Software Engineering Glossary

Software Engineering Glossary

"O" Glossary Content

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object	Pertaining to the outcome of an assembly or compilation process. See also: object code; object module; object program. A program constant or variable. Any piece of information, created by using a Windows-based application, that can be linked to or embedded in another document. An encapsulation of data and services that manipulate that data. See also: object-oriented design.
object code	Computer instructions and data definitions in a form output by an assembler or compiler. An object program is made up of object code. Contrast with: source code.
object language	See: target language.
object linking and embedding	A way to transfer and share information between applications.
object module	A computer program or subprogram that is the output of an assembler or compiler. See also: load module; object program.
object program	A computer program that is the output of an assembler or compiler. Syn: target program. Contrast with: source program. See also: object module.
object-oriented design	A software development technique in which a system or component is expressed in terms of objects and connections between those objects. See also: data structure-centered design; input-process-output; modular decomposition; rapid prototyping; stepwise refinement; structured design; transaction analysis; transform analysis.
object-oriented language	A programming language that allows the user to express a program in terms of objects and messages between those objects. Examples include Smalltalk, C++, and Java.
occupational title standard	A standard that describes the characteristics of the general areas of work or profession
off-line	Pertaining to a device or process that is not under the direct control of the central processing unit of a computer. Contrast with: on-line (2).
offset	The difference between the loaded origin and the assembled origin of a computer program. Syn: relocation factor. A number that must be added to a relative address to determine the address of the storage location to be accessed. This number may be the difference defined in (1) or another number defined in the program. See also: base address; indexed address; relative address; self-relative address.
on-line	Pertaining to a system or mode of operation in which input data enter the computer directly from the point of origin or output data are transmitted directly to the point where they are used. For example, an airline reservation system. Contrast with: batch. See also: conversational; interactive; real time. Pertaining to a device or process that is under the direct control of the central processing unit of a computer. Contrast with: off-line.
on-line compiler	See: incremental compiler.
one-address instruction	A computer instruction that contains one address field. For example, an instruction to load the contents of location A. Syn: single-address instruction; single-operand instruction. Contrast with: multiaddress instruction; two-address instruction; three-address instruction; four-address instruction; zero address instruction.
one-ahead addressing	A method of implied addressing in which the operands for a computer instruction are understood to be in the storage locations following the locations of the operands used for the last instruction executed. Contrast with: repetitive addressing.
one-level address	See: direct address.
one-plus-one address instruction	A computer instruction that contains two address fields, the second containing the address of the instruction to be executed next. For example, an instruction to load the contents of location A, then execute the instruction at location B. Contrast with: two-plus-one address instruction; three-plus-one address instruction; four-plus-one address instruction.
op code (opcode)	See: operation code.
open	To display the contents of a directory, a document, or a data file in a window.
open subroutine	A subroutine that is copied into a computer program at each place that it is called. Syn: direct insert subroutine. Contrast with: closed subroutine. See also: inline code; macro.
operand	A variable, constant, or function upon which an operation is to be performed. For example, in the expression A = B + 3, B and 3 are the operands.
operating system	A collection of software, firmware, and hardware elements that controls the execution of computer programs and provides such services as computer resource allocation, job control, control, and file management in a computer system.
operation	In computer mathematics, the action specified by an operator on one or more operands. For example, in the expression A = B + 3, the process of adding B to 3 to obtain A. In programming, a defined action that can be performed by a computer system; for example, addition, comparison, branching. Note: Unlike the mathematical meaning, such an operation may not involve an operator or operands; for example, the operation Halt. The process of running a computer system in its intended environment to Perform its intended functions.
operation and maintenance phase	The period of time in the software life cycle during which a software product is employed in its operational environment, monitored for satisfactory performance, and modified as necessary to correct problems or to respond to changing requirements.
operation code	A character or set of characters that specifies a computer operation; for example, the code BNZ to designate the operation "branch if not zero." Syn: op code.
operation exception	An exception that occurs when a program encounters an invalid operation code. See also: addressing exception; data exception; overflow exception; protection exception; underflow exception.
operation field	The field of a computer instruction that specifies the operation to be performed. Syn: function field; operation part. Contrast with: address field.
operation part	See: operation field.
operational	Pertaining to a system or component that is ready for use in its intended environment. Pertaining to a system or component that is installed in its intended environment. Pertaining to the environment in which a system or component is intended to be used
