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MICROSOFT Computer Dictionary, Fifth Edition

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Microsoft Computer Dictionary, Fifth Edition

n. See exterior gateway protocol.

e-home

n. See smart home.

EIA

n. Acronym for Electronic Industries Association. An association based in Washington, D.C., with members from various electronics manufacturers. It sets standards for electronic components. RS-232-C, for example, is the EIA standard for connecting serial components. See also RS-232- C standard.

EIDE or E-IDE

n. Acronym for Enhanced Integrated Drive Electronics. An extension of the IDE standard, EIDE is a hardware interface standard for disk drive designs that house control circuits in the drives themselves. It allows for standardized interfaces to the system bus while providing for advanced features, such as burst data transfer and direct data access. EIDE accommodates drives as large as 8.4 gigabytes (IDE supports up to 528 megabytes). It supports the ATA-2 interface, which permits transfer rates up to 13.3 megabytes per second (IDE permits up to 3.3 megabytes per second), and the ATAPI interface, which connects drives for CD-ROMs, optical discs and tapes, and multiple channels. Most PCs have EIDE drives, which are cheaper than SCSI drives and provide much of the same functionality. See also IDE, SCSI.

Eiffel

n. An advanced object-oriented programming language with a syntax similar to C, developed by Bertrand Meyer in 1988. Eiffel runs on MS-DOS, OS/2, and UNIX. Its major design features are the ability to use modules in multiple programs and software extensibility.

Eiffel#

n. Pronounced “Eiffel Sharp.” A subset language of Eiffel specifically designed to target the .NET Framework and embody the full extent of Design by Contract. See also Design by Contract.

eight dot three n. See 8.3.

EIP

n. See enterprise information portal.

EIS

n. See executive information system.

EISA

n. Acronym for Extended Industry Standard Architecture. A bus standard for the connection of add-on cards to a PC motherboard, such as video cards, internal modems, sound cards, drive controllers, and cards that support other peripherals. EISA was introduced in 1988 by a consortium of nine computer industry companies. The companies—AST Research, Compaq, Epson, Hewlett-Packard, NEC, Olivetti, Tandy, Wyse, and Zenith—were referred to collectively as “the Gang of Nine.” EISA maintains compatibility with the earlier Industry Standard Architecture (ISA) but provides for additional features introduced by IBM in its Micro Channel Architecture bus standard. EISA has a 32-bit data path, and it uses connectors that can accept ISA cards. However, EISA cards are compatible only with EISA systems. EISA can operate at much higher frequencies than the ISA bus and provides much faster data throughput than ISA. See also ISA, Micro Channel Architecture.

EJB

n. See Enterprise JavaBeans.

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electroluminescent

adj. Giving off light when electric current is applied. Electroluminescent panels are used in portable computers to backlight the liquid crystal displays. A thin phosphor layer is sandwiched between two thin electrode panels, one of which is nearly transparent. See also liquid crystal display.

electroluminescent display

n. A type of flat-panel display used in laptops in which a thin phosphor layer is set between vertical and horizontal electrodes. These electrodes form xy-coordinates; when a vertical and a horizontal electrode are charged, the phosphor at their intersection emits light. Electroluminescent displays provide a sharp, clear image and a wide viewing angle. They were replaced by active matrix LCD screens. See also flat-panel display, liquid crystal display, passivematrix display. Compare active-matrix display.

electrolysis

n. A process in which a chemical compound is broken down into its constituent parts by passing an electric current through it.

electromagnet

n. A device that creates a magnetic field when electric current passes through it. An electromagnet typically contains an iron or steel core with wire wrapped around it. Current is passed through the wire, producing a magnetic field. Electromagnets are used in disk drives to record data onto the disk surface.

electromagnetic radiation

n. The propagation of a magnetic field through space. Radio waves, light, and X rays are examples of electromagnetic radiation, all traveling at the speed of light.

electromagnetic spectrum

n. The range of frequencies of electromagnetic radiation. In theory, the spectrum’s range is infinite. See the illustration.

