Objective-C is the underlying programming language for iPhone application
development. It follows object-oriented programming (OOP) paradigm. Students who
take the iPhone course must have some background in OOP, usually either C++ or Java.
This way, course content on the language itself focuses only on the new features in
Objective-C that are essential to OOP, such as how to define a class, instantiate an object,
access the data fields of an object, define and invoke an action, represent the relations
between classes and objects through inheritance and polymorphism, and how to restrict
the behaviors of classes using protocols.