0-9 A B C D E F G H I J K L M N O P Q R S T U V W XYZ

PREVIOUS PAGE         Return to ANSDIT

early binding:
A characteristic of programming languages that perform most bindings during translation, usually to achieve execution efficiency. For example, COBOL, Fortran, Pascal.

eavesdropping:
The unauthorized interception of information-bearing emanations.

EBCDIC:
extended binary-coded decimal interchange code.

e-business:
A business that conducts its affairs substantially using electronic commerce.

e-cash:
Synonym for electronic cash.

echo:
The immediate notification of the current values provided by an input unit to the user at the display console.

e-commerce:
Synonym for electronic commerce.

edge:
The limit of a defined region such as in an image where the region is defined by a given color or brightness. Contrast with boundary.

edge-based stereo:
The stereographic technique based on matching edges in views of the same scene taken from different positions.

edge detection:
An image-segmentation technique in which edge pixels are identified by examining their neighborhoods.

edge enhancement:
An image-enhancement technique in which edges are sharpened by increasing the contrast between the pixel values of the edge pixels.

edge following:
An image-segmentation algorithm for isolating a region by following edges.

edge-lit display:
A display that uses a light source or light sources from the periphery.

edge pixel:
A pixel that lies at the limit of a defined region.

EDI:
electronic data interchange, electronic document interchange.

edit:
To prepare or manipulate data for a specific purpose. Editing may include the rearrangement, the addition or modification of data, the deletion of unwanted data, format control, code conversion, or text editing, and the application of standard processes such as zero suppression.

editing:
Synonym for text editing.

EEPROM:
electrically erasable programmable read-only memory.

effective address:
The address that results from performing any required indexing, indirect addressing, or other address modification on a specified address. If the specified address requires no address modification, it is also the effective address.

effective transfer rate:
(1) The average number of bits, characters, or blocks transferred per unit of time between two points and accepted as valid at the reception. (2) The actual number of units of user data (e.g., bits or bytes) that are transferred per unit of time.

efficiency:
A measure of how well a program or functional unit makes use of available resources, such as storage space and processor speed.

EIDE:
enhanced integrated drive electronics.

EISA (Extended Industry Standard Architecture):
A microcomputer bus standard that supports 32-bit data exchange as an extension to the 16-bit ISA architecture.

EIT:
encoded information type.

EITHER-OR operation:
Deprecated synonym for disjunction.

elaboration:
The process by which a declaration achieves its effect prior to execution, such as resolution of references, data type checking, or storage allocation. (Figure 58 - State transition diagram).

elapsed time:
The span of time actually elapsed from the beginning to the end of the execution of a program. Contrast with processor time.

electrically erasable programmable read-only memory (EEPROM):
A PROM that can be erased by electric pulses and reused.

electrocutaneous feedback:
A method of tactile communication for displaying machine information to human operators, which is delivered in pulses of low-voltage electricity applied to external electrodes on the skin of the operator.

electroluminescent display:
A display in which luminescence resulting from electrical excitation of a phosphor on a thin film is used.

electronic archive:
A collection of documents in storage for historical or backup purposes; for example, a stored collection of various versions of a document.

electronic cash:
Data representing money and transferred by means of a computer network. Electronic cash is traded as a token which can be exchanged for real money. Synonymous with e-cash, digital cash.

electronic commerce:
Commerce in which transactions are performed via computer networks in real-time. Example: Online shopping, where people can order goods via a computer network, for instance, by means of a network browser. Synonymous with e-commerce.

electronic copresence:
The total involvement of a participant in a virtual world through a feeling of "being there". Synonymous with copresence, virtual copresence.

electronic data interchange:
Synonym for electronic document interchange.

electronic document interchange (EDI):
The exchange of data and documents between computer systems according to standard rules. Synonymous with electronic data interchange.

electronic magazine:
Synonym for e-zine.

electronic mail:
Correspondence in the form of messages, and possibly attachments, transmitted between user terminals over a computer network. Synonymous with email, e-mail. Spelling variations of the synonyms are E mail, E-mail, Email.

electronic mailbox:
Synonym for mailbox.

electronic messaging:
The creation, transfer, storing, and retrieval of messages by electronic means.

electronic publishing:
The distribution of publications by electronic means as distinct from using physical media, such as paper; for example, distribution of a weekly newsletter through the use of international electronic mail and making the newsletter available as a page on the World Wide Web so that subscribers may access it using a browser.

electronic shutter glasses:
The stereoscopic glasses with shutters that are synchronized with computer-generated images to produce the sensation of three-dimensional images. Synonymous with shutter goggles.

electronic vision:
Synonym for computer vision.

electrostatic plotter:
A raster plotter that creates an electrostatic latent display image, that is then made visible, transferred, and fixed on paper.

electrostatic printer:
A nonimpact printer that creates an electrostatic latent image, which is then made visible by a toner and transferred and fixed on output medium.

electrostatic storage:
A storage device that uses electrically charged areas on a dielectric surface layer.

elementary statement:
Deprecated synonym for simple statement.

elevator:
In computer graphics, a movable area on a vertical scroll bar that shows the relative position of the data or display image currently displayed in a window. Synonymous with slider box.

elongation:
A measure of shape features equal to the length of the major axis divided by the length of the minor axis. Circles have an elongation factor of 1; elongated objects have a value greater than 1. In some cases axes may be difficult to define.

