Software Engineering Glossary

Software Engineering Glossary

"A" Glossary Content

Press the "Letter" button to view the glossary contents for that specific letter.

Other topics within the glossary:

abend	Abbreviation for abnormal end.
ability to perform	See: common features.
abnormal end (abend)	Termination of a process prior to completion. See also: abort; exception.
abort	To terminate a process prior to completion.
absolute address	An address that is permanently assigned to a device or storage location and that identifies the device or location without the need for translation or calculation. Syn: explicit address; specific address. Contrast with: relative address; relocatable address; symbolic address. See also: absolute assembler; absolute code; absolute instruction; absolute loader.
absolute assembler	An assembler that produces absolute code. Contrast with: relocating assembler.
absolute code	Code in which all addresses are absolute addresses. Syn: specific code. Contrast with: relocatable code.
absolute instruction	A computer instruction in which all addresses are absolute addresses. See also: direct instructions; effective instruction; immediate instruction; indirect instruction.
absolute loader	A loader that reads absolute machine code into main memory, beginning at the initial address assigned to the code by the assembler or compiler, and performs no address adjustments on the code. Contrast with: relocating loader.
abstract data type	A data type for which only the properties of the data and the operations to be performed on the data are specific, without concern for how the data will be represented or how the operations will be implemented.
abstraction	A view of a problem that extracts the essential information relevant to a particular purpose and ignores the remainder of the information. The process of forming an abstraction.
acceptance criteria	The criteria a system or component must satisfy in order to be accepted by a user, customer, or other authorized entity. See also: requirement; test criteria.
acceptance testing	Formal testing conducted to determine whether or not a system satisfies its acceptance criteria and to enable the customer to determine whether or not to accept the system. Formal testing conducted to enable a user, customer, or other authorized entity to determine whether to accept a system or component. Contrast with: development testing. See also: operational testing; qualification testing.
accuracy	A qualitative assessment of correctness, or freedom from error. A quantitative measure of the magnitude of error. Contrast with: precision.
action item	A unit in a list that has been assigned to an individual or group for disposition. An action proposal that has been accepted.
action proposal	A documented suggestion for change to a process or process-related item that will prevent the future occurrence of defects identified as a result of defect prevention activities. (See also software process improvement proposal. )
active	The window or icon that you are currently using or that is currently selected. The next keystroke or command you choose always applies to the active window or icon. If a window is active, its title bar changes color to differentiate it from other windows, and if an icon is active, its label changes color. (Unless you have specified otherwise in Control Panel.) Windows or icons on the desktop that are not selected are inactive.
active redundancy	In fault tolerance, the use of redundant elements operating simultaneously to prevent, or permit recovery from failures. Contrast with: standby redundancy.
activities performed	See: common features.
activity	Any step taken or function performed, both mental and physical, toward achieving some objective. Activities include all the work the managers and technical staff do to perform the tasks of the project and organization. (See task for contrast.)
actual parameter	See: argument (3).
adaptability	See: flexibility.
adaptation data	Data used to adapt a program to a given installation site or to given conditions in its operational environment.
adaptation parameter	A variable that is given a specific value to adapt a program to a given installation site or to given conditions in its operational environment; for example, the variable Installation_Site_Latitude.
adaptive maintenance	Software maintenance performed to make a computer program usable in a changed environment. Contrast with: corrective maintenance; perfective maintenance.
address	A number, character, or group of characters that identifies a given device or storage location. To refer to a device or storage location by an identifying number, character, or group of characters. See also: absolute address; effective address; implied addressing; indirect address; relative address; relocatable address; symbolic address; virtual address.
address field	Any of the fields of a computer instruction that contain addresses, information necessary to derive addresses, or values of operands. Syn: address part. Contrast with: operation field.
address format	The number and arrangement of address fields in a computer instruction. See also: n-address instruction; n-plus-one address instruction. The number and arrangement of elements within an address, such as the elements needed to identify a particular channel, device, disk sector, and record in magnetic disk storage.
address modification	Any arithmetic, logical, or syntactic operation performed on an address. See also: effective address; indexed address; relative address; relocatable address.
address part	See: address field
address space	The addresses that a computer program can access. Note: In some systems, this may be the set of physical storage location that a program can access, disjoint from other programs, together with the set of virtual addresses referring to those storage locations, which may be accessible by other programs. The number of memory locations that a central processing unit can address.
addressing exception	An exception that occurs when a program calculates an address outside the bounds of the storage available to it. See also: data exception; operation exception; overflow exception; protection exception; underflow exception.
afferent	Pertaining to a flow of data or control from a subordinate module to a superordinate module in a software system. Contrast with: efferent.
algebraic language	A programming language that permits the construction of statements resembling algebraic expressions, such as Y = X + 5. For example, FORTRAN. See also: algorithmic language; list processing language; logic programming language.
algorithm	A finite set of welldefined rules for the solution of a problem in a finite number of steps; for example, a complete specification of a sequence of arithmetic operations for evaluating sin x to a given precision. Any sequence of operations for performing a specific task.
algorithm analysis	The examination of an algorithm to determine its correctness with respect to its intended use, to determine its operation characteristics, or to understand it more fully in order to modify, simplify, or improve it.
algorithmic language	A programming language designed for expressing algorithms; for example, ALGOL. See also: algebraic language; list processing language; logic programming language.
alias	An additional name for an item. An alternate label. For example, a label and one or more aliases may be used to refer to the same data element or point in a computer program.
