״יש-לו״ לעומת ״הוא-״

class Animal {
  constructor(name) {
    this.name = name;
  }
  
  eat() {
    console.log(`${this.name} is eating.`);
  }
}

// Dog "is-a" Animal - קשר ירושה
class Dog extends Animal {
  bark() {
    console.log(`${this.name} says woof!`);
  }
}

class Engine {
  start() {
    console.log("Engine started");
  }
}

// ל-Car "has-a" Engine - קשר של קומפוזיציה
class Car {
  constructor() {
    this.engine = new Engine(); // קומפוזיציה
  }
  
  startCar() {
    this.engine.start();
    console.log("Car is running");
  }
}