23 Top Computer Science Interview Questions & Answers [For Freshers & Experienced]

Getting a job in computer science can be quite challenging. There’s a lot of competition and recruiters always look for candidates that have a strong grasp of the subject. One of the most effective ways to prepare for a computer science interview is to prepare computer science interview questions and answers.

Apart from having a well-curated resume, one might not get their dream job solely due to the fact that they could not crack the interview! Moreover, oftentimes, not pre-planning and preparing for the interviews can lead to extreme anxiety and nervousness, which can affect their knowledge quotient and personality as well. Practicing random computer science questions will not be that fruitful.

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There is an abundance of basic computer science interview questions on the internet that can help someone prepare well for their dream job. There are also computer engineering interview questions and answers pdf available. However, most of the time, they are outdated and hence, do not serve the purpose. Therefore, searching for basic computer science questions and answers that are currently trending and making one’s own pdf can be more fruitful.

We have compiled a list of some of the most popular computer science interview questions. You can go through the list and prepare for your next computer science interview. Keep reading till the end to get a better idea of what to expect from the interviewer in a computer science interview, and create your own computer engineering interview questions and answers pdf to kickstart your preparation.

Now, let’s get started!

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Basic Computer Science Interview Questions 

Below are some detailed computer science interview questions and answers for freshers often asked in entry-level jobs.

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1. What is a Computer System?

Ans: A computer system is a combination of CPU, memory, and Operating System (OS) and supplementary devices connected to it (keyboard, mouse, speakers, etc.). 

2. What do you mean by a Microprocessor?

Ans: A microprocessor refers to an integrated circuit functioning as the central processing unit of a computer system. 

3. What are the Components of a Computer System? List Them. 

Ans: A computing system consists of the following components:

• Memory (primary and secondary).
• Central Processing Unit containing the control unit and the arithmetic-logical unit.
• Input and output devices such as a mouse, keyboard, printer, speakers, and more. 

4. Can You List Out Some Popular Operating Systems?

Ans: Microsoft Windows, Linux, and OSX are some of the most popular operating systems. 

5. What do you Mean by SDLC?

Ans: SDLC stands for Systems development life cycle or application development life cycle and is the process of creating, planning, deploying, and testing a system. It focuses on producing a software product efficiently. 

Read: Major Projects for Computer Science Students

6. List a Few Popular Computer Processors. 

Ans: Intel Core i9, Intel Core i7, Intel Core i5, AMD Ryzen 5, and AMD Ryzen 7 are some of the most popular computer processors. 

7. What is a Framework?

Ans: A framework is a platform that allows you to create software applications. It gives you the foundation on which you can create a program for a particular platform. It might consist of predetermined functions and classes. You can use a framework to manage the hardware, inputs, and work with the system software. 

These questions comprise a combination of computer science interview questions and answers for freshers as well as experienced candidates. Practicing these computer science basic questions will surely higher the probability of getting a couple of commons in the computer science interview questions.

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Challenging Computer Science Interview Questions 

8. What do you Mean by a File?

Ans: A file is a location that stores data and information. They are always located inside a storage device by using the name assigned to the same. They keep the information either permanently or until you delete it. They are a fundamental component of computer science. 

9. What do you mean by a Class and a Superclass? 

Ans: Class defines the features of an object like how it will respond to a message and what kind of a message the object will react to. A superclass is the basis of the class we consider. 

Also read:Learn Java Free!

10. What do you mean by a Chipset?

Ans: A chipset helps you in controlling the communication between different devices and is crucial for determining whether a computer system is functioning properly or not. It controls the communication between all the computer components such as the CPU, the storage, and the RAM.

It tells you which and how many USB devices your motherboard can support. Primarily, chipsets help a computer system in controlling peripheral components such as the keyboard, monitor, mouse, or printer. 

11. What is Inheritance in Computer Science?

Ans: Inheritance is a component in programming that we use frequently in computer science professions. It refers to the property that gets passed from a superclass to a subclass.

Additional Note: This is one of the most important computer science interview questions and answers. So be sure to prepare this question with extra caution.

12. What is a Destructor?

Ans: A destructure is a class member function for deleting or destructing objects. 

13. What is the Function of the Byte Stream?

Ans: We use the byte stream to implement input and output for Unicode with 8 bits. 

