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What is Object-Oriented Programming?

Updated May 6, 2026

Short answer

OOP is a programming paradigm based on objects containing data and behavior.

Deep explanation

It includes four pillars: encapsulation, inheritance, polymorphism, and abstraction. It helps in modular, reusable, and maintainable code design.

Real-world example

Modeling real-world systems like a car rental system or banking system.

Common mistakes

  • Using OOP only as class creation without proper design principles.

Follow-up questions

  • What are OOP pillars?
  • Why is OOP important?

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