Top 25 Object Oriented Programming Interview Questions and Answers in 2024

Editorial Team

Object Oriented Programming Interview Questions and Answers

If you’re looking to land a position in object-oriented programming (OOP) role, then you’ll need to be up to speed on the basics of this popular programming language. This comprehensive guide will teach you all about the most common OOP interview questions and answers so that you’ll be well-prepared for any potential interviews.

1. OOP – What Is It?

Object-Oriented Programming is a programming paradigm that emphasizes the use of objects, which are reusable entities with properties and methods. An object’s properties can be accessed and changed by invoking its methods. The process of creating and using objects is called object orientation.

2. What Does The Term OOP Mean?

Object-Oriented Programming is a computer programming paradigm that encourages the reuse of object structures and methods across multiple applications. In an OOP program, individual objects are treated as autonomous entities with their own properties and methods.

I first learned about OOP while working on my undergraduate degree in computer science. I found that I could more easily code problems in a modular fashion by breaking them down into smaller, more manageable tasks. This made it easier to track down and fix errors. Furthermore, using objects allowed me to communicate my intentions more clearly to other developers. Thus, I can say that I am intimately familiar with the benefits of using OOP in software development.

3. Describe Basic OOP Concepts?

Object-Oriented Programming (OOP) is a way of writing code that makes it easier to understand and manage. It allows you to create programs that are structured in a way that is similar to the way objects work in the real world. This makes it easier to understand and manage your programs. OOP also allows you to use functions to create reusable code.

4. OOP: What Are Its Roles?

Object-Oriented Programming is a programming paradigm that emphasizes the use of objects to model data. In an object-oriented program, each object represents a unique entity and is able to interact with other objects to perform tasks. This interaction occurs through the use of methods, which are routines that operate on the data related to the object.

The roles of OOP in an interview vary depending on the position being filled. Regardless of the role you are interviewing for, it is important to be familiar with OOP concepts so that you can demonstrate your understanding during the interview. If you are not familiar with OOP concepts, consider reviewing some introductory tutorials before your interview.

5. OOP: What Are The Benefits?

There are many benefits to using Object Oriented Programming (OOP) when programming. OOP can help reduce code duplication, make code more readable and maintainable, and improve overall development efficiency. Additionally, OOP can help you design more effective algorithms and architectures.

When I first started learning about OOP, I found that it made a lot of sense. I found that I could easily see how my code was organized and how it worked together. This made it much easier for me to debug and troubleshoot problems.

Additionally, I found that I could easily create reusable components and classes. This made my code more robust and easier to maintain. Overall, I believe that using OOPs has been a huge benefit for me in my programming career. I strongly recommend anyone looking to improve their skills in this area consider adopting OOPs into their development process.

6. How Do You Deal With OOP Programming?

I usually wake up early and work on my projects for a few hours before breakfast. I like to have a consistent routine so that I can stay focused and avoid any distractions. After breakfast, I typically take a break for lunch and then continue working on my projects until dinner. I try to make time for fun too, but I always come back to my work later in the evening.

7. When Does OOP Differ From SOP?

When I was preparing for my OOP interview, I read a lot about the difference between OOP and SOP. I was initially confused by the terminology because they both sound like they are related to the same thing. However, OOP is a different way of thinking about programming that focuses on objects and their dependencies. SOP is a specific way of implementing OOP in a company or organization.

I think the main difference between OOP and SOP is that OOP emphasizes object-oriented design, while SOP deals with the practical aspects of implementing it in an organization. For example, SOP might focus on how to structure code so that it is easy to maintain and understand.

8. Why Does OOP Have Such A High Level Of Flexibility?

Object-Oriented Programming is a programming paradigm that emphasizes the use of objects to model real-world objects and their relationships. OOP provides a way to modularize code, create reusable components, and encapsulate complex logic. OOP is often used in software development because it makes code more readable and maintainable.

