Before discussing the difference between OOP and POP, let us first look at some basic concepts of the programming process. There are many different approaches to a programming process when building solutions for various types of problems using programming. These approaches are known as programming paradigms. Most programming languages fall under one paradigm, but there could be languages that have elements of multiple paradigms. Object Oriented Programming (OOP) and Procedure Oriented Programming (POP) are two such programming paradigms. These two paradigms mainly differ due to the abstractions they create when designing a solution. An abstraction in a programming approach separates the relevance of information from the user’s perspective.The key difference between POP and OPP is that POP creates and uses procedural abstractions while OOP focuses on data abstractions.
What is OOP?
Object Oriented Programming (OOP) is based on two main concepts; objects and classes. Objects are the structures that contain both data and procedures for operating on that data. These objects can be used to model real world entities. Objects have two characteristics; state and behavior. Classes define the data formats and procedures for a given type or a class of objects. In other words, a class is a blueprint of an object.
OOP approach focuses mainly on data rather than on the algorithm for handling data. Since both data and functions that handle that data are bundled within objects, no modifications can be done on the data by external functions. That is, the data of an object cannot be accessed by functions of any other object. This ensures the security of the data of a program. But, functions of an object may access functions of another object allowing the objects to communicate with one another. This invoking of methods of one object by methods of another object is known as message passing.
OOP programming has four main features; abstraction, encapsulation, polymorphism, and inheritance. The purpose of abstraction is to show only relevant information to a user so that the complexity of a problem is reduced. Encapsulation is the localization of information within an object. The process of where one class acquires the properties and functionalities of another class is known as inheritance. Polymorphism is the feature of a function having many signatures or an object behaving in many different ways.
OOP also supports high modularity. Adding new functions or data does not require altering the complete program. It can simply be done by creating a new object since objects are independent to declare and define. Thus, OOP can be efficient and high in productivity.
Considering the programming design, OOP follows a bottom-up approach. Some popular OOP languages are Java, Python, Perl, VB.NET, and C++.
Python is a popular OOP language.
What is POP?
Procedure Oriented Programming (POP) views the problem as a sequence of things to be done and is based on the concept of procedure calls. Programs are divided into smaller sections called procedures – also known as routines, subroutines, methods or functions. Procedures emphasize on the algorithm of what needs to be done in a program. That is, a procedure contains a series of computational steps to be carried out. Because these functions are action-oriented, using POP languages might sometimes prove to be difficult when modeling real world problems.
POP focuses more on writing a list of instructions to inform the computer what to do step-by-step. Less attention is given to the data associated with the program. Data can be passed between the procedures and each procedure transforms the data from one form to another. Most of the data are global and can be accessed freely from any function in the system. And since POP does not support effective techniques for hiding the data, the program might be insecure. Some functions may have their own local data.
In POP, it might be difficult to identify what data is used by which functions at times since global data is largely shared between functions. In case, the existing data need to be changed, all the functions that have been accessing that data have to be revised as well.This might affect the whole program, and bugs and errors could surface.
Considering the programming design, POP languages employ a top-down approach. Because POP languages make explicit references to the state of the execution environment, they are also called imperative languages. Examples for such POP languages are COBOL, Pascal, FORTRAN, and C Language.
C is a popular POP language.
What is the difference between OOP and POP?
Definition of OOP and POP
OOP: Object Oriented Programming is a programming paradigm that focuses on data abstractions.
POP: Procedure Oriented Programming is a programming paradigm that focuses on procedural abstractions.
Features of OOP and POP
Problem Decomposition
OOP: In OOP approach, programs are divided into parts known as objects.
POP: in POP approach, programs are divided into functions.
Focus
OOP: The main focus of OOP is on the data associated with the program.
POP: The main focus of POP is on the procedures and algorithms that manipulate the data.
Designing Approach
OOP: OOP Follows a bottom-up approach.
POP: POP Follows a top-down approach.
Use of data
OOP: In OOP, each object controls data within it.
POP: In POP, most functions use global data.
Access to Data
OOP: In OOP, data of an object can only be accessed by the functions of that particular object.
POP: In POP, data can move freely from function to function.
Access Specifiers
OOP: OOP has access specifiers such as Public, Private, etc.
POP: POP does not have any access specifiers.
Security of Data
OOP: Since OOP provides data hiding, data associated with the program is secure.
POP: POP does not provide any data hiding methods. Therefore, the data is less secure.
Ease of Modification
OOP: OOP provides easy and efficient ways of adding new data and functions without revising existing program.
POP: In POP, if new data or functions need to be added, existing program has to be revised.
Used Languages
OOP: C++, Java, VB.NET, C#.NET, etc. are used by OOP.
POP: FORTRAN, Pascal, C, VB, COBOL, etc. are used by POP.
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