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Electromagnetic spectrum.

electromotive force

n. The force that causes movement in charge carriers (the electrons) in a conductor. Acronym: EMF. Also called: potential, voltage. See also ampere, coulomb.

electron beam

n. A stream of electrons moving in one direction. An electron beam is used in a cathode-ray tube (CRT) to produce an image as it is passed across the phosphor coating inside the tube. See also CRT.

electron gun

n. A device that produces an electron beam, typically found in television or computer monitors. See also CRT.

electronic bulletin board n. See BBS (definition 1).

electronic cash n. See e-money.

electronic circuit n. See circuit.

electronic commerce n. See e-commerce.

Electronic Commerce Modeling Language

n. A computer language developed by leading e-commerce companies as a standard for inputting e-wallet information into the payment fields of Web sites. This allows for one-click transfer of e- wallet information at compatible Web sites. Acronym: ECML.

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electronic credit

n. A form of electronic commerce involving credit card transactions carried out over the Internet. Also called: e-credit. See also e-commerce.

electronic data interchange n. See EDI.

electronic data processing n. See data processing.

electronic form n. See e-form.

Electronic Frontier Foundation

n. A public advocacy organization dedicated to the defense of civil liberties for computer users. The organization was founded in 1990 by Mitchell Kapor and John Perry Barlow as a response to U.S. Secret Service raids on hackers. Acronym: EFF.

electronic funds transfer

n. The transfer of money via automated teller machine, telephone lines, or Internet connection. Examples of electronic fund transfers include using a credit card to make purchases from an e- commerce site, or using an automated teller machine or automated telephone banking system to move funds between bank accounts. Acronym: EFT.

Electronic Industries Association n. See EIA.

electronic journal n. See journal.

electronic mail n. See e-mail1.

electronic mail services

n. Services that allow users, administrators, or daemons to send, receive, and process e-mail. See also daemon.

electronic mall

n. A virtual collection of online businesses that affiliate with the intention of increasing the exposure of each business through the fellow businesses.

electronic money n. See e-money.

electronic music

n. Music created with computers and electronic devices. See also MIDI, synthesizer.

electronic office

n. A term used especially in the late 1970s to mid-1980s to refer to a hypothetical paperless work environment to be brought about by the use of computers and communications devices.

electronic paper

n. Technology allowing a computer display to imitate the look and feel of traditional paper media. Electronic paper consists of thin, flexible sheets of plastic containing millions of small beads called microcapsules. Each microcapsule contains both a black and a white pigment and displays

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the proper color in response to an electrical charge. It retains this pattern until a new screen of text or images is requested.

electronic photography

n. See digital photography.

Electronic Privacy Information Center n. See EPIC.

electronic publishing

n. A general term for distributing information via electronic media, such as communications networks or CD-ROM.

electronics

n. The branch of physics dealing with electrons, electronic devices, and electrical circuits.

Electronics Industries Association n. See EIA.

electronic software distribution

n. A means of directly distributing software to users on line over the Internet. Electronic software distribution is analogous to direct-mail ordering. Acronym: ESD.

electronic spreadsheet

n. See spreadsheet program.

electronic storefront

n. A business that displays its merchandise on the Internet and has provisions for contact or online sales.

electronic text n. See e-text.

electron tube

n. A device for switching and amplifying electronic signals. It consists of a sealed glass container with electronic elements, such as metallic plates and grids, inside. In most applications, tubes have been replaced by transistors, although they are still used in cathode-ray tubes and in some radio frequency circuits and audio amplifiers. Also called: vacuum tube, valve. See also CRT.

electrophotographic printers

n. Printers in a category including laser, LED, LCD, and ion-deposition printers. In such a printer, a negative image is applied to an electrically charged, photosensitive drum. A photosensitive drum develops a pattern of electrostatic charge on its surface representing the photo negative of the image the drum will print. Powdered ink (toner) adheres to the charged areas of the drum, the drum presses the ink onto the paper, and then heat binds the toner to the paper. The printer types vary mainly in how they charge the drum. See also ion-deposition printer, laser printer, LCD printer, LED printer.

electrophotography

n. The production of photographic images using electrostatic charges. This method is used in photocopiers and laser printers. Also called: xerography. See also electrophotographic printers.

electroplating

n. The use of electrolysis for depositing a thin layer of one material onto another material. See also electrolysis.