Before my interview for an Object-Oriented Programming position, I read up on the concept. I knew that OOP was a popular programming paradigm, but I wasn’t really sure what it entailed. Once I understood what the basics were, I started to appreciate its benefits. One of the main advantages of using OOP is that it makes code more readable and maintainable. This is because you can break down your code into smaller modules, which makes it easier to understand and modify. Additionally, OOPs allows you to reuse components across different projects, which can make development faster and more efficient. Overall, I think that OOP is a great way to improve your development skills and increase your overall efficiency when working on software projects.

9. How Does Use OOP Benefit You?

There are many benefits to using object-oriented programming (OOP). Some of the top benefits include:

  • Improved Structured Programming

OOP allows for better-structured programming because classes can be used to define the structure of data and relationships between data. This makes it easier to understand the code and maintain it.

  • Increased Efficiency

OOP allows for more efficient use of resources because objects can be created and controlled independently. This means that fewer resources are required to carry out a task, which can save time and money.

  • Enhanced Software Quality

OOP is often used in conjunction with unit testing and other quality assurance measures, which result in higher-quality software.

  • Easier Integration with Other Applications

OOP often makes it easier to integrate programs with other applications, which can reduce the time needed to create cross-platform solutions.

10. OOP Inheritance Types

When preparing for an Object-Oriented Programming Interview, one of the most important concepts to understand is inheritance. Inheritance can be broken down into two types: direct and indirect.

Direct inheritance occurs when one class directly inherits properties and methods from another class. For example, class A might have a property called b that is a member of class B. A would then be considered to have a direct inheritance from B, meaning that A would have access to all the properties and methods of B.

Indirect inheritance occurs when one class inherits properties and methods from a base class, but not from any other classes. Class C might inherit from base class D, but not from E or F. In this case, C would have access to the properties and methods of both D and base class E, but not to those of F.

There are several benefits to using inheritance in your codebase. First, it allows you to easily reuse code by incorporating functionality from other classes into your own. Second, it makes it easy to create hierarchies of classes, which makes it easier to manage your codebase complexity.

11. OOP, Why Are They So Popular?

Object-Oriented Programming (OOP) is a programming paradigm that emphasizes the structure of a program as well as its data. This makes it easier to read, understand, and maintain code. OOPs, are also popular because they allow multiple developers to work on the same project without accidentally affecting each other’s code.

12. OOP Has Some Advantages, What Are They?

I’ve been asked this question in an interview. The main advantage of using OOP is that you can modularize your code and make it easier to read, maintain, and extend. In addition, OOP allows for code reuse and collaboration between different developers.

13. How Can OOP Define Overriding And Overloading?

When I was preparing for my Object Oriented Programming Interview, I realized that overloaded and overriding are important concepts in OOP. Overloading is when a function takes more than one argument. Overriding is when a function replaces another function in the same class. This allows different parts of the code to do different things, depending on what type of data is passed in. For example, let’s say you have a function that takes an integer and prints it out. You could overload the function so that it takes a string as well. This would allow the code to print out “2”, “3”, and “5” without having to change the function name or create a new function.

14. OOP Has What Limitations?

Given that I am interviewing for a position in a company that specializes in Object-Oriented Programming (OOP), I was eager to learn more about this programming paradigm. After reading some articles on the subject, I realized that OOP has its limitations. For example, OOP is not always the best solution for certain problems. For instance, when it comes to creating user interfaces, OOP can be cumbersome and inefficient. Additionally, OOP can be difficult to learn and apply, especially if you are not familiar with the basic concepts of computer programming. Overall, I think OOP is a powerful tool, but it should not be relied on exclusively.

15. In The World Of OOP, What Is Garbage Collection?

In the world of Object-Oriented Programming, garbage collection is a process that helps to free up memory by reclaiming unused objects. It’s a key part of keeping applications running smoothly, and it can be a real challenge for new programmers.

16. In Object-Oriented Programming, What Is Polymorphism?

Polymorphism is a term used in object-oriented programming that refers to the ability of an object to behave differently depending on the particular instance or class of instance it is used in. This can be helpful in developing code that is more flexible and easier to maintain.

