eg: Inheritance in Java

Inheritance.java

class Teacher {
    String designation = "Teacher";
    String collegeName = "CMU";

    void does() {
        System.out.println("teaching");
    }
}

public class MathsTeacher extends Teacher {
    String mainSubject = "Maths";

    public static void main(String[] arg) {
        MathsTeacher mt = new MathsTeacher();
        System.out.println(mt.collegeName);
        System.out.println(mt.designation);
        System.out.println(mt.mainSubject);
        mt.does();
    }
}
/**
 * OUTPUT:
 * CMU
 * Teacher
 * Maths
 * teaching
 * <p>
 * Based on the example, the MathsTeacher class is a child class of Teacher.
 * The child class MathsTeacher forms a IS-A relationship with the parent class Teacher.
 */