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electrostatic

adj. Of or relating to electric charges that are not flowing along a conducting path. Electrostatic charges are used in copiers and laser printers to hold toner particles on a photoconducting drum and in flatbed plotters to hold the plot medium in place.

electrostatic discharge

n. The discharge of static electricity from an outside source, such as human hands, into an integrated circuit, often resulting in damage to the circuit. Acronym: ESD.

electrostatic plotter

n. A plotter that creates an image from a dot pattern on specially coated paper. The paper is electrostatically charged and exposed to toner, which adheres to the dots. Electrostatic plotters can be up to 50 times faster than pen plotters but are more costly. Color models produce images through multiple passes with cyan, magenta, yellow, and black. See also plotter. Compare electrophotographic printers, pen plotter.

electrostatic printer

n. See electrostatic plotter.

elegant

adj. Combining simplicity, terseness, efficiency, and subtlety. On the academic side of computer science, elegant design (say, of programs, algorithms, or hardware) is a priority, but in the frenetic pace of the computer industry, elegant design may be sacrificed for the sake of speeding a product’s development, sometimes resulting in bugs that are difficult to correct.

element

n. 1. Any stand-alone item within a broader context. For example, a data element is an item of data with the characteristics or properties of a larger set; a picture element (pixel) is one single dot on a computer screen or in a computer graphic; a print element is the part of a daisy-wheel printer that contains the embossed characters. See also daisy-wheel printer, data element, graphics primitive, pixel, thimble. 2. In markup languages such as HTML and SGML, the combination of a set of tags, any content contained between the tags, and any attributes the tags may have. Elements can be nested, one within the other. See also attribute (definition 3), HTML, markup language, SGML.

elevator

n. The square box within a scroll bar that can be moved up and down to change the position of text or an image on the screen. See the illustration. Also called: scroll box, thumb. See also scroll bar.

Elevator.

elevator seeking

n. A method of limiting hard disk access time in which multiple requests for data are prioritized based on the location of the data relative to the read/ write head. This serves to minimize head movement. See also access time (definition 2), hard disk, read/write head.

elite

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n. 1. A size of fixed-width type that prints 12 characters to the inch. 2. A fixed-width font that may be available in various type sizes. See also monospace font.

ELIZA

n. A program, modeled on Rogerian psychotherapy, that conducts simulated conversations with humans by echoing responses and posing questions based on key words in earlier comments. It was created by Dr. Joseph Weizenbaum, who considered it a bit of a joke and was alarmed that people took it seriously. See also artificial intelligence, Turing test.

ellipsis

n. A set of three dots (...) used to convey incompleteness. In many windowing applications, selection of a command that is followed by an ellipsis will produce a submenu or a dialog box. In programming and software manuals, an ellipsis in a syntax line indicates the repetition of certain elements. See also dialog box, syntax.

elm

n. Short for electronic mail. A program for reading and composing e-mail on UNIX systems. The elm program has a full-screen editor, making it easier to use than the original mail program, but elm has largely been superseded by pine. See also e-mail1. Compare Eudora, pine.

e-mail1 or email or E-mail

n. 1. Short for electronic mail. The exchange of text messages and computer files over a communications network, such as a local area network or the Internet, usually between computers or terminals. 2. An electronic text message.

e-mail2 or email or E-mail

vb. To send an e-mail message.

e-mail address

n. A string that identifies a user so that the user can receive Internet e-mail. An e-mail address typically consists of a name that identifies the user to the mail server, followed by an at sign (@) and the host name and domain name of the mail server. For example, if Anne E. Oldhacker has an account on the machine called baz at Foo Enterprises, she might have an e-mail address aeo@baz.foo.com, which would be pronounced “A E O at baz dot foo dot com.”

