communications link that enables any device to interact with any other device on the network. Compare with WAN.

LCD  Stands for "Liquid-Crystal Display." LCDs are very thin displays, which are used for laptop computer screens and flat screen monitors (as well as handheld TVs and video game devices). The image on an LCD screen is created by sandwiching an electrically reactive substance between two electrodes. By increasing or reducing current, LCDs can be lightened or darkened. Since LCDs are based on the principle of blocking light (rather than emitting it), they use up much less power than a cathode-ray tube (CRT) monitor.

legacy  Any feature in the PC system based on older technology for which compatibility continues to be maintained in other system components.

Link  When you're browsing the Web and you see highlighted and underlined words or phrases on a page, there's a good chance you're looking at a link. These friendly little guys allow you to "jump" to another web site, another frame, or another part of the page you're currently viewing.

List Server (Listserv)  A software program used to set up and maintain discussion groups. Many Listserv discussion groups are gateways to Usenet newsgroups as well.

local bus  Usually refers to a system bus directly connected to the microprocessor on a system board. Used colloquially to refer to system board buses located closer to the microprocessor than are ordinary expansion buses (that is, with less buffering), which are therefore capable of greater throughput.

long filename (LFN)  Any filename that exceeds 8.3 characters in length or contains any lowercase characters or any characters that are not valid in the 8.3 namespace. For every long filename, an alias entry is generated that complies with the 8.3 filename rules for backward compatibility.

lossless compression  Ensures that the original data is exactly recoverable with no loss in image quality.

lossy compression  The original data is not completely recoverable. Although image quality may suffer, many experts believe that up to 95 percent of the data in a typical image may be discarded without a noticeable loss in apparent resolution.

LPT device  See parallel (LPT) device.

LRU  Least-recently used. Algorithm for paging.

luminance  Used to describe the black-and-white component of a video signal. The amount of luminance contained in a video signal is directly related to the amount of light intensity. Also, brightness; one of the three image characteristics coded in composite television (represented by the letter Y). See YUV.

M

master clock  Controls the rate of reference time within a graph and is used by filters within the graph to synchronize presentation times. Provides a standard mechanism to query the reference time, to query the physical clock time and rate (compared to the system clock) of the owner of the master clock, and to establish event notifications based on position changes in the master clock's reference time.

MCD  Miniclient driver. An OpenGL driver model in which the driver is responsible only for handling those features that can be accelerated in hardware, leveraging software implementation to handle the rest of the pipeline.

MDL  Memory descriptor list. In Windows NT® and Windows 2000, an opaque structure, defined by Memory Manager, that uses an array of physical page frame numbers to describe the pages that back a virtual memory range.

Megabyte (MB)  actually contains1,048,576 bytes (1,024 x 1,024). This is because 2^10 equals 1024 and not 1000

Megahertz  A Megahertz is 1 million complete cycles per second and is used to measure transmission speeds of electronic devices. The most common area you'll see Megahertz used is in measuring processor speed (like a 500Mhz PentiumIII). However, this only measures the clock speed of the computer's microprocessor - not the overall speed.

Metatag An HTML tag that gives information about a Web page. There are many different types of metatags that perform many tasks, but the most common ensure that the Web page can be found by search engines.

Microprocessor  This little chip is the heart of a computer. The microprocessor, often referred to as just the processor, does all the computations like adding, subtracting, multiplying, dividing, duplicating, etc. In PCs, the most popular microprocessor used is the Intel Pentium, whereas Apple Macintosh computers use the PowerPC chip (developed by Motorola, IBM, and Apple). Microprocessors perform many operations using instructions that are integrated into each chip, but software programs can tell the processor to do specific instructions as well.  Megahertz are used to measure the clock speed of microprocessors but higher Megahertz doesn't always mean faster speeds. Though a 600-MHz chip has a clock speed that is twice as fast as a 300-Mhz chip, it doesn't mean the computer with the 600-Mhz chip will run all tasks twice as fast. This is because the speed of a computer is also influenced by other factors, such as the amount of memory available, the design of the program you're running, and most importantly, the efficiency of the processor. Some processors can complete more operations per clock cycle, making them more efficient that other processors with higher clock speeds.