EM:
The end-of-medium character.

e-mail:
Synonym for electronic mail.

email:
Synonym for electronic mail.

embedded command:
In text processing, a command, entered as part of the text, that is interpreted when a document is formatted for print preview, for creation of a print file, or when the document is printed.

embedded database language:
A language for manipulating databases, added to a conventional programming language; for example, embedded SQL in COBOL.

embedded system:
A computational system that is a part of a larger system whose primary purpose is not computational; for example, a computer in a satellite or process control system.

embodiment:
The sense of bodily presence in a virtual world combined with a great plasticity of bodily representation.

emergency plan:
Synonym for contingency plan.

emission security:
Protection against compromising emanations.

emoticon:
A composite symbol using characters to represent the mood of the originator; for example: common emoticons include:
   :–)   means happy,
   :–(   means sad.
Loosely called smiley.

empty medium:
A data medium that contains only marks of reference but no user data.

emulate:
To imitate a system so that the imitating system accepts the same data, executes the same programs, and achieves the same results as the imitated system.

emulation:
The use of a data processing system to imitate some other system, so that the imitating system accepts the same data, executes the same programs, and achieves the same results as the imitated system. Emulation may be achieved by means of hardware or firmware but may be entirely software on a general purpose computer.

emulator:
Hardware, software, microprograms, or any combination thereof, that enables one data processing system to emulate another.

enabling signal:
A signal that permits the occurrence of an event.

encapsulate:
To control access to the implementation details of a language construct by requiring use of predefined interfaces. Encapsulation is one tool to implement information hiding.

encapsulated type:
A data type with publicly defined interfaces and privately defined implementation of the internal structure and the associated operations.

encapsulation:
The process or the result of encapsulating.

encipher:
In computer security, to convert plaintext into an unintelligible form by means of a cipher system.

encipherment:
Synonym for encryption.

encode:
To convert data by the use of a code in such a manner that reconversion to the original form is possible. Synonymous with code.

encoded information type (EIT):
In data communications, an identification of the type of encoded data of individual parts of the content. This identifier may be in the envelope or in the content and may indicate syntax and coding such as MIME (Multipurpose Internet Mail Extender), or ASN.1 (Abstract Syntax Notation 1, an ISO/ITU-T standard).

encrypt:
To encode or to encipher.

encryption:
The cryptographic transformation of data. The result of encryption is ciphertext. The reverse process is called decryption. Synonymous with encipherment.

end-around borrow:
The action of transferring a borrow digit from the most significant digit place to the least significant digit place.

end-around carry:
The action of transferring a carry digit from the most significant digit place to the least significant digit place; for example, an end-around carry may be necessary when adding two negative numbers that are represented by their diminished radix complements.

end-around shift:
Synonym for circular shift.

end node:
A node that is the end point of a path; for example, a terminal in a computer network. End nodes may correspond to extremes of a network or may be intermediate nodes that represent extreme points of a subnetwork. Synonymous with endpoint node.

end-of-file label:
An internal label that indicates the end of a file and that may contain data for use in file control. An end-of-file label may include control totals for comparison with counts accumulated during processing. Synonymous with trailer label.

end-of-frame:
A specified bit pattern or a specified signal that indicates the end of a frame. Synonymous with frame end delimiter. (Figure 27 - Frame in data communication).

end-of-medium character (EM):
A control character that may be used to identify the physical end of the data medium, the end of the used portion of the data medium, or the end of the wanted portion of the data recorded on the data medium.

end-of-tape marker:
A marker on a magnetic tape used to indicate the end of the permissible recording area; for example, a photoreflective strip, a transparent section of tape.

end-of-text character (ETX):
A transmission control character used to terminate text.

end-of-transmission-block character (ETB):
A transmission control character used to indicate the end of a transmission block of data when data are divided into such transmission blocks for transmission purposes.

end-of-transmission character (EOT):
A transmission control character used to indicate the conclusion of a transmission which may have included one or more texts and any associated message headings.

end-of-volume label:
An internal label that indicates the end of the data contained in a volume.

endpoint node:
Synonym for end node.

end-to-end encryption:
The protection of information passed in a communication system by cryptographic means, from point of origin to point of destination.

end user:
The person who benefits, directly or indirectly, from the capabilities of a computer system and uses these capabilities to perform a task.

end-user language:
A language employed by end users for defining information processing.

enhanced integrated drive electronics (EIDE):
A type of enhanced interface between a computer and a disk drive for standalone personal computers.