e-mail filter

n. A feature in e-mail-reading software that automatically sorts incoming mail into different folders or mailboxes based on information contained in the message. For example, all incoming mail from a user’s Uncle Joe might be placed in a folder labeled “Uncle Joe.” Filters may also be used either to block or accept e-mail from designated sources.

e-mail management system

n. An automated e-mail response system used by an Internet-based business to sort incoming e- mail messages into predetermined categories and either reply to the sender with an appropriate response or direct the e-mail to a customer service representative. Acronym: EMS.

embed

vb. To insert information created in one program, such as a chart or an equation, into another program. After the object is embedded, the information becomes part of the document. Any changes made to the object are reflected in the document.

embedded

adj. In software, pertaining to code or a command that is built into its carrier. For example, application programs insert embedded printing commands into a document to control printing and formatting. Low-level assembly language is embedded in higher-level languages, such as C, to provide more capabilities or better efficiency.

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embedded chip

n. See embedded system.

embedded command

n. A command placed in a text, graphics, or other document file, often used for printing or pagelayout instructions. Such commands often do not appear on screen but can be displayed if needed. In transferring documents from one program to another, embedded commands can cause problems if the programs are incompatible.

embedded controller

n. A processor-based controller circuit board that is built into the computer machinery. See also controller.

embedded hyperlink

n. A link to a resource that is embedded within text or is associated with an image or an image map. See also hyperlink, image map.

embedded interface

n. An interface built into a hardware device’s drive and controller board so that the device can be directly connected to the computer’s system bus. See also controller, interface (definition 3). Compare ESDI, SCSI, ST506 interface.

embedded system

n. Microprocessors used to control devices such as appliances, automobiles, and machines used in business and manufacturing. An embedded system is created to manage a limited number of specific tasks within a larger device or system. An embedded system is often built onto a single chip or board and is used to control or monitor the host device—usually with little or no human intervention and often in real time. See also microprocessor.

em dash

n. A punctuation mark (—) used to indicate a break or interruption in a sentence. It is named for the em, a typographical unit of measure that in some fonts equals the width of a capital M. Compare en dash, hyphen.

EMF

n. See electromotive force.

emitter

n. In transistors, the region that serves as a source of charge carriers. Compare base (definition 3), collector.

emitter-coupled logic

n. A circuit design in which the emitters of two transistors are connected to a resistor so that only one of the transistors switches at a time. The advantage of this design is very high switching speed. Its drawbacks are the high number of components required and susceptibility to noise. Acronym: ECL.

EMM

n. See Expanded Memory Manager.

e-money or emoney

n. Short for electronic money. A generic name for the exchange of money through the Internet. Also called: cybercash, digicash, digital cash, e-cash, e-currency.

emotag

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n. In an e-mail message or newsgroup article, a letter, word, or phrase that is encased in angle brackets and that, like an emoticon, indicates the attitude the writer takes toward what he or she has written. Often emotags have opening and closing tags, similar to HTML tags, that enclose a phrase or one or more sentences. For example: <joke>You didn’t think there would really be a joke here, did you?</joke>. Some emotags consist of a single tag, such as <grin>. See also emoticon, HTML.

emoticon

n. A string of text characters that, when viewed sideways, form a face expressing a particular emotion. An emoticon is often used in an e-mail message or newsgroup post as a comment on the text that precedes it. Common emoticons include :-) or :) (meaning “I’m smiling at the joke here”), ;-) (“I’m winking and grinning at the joke here”), :-( (“I’m sad about this”), :-7 (“I’m speaking with tongue in cheek”), :D or :-D (big smile; “I’m overjoyed”), and :-O (either a yawn of boredom or a mouth open in amazement). Compare emotag.

