Classes & Object-Oriented Programming
Build with object-oriented programming principles. Learn about classes, constructors, methods, inheritance, encapsulation, and polymorphism. Create reusable, maintainable code using OOP design patterns.
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What You'll Learn
Class declaration and instantiation
Constructors and initialization
Instance methods and properties
Inheritance and extends keyword
Encapsulation and access modifiers
Polymorphism and method overriding
Frequently Asked Questions
What is the difference between a class and an object?
A class is a blueprint or template that defines the structure and behavior of objects. An object is an instance of a class - a concrete realization with actual data. You can create many objects from one class.
What is inheritance and when should I use it?
Inheritance allows a class to inherit properties and methods from a parent class, promoting code reuse. Use it when you have an "is-a" relationship (e.g., Dog is-a Animal) and want to share common functionality.
What is encapsulation and why is it important?
Encapsulation is hiding internal implementation details and exposing only what's necessary through public methods. It improves maintainability, prevents unintended modifications, and makes code more modular.
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