Data Science: Classifier (Definitions)

[pattern classifier:] "A neural net to determine whether an input pattern is or is not a member of a particular class. Training data consists of input patterns and the class to which each belongs, but does not require a description of each class; the net forms exemplar vectors for each class as it learns the training patterns." (Laurene V Fausett, "Fundamentals of Neural Networks: Architectures, Algorithms, and Applications", 1994)

[Bayes classifier:] "statistical classification algorithm in which the class borders are determined decision-theoretically, on the basis of class distributions and misclassification costs." (Teuvo Kohonen, "Self-Organizing Maps" 3rd Ed., 2001)

[nonparametric classifier:] "classification method that is not based on any mathematical functional form for the description of class regions, but directly refers to the available exemplary data." (Teuvo Kohonen, "Self-Organizing Maps" 3rd Ed., 2001)

[parametric classifier:] "classification method in which the class regions are defined by specified mathematical functions involving free parameters." (Teuvo Kohonen, "Self-Organizing Maps" 3rd Ed., 2001)

"A set of patterns and rules to assign a class to new examples." (Ching W Wang, "New Ensemble Machine Learning Method for Classification and Prediction on Gene Expression Data", 2008)

"A structured model that maps unlabeled instances to finite set of classes." (Lior Rokach, "Incorporating Fuzzy Logic in Data Mining Tasks", Encyclopedia of Artificial Intelligence, 2009)

"A decision-supporting system that given an unseen (to-be-classified) input object yields a prediction, for instance, it classifies the given object to a certain class." (Ivan Bruha, "Knowledge Combination vs. Meta-Learning", 2009)

"Algorithm that produces class labels as output, from a set of features of an object. A classifier, for example, is used to classify certain features extracted from a face image and provide a label (an identity of the individual)." (Oscar D Suárez & Gloria B García, "Component Analysis in Artificial Vision" Encyclopedia of Artificial Intelligence, 2009)

"An algorithm to assign unknown object samples to their respective classes. The decision is made according to the classification feature vectors describing the object in question." (Michael Haefner, "Pit Pattern Classification Using Multichannel Features and Multiclassification", 2009)

"function that associates a class c to each input pattern x of interest. A classifier can be directly constructed from a set of pattern examples with their respective classes, or indirectly from a statistical model." (Óscar Pérez & Manuel Sánchez-Montañés, Class Prediction in Test Sets with Shifted Distributions, 2009)

[Naive Bayes classifier:] "A modeling technique where each attribute describes a class independent of any other attributes that also describe that class." (DAMA International, "The DAMA Dictionary of Data Management", 2011)

"An algorithm that implements classification in the field of machine learning and statistical analysis." (Golnoush Abaei & Ali Selamat, "Important Issues in Software Fault Prediction: A Road Map", 2014)

"A computational method that can be trained using known labeled data for predicting the label of unlabeled data. If there's only two labels (also called classes), the method is called 'detector'." (Addisson Salazar et al, "New Perspectives of Pattern Recognition for Automatic Credit Card Fraud Detection", 2018)

[Naive Bayes classifier:] "A way to classify a data item using Bayes' theorem concerning the conditional probabilities P(A|B)=(P(B|A) * P(A))/P(B). It also assumes that variables in the data are independent, which means that no variable affects the probability of the remaining variables attaining a certain value." (David Natingga, "Data Science Algorithms in a Week" 2nd Ed., 2018)

"A type of machine learning program that segments a set of cases into different classes or categorizations." (Shalin Hai-Jew, "Methods for Analyzing and Leveraging Online Learning Data", 2019)

"A supervised Data Mining algorithm used to categorize an instance into one of the two or more classes." (Mu L Wong & S Senthil "Development of Accurate and Timely Students' Performance Prediction Model Utilizing Heart Rate Data", 2020)

"A model that can be used to place objects into discrete categories based on some set of features. Classifiers are trained on datasets." (Laurel Powell et al, "Art Innovative Systems for Value Tagging", 2021)

Data Management: Data Flow (Definitions)

"The sequence in which data transfer, use, and transformation are performed during the execution of a computer program."  (IEEE," IEEE Standard Glossary of Software Engineering Terminology", 1990)

"A component of a SQL Server Integration Services package that controls the flow of data within the package." (Marilyn Miller-White et al, "MCITP Administrator: Microsoft® SQL Server™ 2005 Optimization and Maintenance 70-444", 2007)

"Activities of a business process may exchange data during the execution of the process. The data flow graph of the process connects activities that exchange data and - in some notations - may also represent which input/output parameters of the activities are involved." (Cesare Pautasso, "Compiling Business Process Models into Executable Code", 2009)

"Data dependency and data movement between process steps to ensure that required data is available to a process step at execution time." (Christoph Bussler, "B2B and EAI with Business Process Management", 2009)

[logical data flow:] "A data flow diagram that describes the flow of information in an enterprise without regard to any mechanisms that might be required to support that flow." (David C Hay, "Data Model Patterns: A Metadata Map", 2010)

[physical data flow:] "A data flow diagram that identifies and represents data flows and processes in terms of the mechanisms currently used to carry them out." (David C Hay, "Data Model Patterns: A Metadata Map", 2010)