EMS

n. Acronym for Expanded Memory Specification. A technique for adding memory to PCs that allows for increasing memory beyond the Intel 80x86 microprocessor real-mode limit of 1 megabyte (MB). In earlier versions of microprocessors, EMS bypassed this memory board limit with a number of 16-kilobyte banks of RAM that could be accessed by software. In later versions of Intel microprocessors, including the 80386 and 80486 models, EMS is converted from extended memory by software memory managers, such as EMM386 in MS-DOS 5. Now EMS is used mainly for older MS-DOS applications because Windows and other applications running in protected mode on 80386 and higher microprocessors are free of the 1-MB limit. Also called: LIM EMS. See also expanded memory, protected mode. Compare conventional memory, extended memory.

em space

n. A typographical unit of measure that is equal in width to the point size of a particular font. For many fonts, this is equal to the width of a capital M, from which the em space takes its name. Compare en space, fixed space, thin space.

emulate

vb. For a hardware or software system to behave in the same manner as another hardware or software system. In a network, for example, microcomputers might emulate terminals in order to communicate with mainframes.

emulation

n. The process of a computer, device, or program imitating the function of another computer, device, or program.

emulator

n. Hardware or software designed to make one type of computer or component act as if it were another. By means of an emulator, a computer can run software written for another machine. In a network, microcomputers might emulate terminals in order to communicate with mainframes.

emulsion laser storage

n. A method for recording data in film by selective heating with a laser beam.

enable

vb. To activate or turn on. Compare disable.

encapsulate

vb. 1. To treat a collection of structured information as a whole without affecting or taking notice of its internal structure. In communications, a message or packet constructed according to one protocol, such as a TCP/IP packet, may be taken with its formatting data as an undifferentiated

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stream of bits that is then broken up and packaged according to a lower-level protocol (for example, as ATM packets) to be sent over a particular network; at the destination, the lower-level packets are assembled, re-creating the message as formatted for the encapsulated protocol. See also ATM (definition 1). 2. In object-oriented programming, to keep the implementation details of a class a separate file whose contents do not need to be known by a programmer using that class. See also object-oriented programming, TCP/IP.

Encapsulated PostScript n. See EPS.

encapsulated type

n. See abstract data type.

encapsulation

n. 1. In object-oriented programming, the packaging of attributes (properties) and functionality (methods or behaviors) to create an object that is essentially a “black box”—one whose internal structure remains private and whose services can be accessed by other objects only through messages passed via a clearly defined interface (the programming equivalent of a mailbox or telephone line). Encapsulation ensures that the object providing service can prevent other objects from manipulating its data or procedures directly, and it enables the object requesting service to ignore the details of how that service is provided. See also information hiding. 2. In terms of the Year 2000 problem, a method of dealing with dates that entails shifting either program logic (data encapsulation) or input (program encapsulation) backward into the past, to a parallel year that allows the system to avoid Year 2000 complications. Encapsulation thus allows processing to take place in a “time warp” created by shifting to an earlier time before processing and—for accuracy—shifting output forward by the same number of years to reflect the actual date. See data encapsulation, program encapsulation.

encipher

vb. See encrypt.

encode

vb. 1. See encrypt. 2. In programming, to put something into code, which frequently involves changing the form—for example, changing a decimal number to binary-coded form. See also binary-coded decimal, EBCDIC.

encoder

n. 1. In general, any hardware or software that encodes information—that is, converts the information to a particular form or format. For example, the Windows Media Encoder converts audio and video to a form that can be streamed to clients over a network. 2. In reference to MP3 digital audio in particular, technology that converts a WAV audio file into an MP3 file. An MP3 encoder compresses a sound file to a much smaller size, about one-twelfth as large as the original, without a perceptible drop in quality. Also called: MP3 encoder. See also MP3, WAV. Compare rip, ripper.

encoding

n. 1. See Huffman coding. 2. A method of dealing with computers with Year 2000 problems that entails storing a four-digit year in date fields designed to hold only two digits in a program or system. This can be accomplished by using the bits associated with the date field more efficiently—for example, by converting the date field from ASCII to binary or from decimal to hexadecimal, both of which allow storage of larger values.

encrypt

vb. To encode (scramble) information in such a way that it is unreadable to all but those individuals possessing the key to the code. Encrypted information is known as cipher text. Also called: encipher, encode.

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