Object-Oriented Programming 


Object-Oriented Programming 

Object-Oriented Programming is used in almost every aspect of the programming world. Its techniques allow programmers to design efficient and innovative programs.

Object-Oriented Programming is one of the essential concepts to understand when entering the field of software development. This article looks at what Object-Oriented Programming is all about and why it’s so necessary for aspiring programmers to understand the principles.

What Is Object-Oriented Programming?

Object-Oriented Programming (OOP) is a programming concept in which a programmer uses classes and objects to implement real-world things in software development, such as inheritance, hiding, and polymorphism.

The fundamental purpose of OOP is to connect data and required functions so that no other section of the code may access them. It is a notion that encompasses a myriad of important concepts. Let’s have a look at a few of them now.

Structure of Object-Oriented Programming

The following are the components that comprise Object-Oriented Programming:


Classes are user-defined data types and serve as the template for individual objects, properties, and actions.


Objects are instances of a class that are formed with specific data. They are designed to represent real-world objects or abstract entities. When a class is first defined, the description is the sole object defined.


Methods are functions specified within a class that describe an object’s characteristics. A reference to an instance object is the first step in defining a method in a class declaration.

Throughout the program, methods can be used. Methods are used by programmers to ensure reusability or to keep functionality confined within a single object at a time.


Attributes are defined in the class template and represent an object’s condition. Data is saved in the object’s attributes field. Class characteristics are the property of the class itself.

Principles of Object-Oriented Programming

There are several key principles to understand in Object-Oriented Programming because they constitute the foundation of the OOP paradigm. 

The following are the four fundamental concepts of Object-Oriented Programming.


The process of encapsulating data into a single unit is known as encapsulation. It’s a powerful method for connecting a code to the data it manipulates.

The encapsulation functions similarly to a shield. It prohibits other portions of the code from accessing the data.

Technically, under encapsulation, a class’s variables or data are concealed from other classes and can only be accessible by any class member function in which they are specified. This concept is referred to as data hiding.

Encapsulation is implemented by declaring all variables in the class to be private. In the class, public methods are defined to set and retrieve variable values.

The following are some of the pros of encapsulation:

  • Other sections of the code cannot access private methods; only public methods and attributes are accessible from the outside.
  • Only public fields and methods are exposed, allowing developers to write code without fear of meddling from the outside world.
  • Outside developers can only access public methods since code is hidden in a class.
  • The majority of the code is updated and improved.
  • No one can see what’s hidden behind the thing.


Data abstraction is a valuable principle that only shows the user the important details. The trivial and non-essential information is not displayed to the user. 

An automobile, for example, is referred to simply as a car without reference to its internal components such as the engine, wheels, and so on.

Identifying only the required attributes of an object while omitting irrelevant information is known as data abstraction. 

For example, Interfaces and abstract classes are used to achieve abstraction in Java.

The following are some of the advantages of abstraction:

  • Simple, high-level user interfaces
  • It reduces the complexity of viewing things.
  • Only necessary aspects are shown to the user, which helps increase the security of an application or software.
  • Software maintenance is easier.
  • Code updates rarely change the abstraction.


Inheritance is one of the most significant and often used principles in Object-Oriented Programming.

Object-Oriented Programming relies heavily on inheritance. In Java, it is the technique that allows one class to inherit the features, properties, and methods of another.

Let’s go over some of the most commonly used key terminologies:

  • Super Class: A superclass is a class whose characteristics are inherited (or a base class or a parent class).
  • Sub Class: A subclass is a class that inherits from another class (or a derived class, extended class, or child class). The subclass can add its own fields and methods to the superclass’s fields and methods.

Inheritance encourages “reusability,” which indicates that if we want to create a new class but there is already one with some of the code we need, we can derive our new class from the existing similar block of code. The existing fields and functions are used in this way.

A few advantages of inheritance are enumerated below:

  • Code reusability refers to the ability to reuse code that has been written only once.
  • A single superclass can represent the number of subclasses in a hierarchy.
  • No changes to all base classes are required; just changes to the parent class are needed.
  • To develop more dominant objects, inheritance is used.
  • Inheritance prevents data duplication and redundancy.
  • To avoid both space and time complexity, inheritance is used.