MIDI  Musical Instrument Digital Interface. An industry-standard connection for computer control of musical instruments and devices. A hardware and data standard for communicating between hardware. Most references involve only the data standard, which is a byte stream used for controlling musical instruments and storing the output of such instruments.

MIPS  Millions of instructions per second. A common measure of processor speed.

mixer class  The class of filters that deal with manipulating controls such as volume, treble, and so on.

monolithic driver  A driver that has many different classes of functionality contained in the same driver.

motherboard  See system board.

MPEG  Moving Pictures Experts Group. Used when referring to one of several standard video-compression schemes. A codec for squeezing full-screen, VHS-quality digital video into a small data stream so it can be played from a CD-ROM drive.  The MPEG organization, which works with the International Oganization for Standardization (ISO), develops standards for digital audio and video compression. The group constantly works to develop more efficient ways to digitally compress and store audio and video files. The term also refers to an actual type of multimedia file. (After all, these guys deserve some credit for what they do...) MPEG files, which typically end with ".mpg," are compressed movies that can contain both audio and video. Though they are compressed (using the compression algorithms created by the Moving Picture Experts Group), they still maintain a high amount of quality from the original, uncompressed movie.

MTD  Memory technology driver. A protected-mode driver that works with Windows protected-mode PC Card software to enable form-factor cards, such as flash memory cards. Such memory cards and their related drivers do not provide full Plug and Play capabilities.

multifunction device  A piece of hardware that supports multiple, discrete functions, such as audio, mixer, and music, on a single adapter.

multimedia  Refers to the delivery of information that combines different content formats (motion video, audio, still images, graphics, animation, text, and so forth).

multimedia processing driver  See filters.

music class  The class of filters that deal with music data, such as ZIPI or MIDI.

N

NDIS  Network Driver Interface Specification. The interface for network drivers used in Windows and Windows NT operating systems. NDIS provides a common mechanism by which any given NDIS-compatible transport driver can communicate with any NDIS-compatible network adapter driver. Moreover, it provides for multiple transports to work over multiple network adapters by supporting multiplexing between transports and drivers.

Net PC  Network PC. A PC designed to meet the industry specification for Network PC systems, which optimizes PC design for flexibility and manageability in order to reduce the total cost of ownership.

Network  When you have two or more computers connected to each other, you have a network. The purpose of a network is to enable the sharing of files and information between mulitple systems. The Internet is a commonly described as a "network of networks."

Newsgroups Also called usenets, they are groups that often have nothing to do with the news. Newsgroups are ongoing discussion forums among people on the Internet who share a mutual interest. Also known as BBS.

NIC  Stands for "Network Interface Card." Pronounced "nick", theses cards are what physically connect a computer to a network cable. 10 Base-T, 100 Base-T, and 10/100 Base-T Ethernet cards are the most common type of NICs. They come in ISA and PCI versions and are made by companies like 3Com (really expensive) and LinkSys (way better priced).

nibble mode  An asynchronous, peripheral-to-host channel defined in the IEEE 1284-1944 standard. Provides a channel for the peripheral to send data to the host, which is commonly used as a means of identifying the peripheral.

NMI  Nonmaskable Interrupt. An interrupt that cannot be overruled by another service request. A hardware interrupt is called nonmaskable if it cannot be masked by the processor interrupt flag.

non-interlaced  The method of scanning all lines on a display from top to bottom in sequential order at a specific rate per second. Unlike television, which uses an interlaced scanning method, computers typically use non-interlaced monitors.

NTFS  Windows NT file system. An advanced file system designed for use specifically with the Windows NT and Windows 2000 operating systems. NTFS supports file system recovery and extremely large storage media, in addition to other advantages.

NTSC  National Television System Committee of the Electronics Industries Association (EIA). The standards-setting body for television and video in the United States. Sponsor of the NTSC standard for encoding color, a coding system compatible with black-and-white signals and the first system used for color broadcasting in the United States. The broadcast standard for the United States and Japan. See also PAL format and SECAM.