"The fact that data, in the form of a virtual entity class, can be sent from a party, position, external entity, or system process to a party, position, external entity, or system process." (David C Hay, "Data Model Patterns: A Metadata Map", 2010)

"An abstract representation of the sequence and possible changes of the state of data objects, where the state of an object is any of: creation, usage, or destruction [Beizer]." (International Qualifications Board for Business Analysis, "Standard glossary of terms used in Software Engineering", 2011)

"Data flow refers to the movement of data from one purpose to another; also the movement of data through a set of systems, or through a set of transformations within one system; it is a nontechnical description of how data is processed. See also Data Chain." (Laura Sebastian-Coleman, "Measuring Data Quality for Ongoing Improvement ", 2012)

"The movement of data through a group of connected elements that extract, transform, and load data." (Microsoft, "SQL Server 2012 Glossary", 2012)

"A path that carries packets of information of known composition; a roadway for data. Every data flow’s composition is recorded in the data dictionary." (James Robertson et al, "Complete Systems Analysis: The Workbook, the Textbook, the Answers", 2013)

"the path, in information systems or otherwise, through which data move during the active phase of a study." (Meredith Zozus, "The Data Book: Collection and Management of Research Data", 2017)

"The lifecycle movement and storage of data assets along business process networks, including creation and collection from external sources, movement within and between internal business units, and departure through disposal, archiving, or as products or other outputs." (Kevin J Sweeney, "Re-Imagining Data Governance", 2018)

"A graphical model that defines activities that extract data from flat files or relational tables, transform the data, and load it into a data warehouse, data mart, or staging table." (Sybase, "Open Server Server-Library/C Reference Manual", 2019)

"An abstract representation of the sequence and possible changes of the state of data objects, where the state of an object is any of: creation, usage, or destruction." (Software Quality Assurance)

Programming: Framework (Definitions)

"Unifying, guiding architectural approach, as in the data warehouse bus architecture." (Ralph Kimball & Margy Ross, "The Data Warehouse Toolkit" 2nd Ed., 2002)

"A collection of classes, functions, protocols, documentation, and header files and other resources that are all related." (Stephen G Kochan, "Programming in Objective-C", 2003)

"A set of collaborating abstract and concrete classes that may be used as a template to solve a related family of problems. It is usually extended via subclassing for application-specific behavior." (Craig Larman, "Applying UML and Patterns", 2004)

"A coherent architecture that provides an incomplete template for systems within a specific domain; a coherent set of design patterns." (Bruce P Douglass, "Real-Time Agility", 2009)

"A support structure for developing software products." (Judith Hurwitz et al, "Service Oriented Architecture For Dummies" 2nd Ed., 2009)

"1.Generally, a basic skeletal structure. 2.Conceptually, a classification scheme used to better understand a topic; a defined and documented paradigm, used as a lens to view a complex problem. 3.In software development, a reusable object-oriented design, including a library of reusable classes and other components, along with standards for designing additional components and how they interact." (DAMA International, "The DAMA Dictionary of Data Management", 2011)

"A support structure for developing and managing software products." (Marcia Kaufman et al, "Big Data For Dummies", 2013)

"A structure for supporting something else." ( Manish Agrawal, "Information Security and IT Risk Management", 2014)

"A support structure for developing and managing software." (Judith S Hurwitz, "Cognitive Computing and Big Data Analytics", 2015)

"A conceptual set of rules and ideas that provide structure to a complex and challenging situation." (Weiss, "Auditing IT Infrastructures for Compliance" 2nd Ed., 2015)

"A framework is a set of concepts that provide the basic structure for understanding a domain, enabling a common vocabulary for different explanatory theories." (Robert J Glushko, "The Discipline of Organizing: Professional Edition" 4th Ed., 2016)

Software Engineering: Classes (Just the Quotes)

"A subsystem is a set of classes (and possibly other subsystems) collaborating to fulfill a set of responsibilities. Although subsystems do not exist as the software executes, they are useful conceptual entities." (Rebecca Wirfs-Brock, "Object-oriented Design: A. responsibility-driven approach", 1989)

"The data-driven approach to object-oriented design focuses on the structure of the data in a system. This results in the incorporation of structural information in the definitions of classes. Doing so violates encapsulation. The responsibility-driven approach emphasizes the encapsulation of both the structure and behavior of objects. By focusing on the contractual responsibilities of a class, the designer is able to postpone implementation considerations until the implementation phase. While responsibility-driven design is not the only technique addressing this problem, most other techniques attempt to enforce encapsulation during the implementation phase. This is too late in the software life-cycle to achieve maximum benefits." (Rebecca Wirfs-Brock, "Object-oriented design: a responsibility-driven approach", 1989)

"In object-oriented analysis, we seek to model the world by identifying the classes and objects that form the vocabulary of the problem domain, and in object-oriented design, we invent the abstractions and mechanisms that provide the behavior that this model requires." (Grady Booch, "Object-Oriented Design: With Applications", 1991) 

"Object-oriented analysis is a method of analysis that examines requirements from the perspective of the classes and objects found in the vocabulary of the problem domain."(Grady Booch, "Object-oriented design: With Applications", 1991)

