Object-Oriented Programming

Overview of the five principles for maintainable, scalable object-oriented design

Hide complexity and expose only essential interfaces to simplify how we interact with objects

A class should have one, and only one, reason to change

Protect internal state and enforce access through controlled interfaces

Software entities should be open for extension but closed for modification

Create new classes based on existing ones to promote code reuse and establish hierarchies

Objects of a superclass should be replaceable with objects of its subclasses without affecting program correctness

Clients should not be forced to depend on interfaces they do not use

Allow objects to take multiple forms, enabling flexible and extensible code

High-level modules should not depend on low-level modules; both should depend on abstractions

Understanding when to use interfaces versus abstract classes in your design