Anyone to explain this code for my better understanding?

Question

//here is the code
class Animal {
public void animalSound() {
System.out.println("The animal makes a sound");
}
}

class Pig extends Animal {
public void animalSound() {
System.out.println("The pig says: wee wee");
}
}

class Dog extends Animal {
public void animalSound() {
System.out.println("The dog says: bow wow");
}
}

class MyMainClass {
public static void main(String[] args) {
Animal myAnimal = new Animal();
Animal myPig = new Pig();
Animal myDog = new Dog();
//please explain the code three rows before this comment! Why the words in front of the object for them are all Animal? Thank you.
myAnimal.animalSound();
myPig.animalSound();
myDog.animalSound();
}
}

Answer 1

Animal myPig = new Pig
the word animal in front means that myPig inherits the animal class, then new Pig means that myPig also inherits the Pig class

Answer 2

Are you referring to why it says new pig and new dog?

Answer 3

That's the polymorphism in play. Since Pig and Dog extend Animal you can use the parent class (Animal as a type and then declare the object as its child)