"Object-oriented programming is a method of implementation in which programs are organized as cooperative collections of objects, each of which represents an instance of some class, and whose classes are all members of a hierarchy of classes united via inheritance relationships." (Grady Booch, "Object-oriented design: With Applications", 1991)

"Whereas object-oriented analysis typically focuses upon one specific problem at a time, domain analysis seeks to identify the classes and objects that are common to all applications within a given domain, such as missile avionics systems, compilers, or accounting software." (Grady Booch, "Object-oriented design: With Applications", 1991)

"Object-oriented methods tend to focus on the lowest-level building block: the class and its objects." (Peter Coad, "Object-oriented patterns", 1992)

"If you're passing a parameter among several routines, that might indicate a need to factor those routines into a class that share the parameter as object data. Streamlining parameter passing isn't a goal, per se, but passing lots of data around suggests that a different class organization might work better." (Steve C McConnell," Code Complete: A Practical Handbook of Software Construction", 1993)

"[...] inheritance is a powerful tool for reducing complexity because a programmer can focus on the generic attributes of an object without worrying about the details. If a programmer must be constantly thinking about semantic differences in subclass implementations, then inheritance is increasing complexity rather than reducing it." (Steve C McConnell," Code Complete: A Practical Handbook of Software Construction", 1993)

"Inheritance is the idea that one class is a specialization of another class. The purpose of inheritance is to create simpler code by defining a base class that specifies common elements of two or more derived classes. The common elements can be routine interfaces, implementations, data members, or data types. Inheritance helps avoid the need to repeat code and data in multiple locations by centralizing it within a base class. When you decide to use inheritance, you have to make several decisions: For each member routine, will the routine be visible to derived classes? Will it have a default implementation? Will the default implementation be overridable? For each data member (including variables, named constants, enumerations, and so on), will the data member be visible to derived classes?" (Steve C McConnell," Code Complete: A Practical Handbook of Software Construction", 1993)

"Modularity's goal is to make each routine or class like a 'black box': You know what goes in, and you know what comes out, but you don't know what happens inside." (Steve C McConnell," Code Complete: A Practical Handbook of Software Construction", 1993)

"Watch for coupling that's too tight. 'Coupling' refers to how tight the connection is between two classes. In general, the looser the connection, the better. Several general guidelines flow from this concept: Minimize accessibility of classes and members. Avoid friend classes, because they're tightly coupled. Make data private rather than protected in a base class to make derived classes less tightly coupled to the base class. Avoid exposing member data in a class's public interface. Be wary of semantic violations of encapsulation. Observe the 'Law of Demeter' [...]. Coupling goes hand in glove with abstraction and encapsulation. Tight coupling occurs when an abstraction is leaky, or when encapsulation is broken." (Steve C McConnell," Code Complete: A Practical Handbook of Software Construction", 1993)

"Often you'll see the same three or four data items together in lots of places: fields in a couple of classes, parameters in many method signatures. Bunches of data that hang around together really ought to be made into their own object." (Kent Beck, "Refactoring: Improving the Design of Existing Code", 1999)

"An object-oriented application is a set of interacting objects. Each object is an implementation of one or more roles. A role supports a set of related (cohesive) responsibilities. A responsibility is an obligation to perform a task or know certain information. And objects don't work in isolation, they collaborate with others in a community to perform the overall responsibilities of the application. So a conceptual view, at least to start, is a distillation of the key object roles and their responsibilities (stated at a fairly high level). More than likely (unless you form classification hierarchies and use inheritance and composition techniques) many candidates you initially model will map directly to a single class in some inheritance hierarchy. But I like to open up possibilities by think first of roles and responsibilities, and then as a second step towards a specification-level view, mapping these candidates to classes and interfaces." (Rebecca Wirfs-Brock, [interview] 2003)

"On small, informal projects, a lot of design is done while the programmer sits at the keyboard. 'Design' might be just writing a class interface in pseudocode before writing the details. It might be drawing diagrams of a few class relationships before coding them. It might be asking another programmer which design pattern seems like a better choice. Regardless of how it’s done, small projects benefit from careful design just as larger projects do, and recognizing design as an explicit activity maximizes the benefit you will receive from it." (Steve C McConnell, "Code Complete: A Practical Handbook of Software Construction" 2nd Ed., 2004)

"An abstraction is not a module, or an interface, class, or method; it is a structure, pure and simple - an idea reduced to its essential form. Since the same idea can be reduced to different forms, abstractions are always, in a sense, inventions, even if the ideas they reduce existed before in the world outside the software. The best abstractions, however, capture their underlying ideas so naturally and convincingly that they seem more like discoveries." (Daniel Jackson, "Software Abstractions", 2006)

"Clean code is focused. Each function, each class, each module exposes a single-minded attitude that remains entirely undistracted, and unpolluted, by the surrounding details."  (Robert C Martin, "Clean Code: A Handbook of Agile Software Craftsmanship", 2008)

"Every system is built from a domain-specific language designed by the programmers to describe that system. Functions are the verbs of that language, and classes are the nouns."  (Robert C Martin, "Clean Code: A Handbook of Agile Software Craftsmanship", 2008)

Software Engineering: Data/Information Hiding (Definitions)

