Difference Between OOP and POP

The main difference between OOP and POP is that the OOP divides the program into multiple objects to solve the problem while the POP divides the program into multiple procedures or functions to solve the problem.

A programming paradigm is a fundamental style of arranging the structure and the elements of a computer program. It defines the style and capabilities of a programming language. A programming language can be classified into one paradigm or more paradigms. OOP and POP are two common paradigms. OOP divides the program into objects. POP divides the program into functions. It is difficult to do modifications to the code and to model real-world scenarios using POP. OOP was introduced to overcome the limitations of POP.

Key Areas Covered

1. What is OOP
     – Definition, Features
2. What is POP
     – Definition, Features
3. Difference Between OOP and POP
     – Comparison of Key Differences

Key Terms

Abstraction, Encapsulation, Inheritance, OOP, POP, Polymorphism, Programming Paradigm

What is OOP

OOP (Object Oriented Programming) allows programmers to model real-world scenarios using objects.  An object is any entity that has a state and behavior. It is an instance of a class. A state is called the properties, attributes or data. Behavior is called a method. Student, Lecturer, Person, Course, Book, etc. are some examples of objects. These objects communicate with other objects by passing messages.

Figure 1: OOP

A class is a blueprint to create an object. Therefore, it is not possible to create objects without a class. For example, the object called Ann is created using the class Student. This object has states such as name, age, id, city, grade, and behaviors such as reading, walking, studying, eating, etc. The object and class are two fundamental concepts in OOP.

Furthermore, there are four major pillars in OOP. They are the inheritance, polymorphism, abstraction, and encapsulation. They are as follows.

Inheritance – When an object uses the properties and methods of an already existing object, it is called inheritance. It improves code reusability and maintainability.

Polymorphism – Allows an object to perform in multiple ways. Method overloading and method overriding are used to achieve polymorphism.

Abstraction – Hides the internal details and shows only the functionality. Abstract classes and interfaces are used to achieve abstraction.

Encapsulation – Binds the attributes and methods into a single unit.

Overall, OOP makes the development and maintenance easier. It secures the data and provides the ability to simulate real-world problems much more effectively.

What is POP

POP stands for Procedural Oriented Programming. This paradigm focuses on procedures or functions that are required to perform the computation. It focuses on the process, rather than on data.

In POP, the program is divided into multiple functions. Each function has a clearly defined purpose. A function is a set of instructions to perform a certain task. These functions share global variables. Data is exchanged among functions.

On the other hand, there are a few drawbacks to POP. Since all functions share the same global variables, data is not very secure. If new data is added, all the functions have to be modified to access the data. Furthermore, it is also difficult to model real-world scenarios in POP.

Difference Between OOP and POP

Definition

OOP is a programming paradigm based on the concept of objects, which contains data in the form of fields known as attributes, and code in the form of procedures known as methods. POP is a programming paradigm that is based upon the concept of the procedure calls. This is  the basic difference between OOP and POP.

Long Form

OOP stands for Object Oriented Programming. POP stands for Procedural Oriented Programming.

Main Emphasis

While OOP emphasis on objects, POP emphasizes on functions. This is one main difference between OOP and POP.

Program Decomposition

OOP divides the program into multiple objects. POP divides the program into multiple functions.

Modification

Modification is easier in OOP as the objects are independent. Modifications in POP can affect the entire program. Therefore, modifications are difficult in POP.

Communication

In OOP, the objects communicate with each other by passing messages. In POP, the functions communicate with each other by passing parameters.

Data Control

In OOP, each object controls its own data. In POP, the functions share global variables.

Data Hiding

It is possible to hide data in OOP. It avoids illegal access to the data or the attributes. Therefore, OOP makes data more secure. On the other hand, there is no data hiding mechanism in POP. This is another important difference between OOP and POP.

Assess Specifiers

OOP has access specifiers such as private, protected, and public to change the visibility of attributes and methods. There are no access specifiers in POP. This is also an important difference between OOP and POP.

Code Reusability

Although OOP has inheritance to reuse the already existing code, there is no inheritance in POP.

Programming Languages

C++, Java, and Python are a few languages that support OOP. C, Pascal, FORTRAN, and COBAL are few languages that support POP.

Conclusion

OOP and POP are two programming paradigms. The main difference between OOP and POP is that OOP divides the program into multiple objects to solve the problem while POP divides the program into multiple procedures or functions to solve the problem.

Image Courtesy:

1. “CPT-OOP-objects and classes” By Pluke – Own work (CC0) via Commons Wikimedia

Reference:

1. “Java OOPs Concepts – Javatpoint.” Www.javatpoint.com, Available here.
2. “Procedural Oriented Programming.” Bragg’s Equation, Available here.