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Class

PropertyValue
descriptionBlueprint to create objects.
tagsref

A class is a programming construct used as a blueprint or template for creating object instances.

Classes are central to object-oriented programming, where they group related data and behavior into one structured type.

What it does​

A class defines the structure and behavior that objects created from it will have.

It is commonly used to:

  • Define object properties and state
  • Group related methods and logic
  • Create reusable application types
  • Model domain concepts in code
  • Support abstraction and encapsulation

Core concepts​

Blueprint for objects​

A class describes what an object can contain and what it can do.

Objects are the actual instances created from that definition.

Data and behavior together​

Classes usually bundle fields or properties with methods.

That is a core idea in object-oriented design.

Language-specific feature set​

The exact meaning of class depends on the language.

Some languages make classes central, while others support different object models or multiple paradigms.

Common use cases​

  • Modeling business entities
  • Structuring application code
  • Building reusable components and services
  • Encapsulating logic and state
  • Organizing larger codebases

Practical notes​

  • A class is not the same as an object; it is the definition used to create objects.
  • Classes are common, but not every language or codebase relies on class-heavy design.
  • Good class design usually aims for clarity, cohesion, and clear responsibilities.
  • Classes often appear alongside methods, functions, and variables in language fundamentals.

Sources Used​

Frequently Asked Questions​

Is a class the same as an object?​

No. A class is the definition. An object is an instance created from that definition.

Do all languages use classes?​

No. Some languages do, while others use prototypes, structs, functions, or other models instead.

Is a class required for object-oriented programming?​

Not always. Some object-oriented languages support other ways of organizing objects and behavior.