"In programming, the practice of locating some parts of the system in software structures that are invisible (inaccessible) to others. Usually, the information so hidden includes details that the programmer considers inessential and those aspects of the system that result from design decisions that are somehow difficult or likely to change. Compare with abstraction, which is a category of techniques by which one can make decisions about what information to hide." (Bill Pribyl & Steven Feuerstein, "Learning Oracle PL/SQL", 2001)

"Hiding the state of a class in private member variables." (Jesse Liberty, "Sams Teach Yourself C++ in 24 Hours" 3rd Ed., 2001)

"The ability of an object to hide its members from other parts of a program to protect those members from accidental change." (Greg Perry, "Sams Teach Yourself Beginning Programming in 24 Hours" 2nd Ed., 2001)

"The ability of a class to hide the details about how it works from outside code." (Rod Stephens, "Start Here! Fundamentals of Microsoft .NET Programming", 2011)

"The practice of hiding the details of a module with the goal of controlling access to the details of the module" (Nell Dale & John Lewis, "Computer Science Illuminated" 6th Ed., 2015)

"Use of segregation in design decisions to protect software components from negatively interacting with each other. Commonly enforced through strict interfaces." (Adam Gordon, "Official (ISC)2 Guide to the CISSP CBK" 4th Ed., 2015)

"The practice of hiding details within a module with the goal of controlling access to the details from the rest of the system" (Nell Dale et al, "Object-Oriented Data Structures Using Java" 4th Ed., 2016)

"The dependability concept of not allowing functions access to data structures unless they are specifically designated to do so in the context of a module or object." (O Sami Saydjari, "Engineering Trustworthy Systems: Get Cybersecurity Design Right the First Time", 2018)

"Concealing the structure of some (potentially unstable) parts of a program behind a stable interface." (Karl Beecher, "Computational Thinking - A beginner's guide to problem-solving and programming", 2017)

"The intentional denial of access to operate directly on data without going through specified encapsulating procedures, which operate on the data in a well-controlled manner. See encapsulation." (O Sami Saydjari, "Engineering Trustworthy Systems: Get Cybersecurity Design Right the First Time", 2018)

OOP: Attribute (Definitions)

"Additional characteristics or information defined for an entity." (Owen Williams, "MCSE TestPrep: SQL Server 6.5 Design and Implementation", 1998)

"A named characteristic or property of a class." (Craig Larman, "Applying UML and Patterns", 2004)

"A characteristic, quality, or property of an entity class. For example, the properties 'First Name' and 'Last Name' are attributes of entity class 'Person'." (Danette McGilvray, "Executing Data Quality Projects", 2008)

"Another name for a field, used by convention in many object-oriented programming languages. Scala follows Java’s convention of preferring the term field over attribute." (Dean Wampler & Alex Payne, "Programming Scala", 2009)

"1. (UML diagram) A descriptor of a kind of information captured about an object class. 2. (Relational theory) The definition of a descriptor of a relation." (David C Hay, "Data Model Patterns: A Metadata Map", 2010)

"A fact type element (specifically a characteristic assignment) that is a descriptor of an entity class." (David C Hay, "Data Model Patterns: A Metadata Map", 2010)

"A characteristic of an object." (Requirements Engineering Qualifications Board, "Standard glossary of terms used in Requirements Engineering", 2011)

"An inherent characteristic, an accidental quality, an object closely associated with or belonging to a specific person, place, or office; a word ascribing a quality." (DAMA International, "The DAMA Dictionary of Data Management", 2011)

OOP: Generalization (Definitions)

"The activity of identifying commonality among concepts and defining a superclass (general concept) and subclass (specialized concept) relationships. It is a way to construct taxonomic classifications among concepts which are then illustrated in class hierarchies." (Craig Larman, "Applying UML and Patterns: An Introduction to Object-Oriented Analysis and Design and the Unified Process", 1997)

"The activity of identifying commonality among concepts and defining a superclass (general concept) and subclass (specialized concept) relationships. It is a way to construct taxonomic classifications among concepts, which are then illustrated in class hierarchies. Conceptual subclasses conform to conceptual superclasses in terms of intension and extension." (Craig Larman, "Applying UML and Patterns", 2004)

"The process of forming a more comprehensive or less restrictive class (a superclass) from one or more entities (or classes, in Unified Modeling Language [UML])." (Sharon Allen & Evan Terry, "Beginning Relational Data Modeling 2nd Ed.", 2005)

"In extended ER model (EER model), generalization is a structure in which one object generally describes more specialized objects." (S. Sumathi & S. Esakkirajan, "Fundamentals of Relational Database Management Systems", 2007)

"A special type of abstraction relationship that specifies that several types of entities with certain common attributes can be generalized (or abstractly defined) with a higher-level entity type, a supertype entity; an 'is-a' type relationship. For example, employee is a generalization of engineer, manager, and administrative assistant, based on the common attribute job-title. A tool often used to make view integration possible." (Toby J Teorey, ", Database Modeling and Design" 4th Ed., 2010)

"In a specialization hierarchy, the grouping together of common attributes into a supertype entity. See specialization hierarchy." (Carlos Coronel et al, "Database Systems: Design, Implementation, and Management 9th Ed", 2011)