14. Can you Differentiate Between Method and Constructor?

Ans: There are plenty of differences between method and constructor. We use a method to perform some function whereas we use a constructor to initialize a class’s instance. The method has a return type while Constructor doesn’t have a return type. Moreover, the name of a method can be different or the same according to your requirements but the name of a constructor must always be the same as the class name. We must call the method explicitly and the compiler doesn’t provide any method. On the other hand, the constructor calls automatically when we make a class object and the compiler provides a default compiler. 

Also Read: Computer Science vs Computer Engineering

15. What do you Mean by a Programming Language?

Ans: A programming language is a formal language made up of instructions that can generate different types of output. We use programming languages to execute algorithms in computer programming and most of them are made of instructions for computer systems to perform. Some of the most popular programming languages include Python, Java, C, and C#. 

Advanced Computer Science Interview Questions 

16. What do you Mean by Cryptography? 

Ans: Cryptography, also known as cryptology, is the study and practice of techniques for secure communication. It focuses on studying techniques that prevent unwanted parties from accessing your information or communication. 

17. What do you Mean by an Algorithm?

Ans: An algorithm refers to a definite sequence of executable and well-defined instructions for solving a class of problems or performing a computation. 

18. What is WWW (World Wide Web)? 

Ans: The World Wide Web is an information system where web resources (such as documents) are accessible through the internet. Those resources can be interlinked by using hypertext and have Uniform Resource Locators (URLs) for identification. 

19. What do you Mean by the Internet?

Ans: The internet is a worldwide network of computers that allows you to access numerous communication and information facilities. In this system, the users at any computer system with the right permission, can get information from another computer system or interact with users of that system. 

20. What do you Mean by an Operating System?

Ans: An operating system, called OS in short, is software that interacts with the hardware and enables other programs to run. Every smartphone, tablet, and computer system has an operating system that offers the fundamental functionalities to the device. Popular operating systems include Linux, OS X, and Microsoft Windows. 

21. What is the Main Difference Between Thread and Process?

Ans: Thread is a section of a process whereas a Process is a program within the execution. A process can’t have multiple threads but vice versa isn’t possible. 

22. What is Primary Memory?

Ans: Primary memory is the central memory of a computer which you can access by using the Central Processing Unit (CPU). It contains information temporarily until the particular process completes its execution. 

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23. What is the Difference Between the Interpreter and Compiler?

Ans: There are plenty of differences between a compiler and an interpreter. First, there’s the difference in speed. Interpreted code runs slower than compiled code. The interpreter doesn’t produce an output program so you must evaluate the source while executing the code, whereas the compiler produces an output program as an exe file which you can run separately from the source.

The interpreter is most suitable for the development environment whereas it’s a little challenging to execute the compiler because you can’t predict what would happen at turn time. Moreover, the interpreter takes only one line of code as its input whereas the compiler takes the complete program as its input. 

The interpreter remains in the memory during interpretation. On the other hand, the compiler executes the target program separately and doesn’t have to remain in the memory for this process. Finally, the interpreter would show all the errors one-by-one while the compiler would show them all at once after completing the compilation. 

24. What are the Various Types of Access Modifiers?

Ans: There are four kinds of access modifiers: Default, Private, Public, and Protected. The private modifier makes the class (or method) visible to a specific class while the public modifier makes it visible to everything. The protected modifier would make it visible to particular packages. 

Practicing basic computer science interview questions, especially targeting particular job roles can be even more helpful. Below are some of the computer science basic questions asked in their interviews in the top job roles.

Software Developer

  1. What are the different categories of software?

The various categories of software include system software, embedded software, scientific software, artificial intelligence software, and networking and web development software.

  2. What is meant by a framework?

It is a set of tools that helps build or alter software. They are the basis of the software development process however, the information provided by frameworks is rather made on an abstract level than giving out exact details on how to perform software development.

  3. What makes computer programs and computer software different from each other?

Software is a compilation of several programs, whereas programs are made up of several instructions written in a programming language. Programs can be software, but the opposite is not true.

  4. Name some of the available SDLC models.

Some of the notable SDLC models include the Spiral model, waterfall model, agile model, big bang model, and incremental model.

  5. What is meant by debugging?

Debugging can be explained as the process of finding, evaluating, and correcting software problems popularly known as software bugs.

