Objects First: OOP Fundamentals

Object-oriented programming from why it exists through SOLID, composition vs. inheritance, anti-patterns, and applied design exercises. TypeScript and Python.

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01Chapter 1: Why Object Orientation Exists 02Chapter 2: Classes, Objects, and Instances, Precisely Defined 03Chapter 3: The Four Pillars I: Encapsulation 04Chapter 4: The Four Pillars II: Abstraction 05Chapter 5: The Four Pillars III: Inheritance 06Chapter 6: The Four Pillars IV: Polymorphism 07Chapter 7: Composition vs. Inheritance 08Chapter 8: Interfaces and Abstract Classes: When to Use Which 09Chapter 9: SOLID, Part 1: Single Responsibility & Open/Closed 10Chapter 10: SOLID, Part 2: Liskov Substitution, Interface Segregation, Dependency Inversion 11Chapter 11: Basic UML for Communicating Design 12Chapter 12: Anti-Patterns: God Objects, Tight Coupling, Deep Hierarchies, the Fragile Base Class, Anemic Domain Models 13Chapter 13: OOP Idioms Across TypeScript and Python — and Where OOP Is the Wrong Tool 14Chapter 14: When OOP Breaks Down: Real-World Failure Modes 15Chapter 15: Design Exercise: Parking Lot System 16Chapter 16: Design Exercise: Library Management System 17Chapter 17: Design Exercise: Elevator Controller 18Chapter 18: OOP in Interviews: What a Strong Answer Looks Like

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Python DSA — Course Python DSA — Interview Prep Python DSA — Beginner Python Syntax & DSA Reference Git Mastery Cognitive Skills & Mental Tools Code Optimization Rules Patterns of Good Design Under the Hood: Operating Systems How the Bytes Travel: Networking Data at Rest, Data in Motion: Databases Sharing Time: Concurrency & Multithreading Clean by Default: Coding Standards The Review: Code Review From Idea to Production: the SDLC Designing at Scale: System Design Whiteboard to Blueprint: HLD & LLD Built to Last: Reliability & Scaling Tell Me About a Time: Behavioral Interviews