"The process of evaluating multiple relationships between entities in a set into fewer relationships. Usually necessary after other generalization activities have taken place, which carry the relationships of the specialized entities into the generalized entities. For example, two 1:M relationships between two entities, each having a different parent, can be generalized into a M:N relationship." (DAMA International, "The DAMA Dictionary of Data Management", 2011)

"The process of recognizing commonalities, and combining similar types of entities or objects into a less specialized type based on common attributes and behaviors, creating a supertype for two or more specialized subtypes. Contrast with specialization." (DAMA International, "The DAMA Dictionary of Data Management", 2011)

"The abstraction, reduction, and simplification of features and feature classes for deriving a simpler model of reality or decreasing stored." (GRC Data Intelligence)

OOP: Method (Definitions)

"A function that performs an action by using a component object model (COM) object, as in SQL-DMO, OLE DB, and ADO." (Microsoft Corporation, "SQL Server 7.0 System Administration Training Kit", 1999)

"A programmatic operation such as a procedure or function defined on an object type or class." (Bill Pribyl & Steven Feuerstein, "Learning Oracle PL/SQL", 2001)

"A callable set of execution instructions. Methods specify a contract; that is, they have a name, a number of parameters, and a return type. Clients that need to call a method must satisfy the contract when calling the method. Several kinds of methods are possible, such as instance and static." (Damien Watkins et al, "Programming in the .NET Environment", 2002)

"A procedure associated with a Java class or interface." (Peter Gulutzan & Trudy Pelzer, "SQL Performance Tuning", 2002)

"A procedure that belongs to a class and can be executed by sending a message to a class object or to instances from the class." (Stephen G Kochan, "Programming in Objective-C", 2003)

"Java code is organized into methods that are named and declared to have specific input parameters and return types. All methods are members of a class." (Marcus Green & Bill Brogden, "Java 2™ Programmer Exam Cram™ 2 (Exam CX-310-035)", 2003)

"In the UML, the specific implementation or algorithm of an operation for a class. Informally, the software procedure that can be executed in response to a message." (Craig Larman, "Applying UML and Patterns", 2004)

"Operations on an object that are exposed for use by other objects or applications." (Bob Bryla, "Oracle Database Foundations", 2004)

"A named collection of statements, with or without arguments, and a return value. A member of a class." (Michael Fitzgerald, "Learning Ruby", 2007)

"A function that is associated exclusively with an instance, either defined in a class, trait, or object definition. Methods can only be invoked using the object.method syntax." (Dean Wampler & Alex Payne, "Programming Scala", 2009)

"A program module that acts on objects created from a class in an object-oriented program." (Jan L Harrington, "SQL Clearly Explained" 3rd Ed., 2010)

"(1) A piece of code provided by an object, such as a control, that a program can call to make the object do something. (2) A routine (that may or may not return a value) provided by a class." (Rod Stephens, "Start Here! Fundamentals of Microsoft® .NET Programming", 2011)

"A function that is defined by a class and can only be invoked in the context of the class or one of its instances." (Dean Wampler, "Functional Programming for Java Developers", 2011)

"A procedure implemented by a class." (Rod Stephens, "Stephens' Visual Basic® Programming 24-Hour Trainer", 2011)

"A procedure that belongs to a class and can be executed by sending a message to a class object or to instances from the class." (Stephen G Kochan, "Programming in Objective-C, 4th Ed.", 2011)

"In the object-oriented data model, a named set of instructions to perform an action. Methods represent realworld actions. Methods are invoked through messages." (Carlos Coronel et al, "Database Systems: Design, Implementation, and Management" 9th Ed, 2011)

"In object-oriented design and programming, a function bound to a class as part of its overall behavior, executed in response to a message." (DAMA International, "The DAMA Dictionary of Data Management", 2011)

"A kind of action that an object can take if you tell it to." (Jon Orwant et al, "Programming Perl, 4th Ed.", 2012)

"In object-oriented programming, a named code block that performs a task when called." (SQL Server 2012 Glossary, "Microsoft", 2012)

"Defined and repetitive approach used to broach particular types of problems." (Gilbert Raymond & Philippe Desfray, "Modeling Enterprise Architecture with TOGAF", 2014)

"A named algorithm that defines one aspect of the behavior of a class" (Nell Dale & John Lewis, "Computer Science Illuminated, 6th Ed.", 2015)

"In object-oriented programming, a piece of code that makes an object do something." (Rod Stephens, "Beginning Software Engineering", 2015)

"The object-oriented programming term for a function or procedure." (Daniel Leuck et al, "Learning Java" 5th Ed., 2020)

OOP: Polymorphism (Definitions)

"Literally, from the Greek for many forms, and refers to the ability of different objects to respond differently to the same commands." (Greg Perry, "Sams Teach Yourself Beginning Programming in 24 Hours" 2nd Ed., 2001)

"The ability to treat many sub-types as if they were of the same base type." (Jesse Liberty, "Sams Teach Yourself C++ in 24 Hours" 3rd Ed., 2001)

"The capability of objects from different classes to accept the same message." (Stephen G Kochan, "Programming in Objective-C", 2003)

