OOP foundations

Abstract class vs Interface

An abstract class is a half-built base you EXTEND (one parent, shared code + state); an interface is a pure contract you IMPLEMENT (many of them, no state). Knowing which to reach for is a classic interview question. An animated lesson where the diagram draws itself as the design grows.

  • Lesson 8 of 8
  • Animated diagrams
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OOP foundations

  1. 1Objects & Classes
  2. 2Encapsulation
  3. 3Abstraction
  4. 4Inheritance
  5. 5Polymorphism
  6. 6Composition over Inheritance
  7. 7UML Relationships
  8. 8Abstract class vs Interface
8 lessons, each with diagrams that draw themselves.

What you will learn

  • Two ways to share a shape
  • Abstract class, a half-built base
  • Interface, a pure contract
  • The rule that decides it
  • Comparison

More low-level design

Watch Abstract class vs Interface take shape

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Sign in to open itSee plans

DSA comes with the all labs plan and every ChaiCode batch.