Challenge 1 — Solution

Task: Define a class Animal with a constructor taking name, and a
method speak() logging "{name} makes a sound." Create two Animal
instances with different names and call speak() on each.

class Animal {
    constructor(name) {
        this.name = name;
    }

    speak() {
        console.log(`${this.name} makes a sound.`);
    }
}

const cat = new Animal("Whiskers");
const cow = new Animal("Bessie");

cat.speak();
cow.speak();


Expected output:

Whiskers makes a sound.
Bessie makes a sound.


Notes:
- this.name inside speak() refers to whichever instance speak() was
  called on — cat.speak() uses cat's name, cow.speak() uses cow's,
  even though both instances share the exact same speak method
  definition.
- The constructor runs automatically the moment new Animal(...) is
  called, immediately setting this.name before anything else happens.
- Each instance is completely independent — changing cat.name later
  would have no effect on cow.name.