Complete Guide For Python Programming (2015)


Python is an object-oriented language and because of this creating and using classes and objects are quite easy.

Overview of OOP Terminology

Class: A user-defined prototype for an object that defines a set of attributes that characterize any object of the class. The attributes are data members and methods, accessed via dot notation.

Class variable: A variable that is shared by all instances of a class. Class variables are defined within a class but outside any of the class's methods. Class variables aren't used as frequently as instance variables are.

Data member: A class variable or instance variable that holds data associated with a class and its objects.

Function overloading: The assignment of more than one behavior to a particular function. The operation performed varies by the types of objects involved.

Instance variable: A variable that is defined inside a method and belongs only to the current instance of a class.

Inheritance: The transfer of the characteristics of a class to other classes that are derived from it.

Instance: An individual object of a certain class. An object ‘obj’ that belongs to a class Circle, for example, is an instance of the class Circle.

Instantiation: The creation of an instance of a class.

Method: A special kind of function that is defined in a class definition.

Object: A unique instance of a data structure that's defined by its class. An object comprises both data members and methods.

Operator overloading: The assignment of more than one function to a particular operator.