Inheritance and Polymorphism
Of OOP's three defining traits, encapsulation, inheritance and
polymorphism, we have so far concentrated on encapsulation. In this
module we will turn our attention to inheritance and polymorphism.
Recall that inheritance enables one class to inherit the characteristics
of another one (where by characteristics we mean attributes and
methods). Polymorphism refers to the ability of the same operation to
trigger different behaviours in different contexts, or in syntactic
terms for the same operator, e.g. +
, to do different things to different
object types.