What is the difference between class,base class,sub class, super class in java?

A subclass inherits all of the public and protected members of its parent, no matter what package the subclass is in. If the subclass is in the same package as its parent, it also inherits the package-private members of the parent. You can use the inherited members as is, replace them, hide them, or supplement them with new members: In the Java language, classes can be derived from other classes, thereby inheriting fields and methods from those classes. Definitions: A class that is derived from another class is called a subclass (also a derived class, extended class, or child class). The class from which the subclass is derived is called a superclass (also a base class or a parent class). Excepting Object, which has no superclass, every class has one and only one direct superclass (single inheritance). In the absence of any other explicit superclass, every class is implicitly a subclass of Object. Classes can be derived from classes that are derived from classes that are derived from classes, and so on, and ultimately derived from the topmost class, Object. Such a class is said to be descended from all the classes in the inheritance chain stretching back to Object.

A class, as you should know, is a data structure with functions class MyClass { int myvar; public void myfunction() { } Classes have a thing called inheritance, meaning one class can be compatible with another class, even replacing it's functions with it's own. A base class is a class that a class inherits (so it can be compatible with it). A class which inherits a base class is called a sub class. A class inherits another class with the "extends" keyword. class MyBaseClass { virtual void MyFunc() { //Do nothing } } class MySubClass extends MyBaseClass { @Override void MyFunc() { //This func will be called instead of the one in MyBaseClass } } A class which inherits another class can be used instead of the base class. If you were able to subclass "int", you could use your subclass in place of int, possibly adding more functions as well.