"The concept that two or more classes of objects can respond to the same message in different ways, using polymorphic operations. Also, the ability to define polymorphic operations." (Craig Larman, "Applying UML and Patterns", 2004)

"In object-oriented design, the principle that the same definition can be used with different types of data (specifically, different class implementations), resulting in more general and abstract implementations." (David C Hay, "Data Model Patterns: A Metadata Map", 2010)

"The redefinition of the body of a superclass method inherited by a subclass. The polymorphic method retains the same signature." (Jan L Harrington, "SQL Clearly Explained" 3rd Ed., 2010)

"The ability of a piece of code to work with more than one type." (Mark C Lewis, "Introduction to the Art of Programming Using Scala", 2012)

"The notion that you can tell an object to do something generic, and the object will interpret the command in different ways depending on its type." (Jon Orwant et al, "Programming Perl, 4th Ed.", 2012)

"The ability of a language to determine at runtime which of several possible methods will be executed for a given invocation" (Nell Dale & John Lewis, "Computer Science Illuminated" 6th Ed., 2015)

"The ability to treat a child object as if it were actually from a parent class. For example, it lets you treat a Student object as if it were a Person object because a Student is a type of Person." (Rod Stephens, "Beginning Software Engineering", 2015)

"Two objects can receive the same input and have different outputs." (Adam Gordon, "Official (ISC)2 Guide to the CISSP CBK" 4th Ed., 2015)

"The ability of an object variable to reference objects of different classes at different times during the execution of a program" (Nell Dale et al, "Object-Oriented Data Structures Using Java" 4th Ed., 2016)

"One of the fundamental principles of an object-oriented language. Polymorphism states that a type that extends another type is a “kind of” the parent type and can be used interchangeably with the original type by augmenting or refining its capabilities." (Daniel Leuck et al, "Learning Java" 5th Ed., 2020)

OOP: Visibility (Definitions)

[COM Visibility:] "Indicates whether a .NET type or member is accessible from COM. Anything public in .NET is visible to COM unless it’s marked with the ComVisibleAttribute custom attribute with its argument set to false, or its containing assembly is marked with the attribute with its argument set to false." (Adam Nathan, ".NET and COM: The Complete Interoperability Guide", 2002)

"The level of access granted to other classes or variables. Indicates whether something can be 'seen' from a location in a program." (Marcus Green & Bill Brogden, "Java 2™ Programmer Exam Cram™ 2 (Exam CX-310-035)", 2003)

"The ability to see or have reference to an object." (Craig Larman, "Applying UML and Patterns", 2004)

"Ability to enforce fine-grained access to and operations on data at the record, attribute, and attribute-value levels based on user entitlements and data usage and access policies." (Alex Berson & Lawrence Dubov, "Master Data Management and Data Governance", 2010)

"An attribute of operation in object-oriented design that tells whether the operation can be 'seen' by any program, or whether it is 'private' - only accessible within the model involved." (David C Hay, "Data Model Patterns: A Metadata Map", 2010)

"The scope in which a declared type or type member is visible to other types and members." (Dean Wampler, "Functional Programming for Java Developers", 2011)

OOP: Inheritance (Definitions)

"Creating a new type that can extend the characteristics of an existing type." (Jesse Liberty, "Sams Teach Yourself C++ in 24 Hours" 3rd Ed., 2001)

"The ability of one data object to gain characteristics from another object." (Greg Perry, "Sams Teach Yourself Beginning Programming in 24 Hours" 2nd Ed., 2001)

"The process of passing methods and instance variables from a class, starting with the root object down to subclasses." (Stephen G Kochan, "Programming in Objective-C", 2003)

"A feature of object-oriented programming languages by which classes may be specialized from more general superclasses. Attributes and method definitions from superclasses are automatically acquired by the subclass." (Craig Larman, "Applying UML and Patterns", 2004)

"Acquiring the properties of the parent, or base object, in a new object." (Bob Bryla, "Oracle Database Foundations", 2004)

"The ability of a class to inherit features from another class via the < operator. See multiple inheritance, single inheritance." (Michael Fitzgerald, "Learning Ruby", 2007)

"A strong relationship between one class or trait and another class or trait. The inheriting (derived) class or trait incorporates the members of the parent class or trait, as if they were defined within the derivative. The derivative may override inherited members (in most cases). Instances of a derivative are substitutable for instances of the parent." (Dean Wampler & Alex Payne, "Programming Scala", 2009)

"A general to specific relationship between classes in an object-oriented environment." (Jan L Harrington, "SQL Clearly Explained 3rd Ed. ", 2010)

"A strong coupling between one class or interface and another. The inheriting (derived) class or interface incorporates the members of the parent class or interface, as if they were defined within the derivative. Hence, inheritance is a form of reuse. The derivative may override inherited members (unless declared final). For a properly defined derived type, instances of it are substitutable for instances of the parent, satisfying the Liskov Substitution Principle." (Dean Wampler, "Functional Programming for Java Developers", 2011)

"The process of passing methods and instance variables from a class, starting with the root object, down to subclasses." (Stephen G Kochan, "Programming in Objective-C" 4th Ed., 2011)