Polymorphism is a core notion in Object-Oriented Programming (OOP) that describes instances when something appears in several forms. It is a programming notion that refers to the ability to access objects of diverse types using the same interface. 

Polymorphism has the following advantages:

  • Method Overriding

Overriding is a feature that allows a subclass or child class to implement a method that is already offered by one of its superclasses or parent classes. When a subclass’s method has the same name, parameters or signature and return type(or sub-type) as a method in its superclass, the subclass’s method is said to override the super-method. class’s

  • Method Overloading

When there are numerous functions with the same name but different parameters, it is referred to as overloading. Changes in the number of arguments or the kind of arguments can cause functions to become overloaded.

What is an Object in Programming? 

An instance of a class is referred to as an object or an entity. In OOPS, an object is a self-contained component with methods and attributes that make a specific sort of data accessible.  

For example, if the class is Car, the objects are the car’s engine, wheel, and colour, among others. 

When a message is sent to an object, you are requesting a call to execute one of the object’s methods defined in the class.

Properties of objects:  

  • State: The state of an item is represented by its characteristics. It also reflects an object’s attributes.
  • Behaviour: An object’s behaviour is represented by its methods and how it interacts with other objects. 
  • Identity: The object’s identity refers to its unique identifier and property, which allows it to communicate with other entities.
  • Method: A method is a collection of statements that do a single operation and return the outcome to the caller. Without returning anything, a method can perform a certain purpose. Methods allow us to reuse code without having to re-write it. 

Object-Oriented Programming Languages

Popular Object-Oriented Programming languages include Java, Python, C++, Lisp, and Perl. They support the concept of classes and objects in programming.

The following are five of the most widely used object-oriented languages:

  • Java: Java was created to be platform-agnostic and simple to learn, and it has since become the most popular language for Android app development. Without a shred of doubt, Java is one of the best and most widely used OOP languages today.
  • Python: Python is a general-purpose programming language that is popularly used in many tech fields. It also employs OOP ideas in the development of constructive and successful code. Python also has a large presence in machine learning and data science. It’s one of the most popular languages in that new and rapidly expanding field.
  • C++: C++ is another programming language used to create interpreters and compilers that aid in interpreting other programming languages. C++ essentially incorporates all of the concepts of C while refining them to make them faster and more adaptable for OOP use.
  • Ruby: Ruby is a programming language that is extremely similar to Python in terms of implementation and general use. Ruby is an Object-Oriented language with some functional features. Ruby’s syntax is fairly basic, and anyone who has worked with a modern programming language can understand and use it.
  • C#: C# is a Microsoft multi-paradigm programming language. C# is another widely used language for general-purpose programming and to meet OOP criteria. Because of its interoperability with the .NET Framework, C# is gaining popularity in the OOP community. It may also be used to create Windows desktop applications and Android mobile applications. 

There are a variety of other object-oriented languages. Perl, Objective-C, Dart, Lisp, JavaScript, and PHP are other object-oriented languages.

Key Benefits of Object-Oriented Programming 

Below are a few of the benefits of object oriented programming. 


Encapsulation allows products to be self-contained, making troubleshooting and collaborative development easier.


Because inheritance allows code to be reused, a developer does not have to write the same code several times.


OOP enhances productivity by allowing developers to combine existing libraries, and reusing code allows programmers to create new apps more quickly.

Easily Upgradable and Scalable 

Programmers can implement system features on their own.

Interface Descriptions 

External system descriptions are simple because message passing techniques are used for object communication.


With the help of encapsulation and abstraction, complex code is concealed, software maintenance is simplified, and internet protocols are protected.


A single function can adapt to the class to which it is allocated, and objects of various types can traverse via the same interface thanks to polymorphism.


Object-Oriented Programming is one of the fundamental variety of programming concepts. OOP contains a variety of useful features which help in making a more effective and compact code. We hope this article helped clear any doubts regarding OOP.

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