One of the key features of object-oriented programming is that you can extend your classes. You extend a class to create another class, and the extended class is known as a subclass . The subclass inherits reference variables and class methods from the parent class, which is known as a superclass .
The properties of the parent class are inherited by the child class; because the properties from the parent class are extended to the child class, the parent class is also called the base class. For the same reason, the child class is known as the derived class, since ...