"What you get from your ancestors, genetically or otherwise. If you happen to be a class, your ancestors are called base classes and your descendants are called derived classes. See single inheritance and multiple inheritance." (Jon Orwant et al, "Programming Perl" 4th Ed., 2012)

"Building a class from the basic functionality of an existing class and then adding new functions." (Matt Telles, "Beginning Programming", 2014)

"A mechanism by which one class acquires the properties - data fields and methods - of another class" (Nell Dale & John Lewis, "Computer Science Illuminated" 6th Ed., 2015)

"An important feature of object-oriented programming that involves defining a new object by changing or refining the behavior of an existing object. Through inheritance, an object implicitly contains all of the non-private variables and methods of its superclass. Java supports single inheritance of classes and multiple inheritance of interfaces." (Daniel Leuck et al, "Learning Java" 5th Ed., 2020)

OOP: Interface (Definitions)

"A contract that specifies the members a class or struct can implement to receive generic services for that type." (Jesse Liberty, "Programming C#" 2nd Ed., 2002)

"In Java, an interface is similar to a class definition, except that no detailed implementation of methods is provided. A class that implements an interface must provide the code to implement the methods. You can think of an interface as defining a contract between the calling method and the class that implements the interface." (Marcus Green & Bill Brogden, "Java 2™ Programmer Exam Cram™ 2 (Exam CX-310-035)", 2003)

"A set of signatures of public operations." (Craig Larman, "Applying UML and Patterns", 2004)

"A defined set of properties, methods, and collections that form a logical grouping of behaviors and data. Classes are defined by the interfaces that they implement. An interface can be implemented by many different classes." (Jim Joseph et al, "Microsoft SQL Server 2008 Reporting Services Unleashed", 2009)

"The specification of the means by which services can be invoked and data can be manipulated across an encapsulation boundary (e.g., class)." (Bruce P Douglass, "Real-Time Agility", 2009)

"The externally visible definition of the operations permitted on an application component." (David Lyle & John G Schmidt, "Lean Integration", 2010)

"Defines a set of members that a class can provide." (Rod Stephens, "Start Here! Fundamentals of Microsoft .NET Programming", 2011)

"Defines public properties, methods, and events that a class must provide to satisfy the interface." (Rod Stephens, "Stephens' Visual Basic Programming 24-Hour Trainer", 2011)

"A defined set of properties, methods, and collections that form a logical grouping of behaviors and data." (Microsoft, "SQL Server 2012 Glossary", 2012)

"The services a piece of code promises to provide forever, in contrast to its implementation, which it should feel free to change whenever it likes." (Jon Orwant et al, "Programming Perl" 4th Ed., 2012)

"A keyword used to declare an interface." (Daniel Leuck et al, "Learning Java" 5th Ed., 2020)

OOP: Class Diagram (Definitions)

"A Unified Modeling Language (UML) design artifact that shows the object classes and associations that exist between them. This is the rough UML equivalent of a data model." (Sharon Allen & Evan Terry, "Beginning Relational Data Modeling" 2nd Ed., 2005)

"A conceptual data model; a model of the static relationships between data elements of a system (similar to an ER diagram)." (Toby J Teorey, "Database Modeling and Design" 4th Ed., 2010)

"A type of diagram that shows a system's classes, contents, attributes, and relationships, including inheritance. UML is a common format for a class diagram." (DAMA International, "The DAMA Dictionary of Data Management", 2011)

"A type of static structure diagram that describes the structure of a system by showing the system's classes, their attributes, operations (or methods), and the relationships among the classes." (IQBBA, "Standard glossary of terms used in Software Engineering", 2011)

"Used to represent data and their relationships in UML object modeling system notation." (Carlos Coronel et al, "Database Systems: Design, Implementation, and Management" 9th Ed., 2011)

"In UML, a diagram that describes the classes that make up the system, their properties and methods, and their relationships." (Rod Stephens, "Beginning Software Engineering", 2015)

OOP: Instance (Definitions)

"A concrete representation of a class. Instances are objects that are typically created by sending an alloc or new message to a class object." (Stephen G Kochan, "Programming in Objective-C", 2003)

"An object of a particular class is called an instance of that class." (Marcus Green & Bill Brogden, "Java 2 Programmer Exam Cram 2 (Exam CX-310-035)", 2003)

"An individual member of a class. In the UML, called an object." (Craig Larman, "Applying UML and Patterns", 2004)

"A concrete representation of a class. Instances are objects that are typically created by sending an alloc or new message to a class object." (Stephen G Kochan, "Programming in Objective-C" 4th Ed., 2011)

"A specific object that is of a class type." (Rod Stephens, "Start Here! Fundamentals of Microsoft .NET Programming", 2011)

"An instance of a class is an object of the class's type. Different instances of the same class have the same properties, methods, and events but they may have different property values." (Rod Stephens, "Stephens' Visual Basic Programming 24-Hour Trainer", 2011)

"Another term for an object created by invoking a class constructor or a value of a primitive type." (Dean Wampler, "Functional Programming for Java Developers", 2011)

"(1) An occurrence of an entity. (2) The implementation of a database server (e.g., an Oracle instance)." (Craig S Mullins, "Database Administration: The Complete Guide to DBA Practices and Procedures 2nd Ed", 2012)

