•Inheritance is the way to model
this “subset” relationship.
•A class, called a subclass or derived class inherits from
a class (a superclass, parent, or base class), if its objects form a subset of the base
class objects
•The objects in the
subclass must support all operations that are supported by the
superclass, but they may carry out these operations in a special way.
•They may also support additional
operations
•Think about bank
accounts – do checking and savings accounts differ in any way? Are they
separate classes or instances of the same class? Is there anything common between them?