Object-oriented programming — Glossary

Object-oriented programming

(also OOP)

Object-oriented programming definition

Object-oriented programming is a programming paradigm that prioritizes objects over functions and logic.

See also: subtyping, ActiveX

Objects. Objects are instances of classes that contain data in the form of fields (attributes or properties) and code in the form of procedures (methods).
Classes. A blueprint for creating objects.
Inheritance. A mechanism where a new class can inherit properties and behaviors (methods) from an existing class.
Polymorphism. The ability of different objects to be treated as instances of the same class through inheritance.
Encapsulation. The bundling of data (attributes) and methods that operate on the data into a single unit or class.
Abstraction. It hides complex implementation details and shows only the essential features of an object.
Message passing. Objects communicate with one another through methods (functions bound to the objects) by passing messages.

Java. Developed by Sun Microsystems, it is one of the most widely used object-oriented languages. Its “write once, run anywhere” approach has made it popular for various application domains, including web, mobile, and enterprise applications.
C++. An extension of the C programming language, C++ was developed by Bjarne Stroustrup. It incorporates object-oriented features while retaining the power and flexibility of C.
Python. A versatile, high-level language that supports multiple programming paradigms, including OOP. Its simplicity and readability have made it popular for web development, data science, and artificial intelligence.
C# (C Sharp). Developed by Microsoft for its .NET framework, C# is a modern, object-oriented language used for developing Windows applications, web services, and games (especially with the Unity game engine).
Ruby. Known for its elegant and expressive syntax, Ruby is a pure object-oriented language. It gained immense popularity with the Ruby on Rails web development framework.
Objective-C. This language combines C with object-oriented capabilities inspired by Smalltalk.
Swift. Introduced by Apple to replace Objective-C for iOS, macOS, watchOS, and tvOS development.