"In a map pattern one invocation of an elemental function on one element of the map." (Michael McCool et al, "Structured Parallel Programming", 2012)

"Short for 'an instance of a class', meaning an object of that class." (Jon Orwant et al, "Programming Perl" 4th Ed., 2012)

"One occurrence of something that has many occurrences, such as entities or objects." (James Robertson et al, "Complete Systems Analysis: The Workbook, the Textbook, the Answers", 2013)

"An entity to which a set of operations can be applied and that has a state that stores the effects of the operations." (Sybase, "Open Server Server-Library/C Reference Manual", 2019)

"An occurrence of something, usually an object. When a class is instantiated to produce an object, we say the object is an instance of the class." (Daniel Leuck et al, "Learning Java, 5th Ed.", 2020)

OOP: Class (Definitions)

"In object-oriented software design, a blueprint or set of specifications that defines the characteristics of an object and describes how the object should behave. In Object Role Modeling, an object role model can be used as the basis for an entity-relationship-attribute logical data model. The data can then be easily shared with other applications in the enterprise to form an enterprise logical model. In Microsoft Repository, an information model includes classes, relationships, and properties. This information model can be shared across the enterprise." (Microsoft Corporation, "Microsoft SQL Server 7.0 Data Warehouse Training Kit", 2000)

"A description of an object and its properties." (Greg Perry, "Sams Teach Yourself Beginning Programming in 24 Hours" 2nd Ed., 2001)

"The definition of a new type. A class is implemented as data and related functions." (Jesse Liberty, "Sams Teach Yourself C++ in 24 Hours" 3rd Ed., 2001)

"The specification of an object type in object-oriented programming (OOP), although not all OOP languages use this term." (Bill Pribyl & Steven Feuerstein, "Learning Oracle PL/SQL", 2001)

"An extendable reference type that combines data and functionality into one unit." (Jesse Liberty, "Programming C# "2nd Ed., 2002)

"A set of instance variables and methods that have access to those variables. After a class is defined, instances of the class (that is, objects) can be created." (Stephen G Kochan, "Programming in Objective-C", 2003)

"In the UML, “The descriptor of a set of objects that share the same attributes, operations, methods, relationships, and behavior” [RJB99]. May be used to represent software or conceptual elements." (Craig Larman, "Applying UML and Patterns", 2004)

"A collection of code, including methods and variables called members. The code in a class sets the rules for objects of the given class. See instance, module, object." (Michael Fitzgerald, "Learning Ruby", 2007)

"A template for instances that will have the same fields, representing state values, and the same methods. Scala classes support single inheritance and zero or more mixin traits. Contrast with type." (Dean Wampler & Alex Payne, "Programming Scala", 2009)

"The specification of an object instance; an encapsulation boundary including data (attributes) and behavior (operations that manipulate that data)." (Bruce P Douglass, "Real-Time Agility: The Harmony/ESW Method for Real-Time and Embedded Systems Development", 2009)

"A declaration of data and methods that describe a single entity and that will be used as a template to create objects." (Jan L Harrington, "SQL Clearly Explained" 3rd Ed., 2010)

"A set of instance variables and methods that have access to those variables. After a class is defined, instances of the class (that is, objects) can be created." (Stephen G Kochan, "Programming in Objective-C" 4th Ed., 2011)

"A template for creating instances. A class defines implementation of methods and fields. A class defines type." (Dean Wampler, "Functional Programming for Java Developers", 2011)

"Defines a data type with properties, methods, events, and other code encapsulated in a package. After you define a class, you can make as many instances of that class as you like. Very similar to a structure except classes are reference types, whereas structures are value types." (Rod Stephens, "Stephens' Visual Basic Programming 24-Hour Trainer", 2011)

"A construct that works as the blueprint for objects." (Mark C Lewis, "Introduction to the Art of Programming Using Scala", 2012)

"A user-defined type, implemented in Perl via a package that provides (either directly or by inheritance) methods (that is, subroutines) to handle instances of the class (its objects). See also inheritance." (Jon Orwant et al, "Programming Perl" 4th Ed., 2012)

"The encapsulation of a set of functions and data that model a real-world object. Creating a class is like creating a blueprint for a bunch of objects of a given type." (Matt Telles, "Beginning Programming", 2014)

"In object-oriented programming, a construct that defines a type (or class) of items. For example, if you define a Customer class, you can then create many Customer objects representing different real-world customers." (Rod Stephens, "Beginning Software Engineering", 2015)

"In C++, a user-defined data type. A class data type can contain both data representations (data members) and functions (member functions). A description of a set of objects that share the same attributes, operations, methods, relationships, and semantics. A class can use a set of interfaces to specify collections of operations that it provides to its environment." (Sybase, "Open Server Server-Library/C Reference Manual", 2019)

"Abstract entity that represents a kind of things in the world and may serve as semantic type of other entities." (Panos Alexopoulos, "Semantic Modeling for Data", 2020)

"The fundamental unit that defines an object in most object-oriented programming languages. A class is an encapsulated collection of variables and methods that may have privileged access to one another. Usually a class can be instantiated to produce an object that’s an instance of the class, with its own unique set of data." (Daniel Leuck et al, "Learning Java, 5th Ed.", 2020)