First Move (11~18) - Code, Learn, Build
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First Move (11~18) - Code, Learn, Build

Structured, level-based technology learning paths from foundational exploration to industry mastery.

Learning Domains

  • Python Programming (Active)
  • Computer Science Core
  • Web Development
  • AI & Machine Learning

Platform Architecture

  • Level-Based Progression
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  • Modular Code Execution Engine
  • Curated Official Resources

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← Java Enterprise Development|Level 1: Java Syntax & Object-Oriented Principles

5. Inheritance, Abstract Classes, Interfaces & Polymorphism

Lesson 5 of 25
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Inheritance, Abstract Classes, Interfaces & Polymorphism

Master object inheritance (extends), abstract classes, interface contracts (implements), default methods, and dynamic polymorphism.

Interfaces vs Abstract Classes Matrix

### Interfaces vs Abstract Classes - **Interface**: Contract establishing WHAT methods a class must implement. Supports multiple interface inheritance. - **Abstract Class**: Partial base class containing shared field state and method implementations. Single inheritance only.
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