Teacher introduces the class hierarchy in the context of inheritance concept. Teacher introduces ancestor class (also known as: super class, parent class) and descendant classes (also known as: subclasses, child classes):

o   Previously examined real-life classes can be discussed in this context,

o   In this context, it should be discussed that subclasses can inherit properties (i.e., attributes and methods) from theparent class,

o   However, it should be discussed that subclasses can incorporate additional properties not available in the parent class,

Benefits of the class hierarchy in the context of inheritance conceptshould be discussed. It should be explained that in Java programing language each class can have multiple subclasses, but only one parent class. The role of the Object class in the context of class hierarchy and inheritance can be discussed.