NTSC format  A color-television format having 525 scan lines, a field frequency of 60 Hz, a broadcast bandwidth of 4 MHz, line frequency of 15.75 KHz, frame frequency of 1/30 of a second, and a color subcarrier frequency of 3.58 MHz. See also PAL format and SECAM.

O

OCR  Stands for "Optical Character Recognition." Simply put, this is what allows you to scan that paper you printed out, but lost on your hard drive, back into your computer. When a page of text is scanned into a computer, at first, all the computer sees is a bunch graphical bits. In other words, it has no idea that there's text on the page, much less what the text says. However, an OCR program can convert the characters on the page into a text document. It usually isn't a perfect translation, but the newer OCR programs are very accurate. The better ones can even keep the formatting of the document in the translation.

OLE  Object linking and embedding. A way to transfer and share information among applications. OLE is based on the COM programming model and binary standard.

OnNow  A design initiative that seeks to create all the components required for a comprehensive, system-wide approach to system and device power control. OnNow is a term for a PC that is always on but appears off and that responds immediately to user or other requests.

OpenGL  An operating system-independent, industry-standard API for 3-D color graphics programming. Typically used for engineering, visualization, simulation, and other graphics-intensive applications.

Operating System  Also known as an "OS", this is the software that actually communicates with computer's hardware. Without an operating system, all software programs would be useless. The OS is what allocates memory, processes tasks, accesses disks and peripherials, and acts as the user interface. With an operating system, like the Mac OS or Windows 98, developers can write to a common set of programming interfaces (known as APIs) using the operating system to talk the hardware. Without an operating system, programmers would have to write about ten times as much code to get the same results.

option ROM  Optional read-only memory found on an expansion card. Option ROMs usually contain additional firmware required to properly boot the peripheral connected to the expansion card, for example, a hard drive. Also expansion ROM.

OR  A logical operation for combining two bits or two Boolean values; if one or both values are true, it returns the values of true. Compare with XOR.

OSPM  Operating system directed power management. A model of power (and system) management in which the operating system plays a central role and uses global information to optimize system behavior for the task at hand.

out  In terms of data flow in kernel streaming and DirectShow, indicates production of data. An out pin is compatible with an in pin.

Overlay Mixer  The Overlay Mixer filter provides video port playback support. The filter negotiates the parameters that control the video port with an upstream proxy filter that controls the video port driver. It then renders the video on the screen. It can also mix the video content with closed captions on a second pin, and can be extended to an arbitrary number of pins to add subpicture data and other video components.

P

Packet  A small amount of computer data sent over a network. Any time you receive data from the Internet, it comes to your computer in the form of packets. Each packet contains the address of its origin and destination, and information that allows it to "connect" to related packets being sent. The process of sending and receiving packets is known as "packet-switching". Packets from many different locations can be sent on the same lines and be sorted and directed to different routes by various computers along the way.

packed-pixel frame buffer  A portion of the display memory that holds the contents of a single screen image with screen bits stored in a single plane and with each pixel on the screen having a set of two or more corresponding bits that define the pixel color.

PAL format  Phase Alternation Line format. The European video standard, except for France. See also NTSC and SECAM.

Parallel Port This is the interface on the back of a PC used for connecting external devices such as a printer or a scanner. It uses a 25-pin connector (DB-25) and has relatively high bandwidth. The parallel port is sometimes called a Centronics interface, since Centronics was the company that designed the original standard for parallel communication. It is also sometimes referred to as a printer port because the printer is the device most commonly attached to the parallel port. A newer type of parallel port, which supports the same connectors as the Centronics interface, is the Enhanced Parallel Port (EPP) which supports bi-directional communication and can transfer data up to ten times faster than the original Centronics port. However, since the parallel port technology is rather old, don't be surprised to see USB or Firewire interfaces completely replace parallel ports in the future.

parallel (LPT) device  A string of up to 20 characters concatenated from MFG, CMD, MDL, CLS, DES, and CID fields, as defined in the Plug and Play Parallel Port Devices Specification, v. 1.0b.

PC Card  A trademark of PCMCIA. A removable device that is designed to be plugged into a PCMCIA slot and used as a memory-related peri