operational software	The software that is intended to be used and operated in a system when it is delivered to its customer and deployed in its intended environment.
operational testing	Testing conducted to evaluate a system or component in its operational environment. Contrast with: development testing. See also: acceptance testing; qualification testing.
operator	A mathematical or logical symbol that represents an action to be performed in an operation. For example, in the expression A = B + 3, + is the operator, representing addition. A person who operates a computer system.
operator field	See: operation field.
operator manual	A document that provides the information necessary to initiate and operate a system or component. Typically described are procedures for preparation, operation, monitoring, and recovery. Note: An operator manual is distinguished from a user manual when a distinction is made between those who operate a computer system (mounting tapes, etc.) and those who use the system for its intended purpose. See also: diagnostic manual; installation manual; programmer manual; support manual; user manual.
optimizing level	See: maturity level.
option button	A small, round button that appears in a dialog box. Within a group of related option buttons, you can select only one button.
order clash	In software design, a type of structure clash in which a program must deal with two or more data sets that have been sorted in different orders. See also: data structure-centered design.
organization	A unit within a company or other entity (e.g., government agency or branch of service) within which many projects are managed as a whole. All projects within an organization share a common top-level manager and common policies.
organizations measurement program	The set of related elements for addressing an organization's measurement needs. It includes the definition of organization-wide measurements, methods and practices for collecting organizational measurement data, methods and practices for analyzing organizational measurement data, and measurement goals for the organization.
organizations software process assets	A collection of entities, maintained by an organization, for use by projects in developing, tailoring, maintaining, and implementing their software processes. These software process assets typically include: the organization's standard software process, descriptions of the software life cycles approved for use, the guidelines and criteria for tailoring the organization's standard software process, the organization's software process database, and a library of software process-related documentation. Any entity that the organization considers useful in performing the activities of process definition and maintenance could be included as a process asset.
organizations software process database	A database established to collect and make available data on the software processes and resulting software work products, particularly as they relate to the organization's standard software process. The database contains or references both the actual measurement data and the related information needed to understand the measurement data and assess it for reasonableness and applicability. Examples of process and work product data include estimates of software size, effort, and cost; actual data on software size, effort, and cost; productivity data; peer review coverage and efficiency; and number and severity of defects found in the software code.
organization's standard software process	The operational definition of the basic process that guides the establishment of a common software process across the software projects in an organization. It describes the fundamental software process elements that each software project is expected to incorporate into its defined software process. It also describes the relationships (e.g., ordering and interfaces) between these software process elements.
orientation	An overview or introduction to a topic for those overseeing or interfacing with the individuals responsible for performing in the topic area. Contrast with: train.
origin	The address of the initial storage location assigned to a computer program in main memory. See also: assembled origin; loaded origin. Contrast with: starting address.
output	Pertaining to data transmitted to an external destination. Pertaining to a device, process, or channel involved in transmitting data to an external destination. To transmit data to an external destination. Loosely, output data. Contrast with: input.
output assertion	A logical expression specifying one or more conditions that program outputs must satisfy in order for the program to be correct. Contrast with: input assertion; loop assertion. See also: inductive assertion method.
overflow exception	An exception that occurs when the result of an arithmetic operation exceeds the size of the storage location designated to receive it. See also: addressing exception; data exception; operation exception; exception; underflow exception.
overhead operation	See: housekeeping operation.
overhead time	The amount of time a computer system spends performing tasks that do not contribute directly to the progress of any user task; for example, time spent tabulating computer resource usage for billing purposes.
overlay	A storage allocation technique in which computer program segments are loaded from auxiliary storage to main storage when needed, overwriting other segments not currently in use. A computer program segment that is maintained in auxiliary storage and loaded into main storage when needed, overwriting other segments not currently in use. To load a computer program segment from auxiliary storage to main storage in such a way that other segments of the program are overwritten.
overlay supervisor	A routine that controls the sequencing and positioning of overlays.
overload	To assign an operator, identifier, or literal more than one meaning, depending upon the data types associated with it at any given time during program execution