allocated baseline	In configuration management, the initial approved specifications governing the development of configuration items that are part of a higher level configuration item. Contrast with: developmental configuration; functional baseline; product baseline. See also: allocated configuration identification.
allocated configuration identification	In configuration management, the current approved specifications governing the development of configuration items that are part of a higher level configuration item. Each specification defines the functional characteristics that are allocated from those of the higher level configuration item, establishes the test required to demonstrate achievement of its allocated functional characteristics, delineates necessary interface requirements with other associated configuration items, and establishes design constraints, if any. Contrast with: functional configuration identification; product configuration identification. See also: allocated baseline.
allocated requirements	See: system requirements allocated to software.
allocation	The process of distributing requirements, resources, or other entities among the components of a system or program. The result of the distribution in (1).
analysis phase	See: requirements phase.
analytical model	A representation of a process or phenomenon by a set of solvable equations. Contrast with: simulation.
annotation	A note or comment that you add to a Help topic. You can add comments to a Help topic by using the Annotate command on the Edit menu.
anomaly	Anything observed in the documentation or operation of software that deviates from expectations based on previously verified software products or reference documents.
anticipatory buffering	A buffering technique in which data are stored in a buffer in anticipation of a need for the data. See also: dynamic buffering; simple buffering.
anticipatory paging	A storage allocation technique in which pages are transferred from auxiliary storage to main storage in anticipation of a need for those pages. Contrast with: demand page.
application	A computer program used for a particular kind of work, such as word processing. This term is often used interchangeably with "program."
application domain	A bounded set of related systems (i.e., systems that address a particular type of problem). Development and maintenance in an application domain usually requires special skills and/or resources. Examples include payroll and personnel systems, command and control systems, compilers, and expert systems.
application software	Software designed to fulfill specific needs of a user: for example, software for navigation, payroll, or process control. Contrast with: support software; system software.
application window	The main window for an application, which contains the application menu bar and workspace. An application window may contain multiple document windows.
application-oriented language	A computer-oriented language with facilities or notations applicable primarily to a single application area; for example, a language for computer-assisted instruction or hardware design. See also: authoring language; specification language; query language.
architectural design	The process of defining a collection of hardware and software components and their interfaces to establish a framework for the development of a computer system. See also: functional design. The result of the process in (1).
architecture	The organizational structure of a system or component. See also: component; module; subprogram routine.
argument	An independent variable; for example, the variable m in the equation E = mc2. A specific value of an independent variable; for example, the value of m = 24 kg. A constant, variable, or expression used in a call to a software module to specify data or program elements to be passed to the module. Syn: actual parameter. Contrast with: formal parameter.
array	An n-dimensional ordered set of data items identified by a single name and one or more indices, sot that each element of the set is individually addressable. For example, a matrix, table, or vector.
arrow keys	The keys on your computer keyboard that you use to navigate around your screen. Each key is named for the direction the arrow points. There is an UP ARROW, DOWN ARROW, LEFT ARROW, and RIGHT ARROW key.
artificial language	See: formal language.
assemble	To translate a program expressed in an assembly language into its machine language equivalent. Contrast with: compile; disassemble; interpret.
assemble-and-go	An operating technique in which there are no stops between the assembling, linking, loading, and execution of a computer program.
assembler	A computer program that translates programs express in assemble language into their machine language equivalents. See also: absolute assembler; cross-assembler; relocating, assembler. Contrast with: compiler; interpreter.
assembler code	See: assembly code.
assembler language	See: assembly language.
assembly code	Computer instructions and data definitions expressed in a form that can be recognized and processed by an assembler. Syn: assembler code. Contrast with: compiler code; interpretive code; machine code.
assembly language	A programming language that corresponds closely to the instruction set of a given computer, allows symbolic naming of operations and addresses, and usually results in a on-to-one translation of program instructions into machine instructions. Syn: assembler language; low level language; second generation language. Contrast with: fifth generation language; fourth generation language; high order language; machine language.
assertion	A logical expression specifying a program state that must exist or a set of conditions that program variables must satisfy at a particular point during program execution. Types include input assertion, loop assertion, output assertion. See also: invariant; proof of correctness.
assessment	See: software process assessment.
assignment statement	A computer program statement that assigns a value to a variable; for example, Y := X - 5. Contrast with: control statement; declaration. See also: clear; initialize; reset.
associate	To identify a filename extension as "belonging" to a certain application. When you open a file having that extension, the application starts automatically.
atomic type	A data type, each of whose member consist of a single, nondecomposable data item. Syn: primitive type. Contrast with: composite type.
attribute	A characteristic of an item; for example, the item's color, size, or type. See also: quality attribute.
attributes	Information that indicates whether a file is a read-only, hidden, or system file, and whether the file has been changed since a backup copy of it was made.
audit	An independent examination of a work product or set of work products to assess compliance with specifications, standards, contractual agreements, or other criteria. See also: functional configuration audit; physical configuration audit.
authoring language	A high level programming language used to develop courseware for computer-assisted instruction. See also: authoring system.
authoring system	A programming system that incorporates an authoring language.
automated verification system	A software tool that accepts as input a computer program and a representation of its specification, and produces, possibly with human help, a proof or disproof of the correctness of the program. Any software tool that automate part or all of the verification process.
availability	The degree to which a system or component is operational and accessible when required for use. Often expressed as a probability. See also: error tolerance; fault tolerance; robustness.