What is object-oriented programming (OOP)?

OOP is a way to write code by creating objects that bundle data and actions together, like digital blueprints for reusable parts instead of one long list of instructions.

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What is object-oriented programming (OOP)?

Python gneurone encyclopedia
OOP is a way to write code by creating objects that bundle data and actions together, like digital blueprints for reusable parts instead of one long list of instructions.

definition

OOP stands for object-oriented programming, a style that organizes code around objects created from classes. Each class defines data (attributes) and behaviors (methods) that the objects will have.

Python supports OOP fully with features such as inheritance, encapsulation, and polymorphism, allowing developers to build modular programs that are easier to maintain and extend over time.

Think of a cookie cutter as a class and each baked cookie as an object: the cutter sets the shape and size once, then you can make many cookies that all follow the same rules but can have different decorations.

key takeaways

  • OOP groups related data and functions into single units called objects.
  • Inheritance lets new classes reuse code from existing ones without rewriting it.
  • Encapsulation hides internal details so other code cannot break them easily.
  • Polymorphism allows the same method name to work differently on different objects.
  • Python implements OOP with simple syntax using the class keyword and self parameter.

the 2026 job market

OOP skills stay required for most Python roles in 2026, especially backend web development, data pipelines, and automation scripting, as companies continue to favor maintainable codebases over procedural scripts.

Python Developer · US $95k-135k / Canada $85k-120k / UK £55k-80kSoftware Engineer (Python) · US $110k-160k / Canada $100k-140k / UK £65k-95k

frequently asked questions

What are the four main principles of OOP?

The four principles are encapsulation, inheritance, polymorphism, and abstraction. They help keep code organized, reusable, and protected from unintended changes.

How do you create a class in Python?

Use the class keyword followed by the name and a colon, then indent methods and attributes inside. The __init__ method sets up each new object.

Is OOP better than functional programming in Python?

Neither is universally better. OOP suits projects needing clear data models and reuse, while functional styles work well for data transformations. Many Python programs mix both approaches.

Can you use OOP for data science in Python?

Yes. Libraries like pandas and scikit-learn rely on OOP under the hood, and writing custom classes helps organize complex analysis pipelines and reusable models.

courses to go further

$ cat ./full-guide.mdPython Intermédiaire POO en pratique : le code et les commandes qui comptent vraimentread the guide →

related terms

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Auteur(s)

R

REHOUMA Haythem

Haythem Rehouma est un ingénieur et architecte IA et cloud, formateur et enseignant technique, avec un profil orienté IA médicale, AWS, MLOps, LLM/RAG et vision par ordinateur.