What is the role and purpose of the 'super' keyword in Java?

The keyword super in Java is used to refer to members (methods or fields) of the superclass from a subclass. It allows:

• Calling the superclass constructor from the subclass constructor (super()), which is mandatory if the superclass does not have a no-argument constructor.
• Accessing superclass methods if they are overridden in the subclass, for example, super.methodName().
• Accessing superclass fields if they are hidden by fields with the same name in the subclass.

Example:

class Animal {
    void sound() {
        System.out.println("Animal sound");
    }
}

class Dog extends Animal {
    void sound() {
        super.sound(); // call to superclass method
        System.out.println("Bark");
    }
}

public class Main {
    public static void main(String[] args) {
        Dog dog = new Dog();
        dog.sound();
    }
}

Output:

Animal sound
Bark