ENQ:
The enquiry character.

enquiry character (ENQ):
A transmission control character used as a request for a response from the station with which the connection has been set up; the response may include station identification, the type of equipment in service, and the status of the remote station.

enrollment:
Speech training of a speaker-dependent system using training samples from a given speaker.

entity:
(1) Anything, such as a person, place, process, object, concept, association, or event. (2) In databases, any concrete or abstract thing that exists, did exist, or might exist, including associations among these things. For example, a person, object, event, idea, process, etc. An entity exists whether data about it are available or not. (3) In OSI, an element within a subsystem.

entity class:
A set of entities with common attributes. For example, "Sales transaction" or "employee."

entity identification:
A method of using one or more attributes whose attribute values uniquely identify each occurrence of a specified entity.

entity instance:
Synonym for entity occurrence.

entity-integrity property:
In a relation, the property that precludes a null value for any primary key or component of a primary key.

entity occurrence:
A specific entity of a given entity type. For example, a particular sales transaction or a particular employee. Synonymous with entity instance.

entity relationship:
A perceived association among entities or among attributes of the same entity class. In certain contexts, an entity relationship may be considered to be an entity.

entity-relationship data model:
A data model based on the concept of entities, entity relationships among entities, and of the attributes of entities and relationships.

entity set:
A collection of entities that have the same attribute types.

entity type:
The specification of a class of entities, including identification of attributes and operations.

entity world:
A collection of entities that are related to a particular aspect of a universe of discourse. For example, "Payroll" and "sales accounts" could be perceived as entity worlds in the universe of discourse "all financial aspects of an organization."

entrance:
Synonym for entry point.

entrance surface:
The surface of an optical disk onto which the optical beam first impinges.

entrapment:
In computer security, the deliberate planting of apparent flaws in a data processing system for the purpose of detecting attempted penetrations or for confusing an intruder about which flaws to exploit.

entropy:
The mean value of the information content of the events in a finite set of mutually exclusive and jointly exhaustive events; that is in mathematical notation:
n
n
H(X)  =
p(xi) I(xi)  =
p(xi) log [1 / p(xi)]
i = 1
i = 1
where: X = {x1...xn} is the set of events xi (i=1 ...n), I(xi) are the information contents of the events xi and p(xi) the probabilities of the occurrences of these events, subject to
n
p(xi) = 1
i = 1
Example: Let X={a,b,c} be a set of three events and let p(a) = 0.5, p(b) = 0.25, and p(c) = 0.25 be the probabilities of their occurrences. The entropy of this set is:
H(X) = p(a) I(a) + p(b) I(b) + p(c) I(c) = 1.5 Sh
Synonymous with average information content.

entry:
The initiation of an execution sequence at the beginning of a subprogram or elsewhere as designated by an entry name in the subprogram.

entry name:
An identifier that designates the beginning of an execution sequence.

entry call statement:
A simple statement that permits a task to request a rendezvous with another task.

entry point:
(1) A point in a program, module, or statement at which execution of this program, module, or statement can begin. Synonymous with entrance. (2) In the context of databases, the record that is first accessed upon entry into a database, caused by a user's command.

enumerated type:
Synonym for enumeration type.

enumeration literal:
A literal that is an instance of an enumeration type.

enumeration type:
A data type whose values are explicitly enumerated in the declaration of such a data type. Synonymous with enumerated type.

envelope:
Synonym for header (in email).

environment:
(1) A collection of hardware resources and software resources that supports one or more phases of software development or use of software. (2) The state of a computer and its operating system during the execution of a program.

environmental condition:
A physical condition required for the protection and proper operation of a functional unit. Examples are temperature, humidity, vibration, dust, and radiation. An environmental condition is usually specified as a nominal value and a tolerance range. For a device, there may be more than one set of environmental conditions; for example, one set for transport, another for storage, and another for operation.

EOF:
end-of-file.

EOT:
The end-of-transmission character.

EOV:
end-of-volume.

episode:
Synonym for scene.

EPLD:
erasable programmable logic device.

epoch:
In artificial intelligence, a sequence of training patterns introduced into an artificial neural network.

EPROM (erasable programmable read-only memory):
A PROM that can be erased by a special process and reused. The special process is typically an exposure to ultraviolet radiation.

equals function:
The function that allows the completion of a series of operations and the provision of the result.

equivalence:
A logic operation where the result is True if and only if the truth value of each of the operands is identical. Truth values are frequently represented by 1 or 0 as in Boolean operations.

equivalence gate:
A gate that performs the Boolean operation of equivalence. For Boolean variables assuming values of 0 or 1, an if-and-only-if gate outputs a value 1 if and only if its two input values are the same; otherwise it outputs a value 0. Synonymous with XNOR gate.

equivalence operation:
In Boolean algebra, the operation whose result has the Boolean value 1 if and only if the operands have the same Boolean value. Synonymous with IF-AND-ONLY-IF operation, identity operation. (Figure 4 - Table of Boolean operations).

equivalent-binary digit factor:
The average number of bits required to express one radix digit in a nonbinary numeration system; for example, approximately three times as many digits are required to express a binary numeral as to express the equivalent decimal numeral.

equivocation:
The conditional entropy of a specific set of messages at a message source given a specific set of messages at a message sink which is connected to the message source by a specific channel. The equivocation is the mean additional information content that must be supplied per message at the message sink to correct the received messages affected by a noisy channel.

Next Page