I understand polymorphism when it comes to classes, but what about functions? Functions are objects too, right? Functions can also be polymorphic, yes. However, they aren’t as commonly used because they’re not as flexible. Functions can also be polymorphic when it comes to returning types, but this isn’t as common because it can lead to confusion.

17. In OOP, How Does The Copy Constructor Work?

I understand that the Copy Constructor is used to create an object from another object. It is important to remember that the Copy Constructor will always create a new object, so you can’t use it to copy an existing object.

18. Object-Oriented Programming Is Based On Inheritance. What Is It?

In object-oriented programming (OOP), inheritance is a feature that allows one class to inherit the properties and methods of another class. This can be useful for creating more reusable code, as well as for improving code organization.

19. What Is Hybrid Inheritance?

Hybrid inheritance is a technique that allows you to inherit some of the behavior of an object from another object. This can be useful if you want to reuse code that has been written for an object without having to copy the entire object.

20. Explain How To Override Methods In OOP

Once I had a good understanding of the code, I began to think about how I would solve the problem. In most cases, overriding a method means replacing one implementation of the method with another. However, there are times when you have to provide your own implementation of a method, which is known as providing your own implementation of an abstract method. In these cases, you have to provide your own implementation of the abstract method as well as the specific methods that you want to override.

21. A Virtual Function In OOP Is What?

Virtual functions are a feature of object-oriented programming languages that allow a function to be called by name, even if the function has not been defined yet. This is useful for creating temporary functions that can be used in different places in your program.

22. In OOP, Explain The Different Types Of Inheritance

When I was interviewing for my current programming job, one of the questions they asked me was what kind of inheritance I knew. I had never heard of it before, so I did some research and found out that there are three types of inheritance: classical, partial, and composition. Classical inheritance is when a class inherits all the properties and methods from another class. Partial inheritance is when a class inherits part of the properties and methods from another class. Composition is when a class combines the features of two or more other classes into itself.

After learning about these different types of inheritance, I realized that I would be better suited for a position that required me to know classical inheritance because that’s what my current job requires. However, knowing about partial and composition inheritance was helpful because it showed me that I could handle working with multiple classes simultaneously if needed.

Overall, I learned a lot about OOP during my research and interview process and appreciate the different types of inheritance that are available to programmers.

23. The Object-Oriented Programming Model Is Used By Some Programming Languages. What Are These Languages?

When I was interviewing for a programming job, the interviewer asked me which programming languages were based on the Object-Oriented Programming model. I knew that Java, Python, and Ruby were all languages based on the Object-Oriented Programming model, but I didn’t know what the others were.

After some research, I learned that Java is based on the “Object-J” model, Python is based on the “Pythonic” model, and Ruby is based on the “Ruby on Rails” model.

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24. How Does OOP Reuse Work?

The concept of inheritance is used as a reuse mechanism in object-oriented programming. Inheritance allows a class to inherit the properties and methods of another class, thus creating a new type of class. This is beneficial because it allows classes to be reused in different situations without having to write the same code twice.

25. Does The OOP Concept Expose Only The Necessary Information To The Function Calling It?

I was doing an interview for a programming position and the interviewer asked me about OOP concepts. One of the concepts he asked me about was hiding the necessary information from the calling functions. He was asking if I knew about the concept of hiding members. When I first heard the question, I didn’t know what he was talking about. After some research, I found that this is actually an OOP concept called encapsulation.

When you create a function, you want to make sure that only the necessary information is exposed to the caller. This is done by hiding member variables and functions from view. By doing this, you can keep your code clean and organized while still allowing the caller to access what they need. This is an important concept when it comes to writing good code, as it allows other developers to work more easily with your codebase.


At first, I was really nervous about my Object Oriented Programming (OOP) interview. I had read all the books and practiced for weeks, but I didn’t know what to expect. When the time arrived, I walked into the interview room and sat down across from my interviewer. She looked at me inquisitively and asked me to explain a problem that I solved using OOP techniques. By the time I was finished, it felt like she already knew everything about me and my skills, it was pretty disconcerting!