Database administrator

  1. What is meant by SQL, and what are some of the most common SQL queries used?

SQL is the short form for Structured Query Language. It is a programming language that is popularly used for modifying and accessing data in various databases. Some of the most commonly used SQL queries include CREATE, UPDATE, DELETE, INSERT, etc.

  2. Are T-SQL and PL/SQL the same? If not, then state the difference.

No, they are not the same. T-SQL is Transact-SQL, which is the extension of SQL used in Microsoft. Whereas PL/SQL is Procedural Language-SQL which is used in Oracle. Apart from this, they also vary in terms of difficulty in usage, integration potential, etc.

  3. What is the difference between navigational and relational databases?

Navigational databases access data by defying the path to find the needed data. On the other hand, in rational databases, one can access data by stating exactly what one wants. Unlike navigational databases, rational databases do not have hierarchical or network structures.

  4. What is meant by a join clause?

It is a feature in SQL that helps in simultaneous searches across multiple tables by combining two or more tables into one new table.

  5. What is the first and foremost step in dealing with a lost database?

The first and foremost step in dealing with a lost database includes restoring the most recent consistent state right before the database was corrupted.

Computer System Analyst

  1. What qualities should a computer system analyst possess?

A system analyst must have outstanding analytical thinking. Apart from that, they should be highly organized and knowledgeable regarding different technological systems. Their adaptability toward new technology should also be great, and they must also be good at communicating both written and verbally.

  2. Elaborate on the DHCP server.

DHCP stands for Dynamic Host Configuration Protocol, which is used for providing a quick, automatic, and centrally managed distribution of IP addresses within a network. DHCP is often used for configuring subnet mask, default gateway, or DNS server information.

  3. What are the types of requirements a system analyst gathers for analyzing?

There are two types of requirements that a system analyst should gather for analysis. Technical requirements refer to information regarding the build of the system, and functional requirements include details about the deliverables.

  4. State the difference between subnetting and super netting.

Subnetting can be described as the process of dividing a network into sub-networks, whereas super netting is the process of combining smaller networks together. Therefore, simply both are opposite to each other.

Web Developer

  1. State the reason why namespace is used in web Development.

Namespaces are a global object that holds various methods, properties, and other objects in them. Therefore, they help provide ease of use through modularity, allowing the user to reuse codes and avoid naming conflicts.

  2. How is Canvas used in HTML?

Canvas was included in HTML to give the users the benefit of doing graphic designing with the help of Javascript. Canvas consists of various methods that allow drawing circles, boxes, images, and many more.

  3. Mention the use of CORS.

CORS, or Cross-origin Resource Sharing, is a mechanism that helps in requesting a variety of resources from a domain that is outside the current request domain.

  4. Mention some of the types of CSS that are used.

A few types of CSS that are widely used include Inline CSS, External CSS, and Embedded CSS.

  5. Why is grouping used in CSS3?

The use of grouping in CSS3 allows users to reuse and apply the same CSS style elements to more than one HTM entity, also within one declaration statement.

Computer Hardware Engineer 

  1. Are you familiar with Heat Sink? How important it is?

Yes. It is utterly important as it helps in lowering the temperature of a computer or any device consisting of microprocessors. It is a piece of metal sitting on the top of a computer chip that helps absorb or dissipate unwanted heat.

  2. Why do microprocessors get overheated?

Overheating may cause due to varied reasons however, some of the most common ones include poor connection of the processor fan, dust build-up, too many applications running simultaneously, etc.

  3. What is the difference between the main memory and the chase memory of a computer?

The main memory stores the OS system software, software applications, and any other information. Whereas Cache memory is the memory area between RAM and the processor, which helps improve the speed of the system.

  4. How SCRAM and DRAM are different from each other?

SCRAM or static-RAM stores every single data on MOSFETs therefore, providing extremely fast data access without high capacity. Whereas DRAM or dynamic-RAM stores every bit of data in the transistor and capacitor, which has higher chances of losing data fast if not refreshed severally.

  5. What is the difference between multitasking and multiprocessing?

In multitasking, a processor performs several programs at once by switching between them. This process does not require multiple processors. Whereas in multiprocessing, a processor performs numerous functions and programs simultaneously with the help of several processors.

How to Prepare Computer Science Interview Questions and Answers?

Preparing for an interview can be quite cumbersome, we hope the above questions can help you with the same. We hope that you found our article on computer science interview questions and answers useful. Preparing these questions can certainly enhance your chances of bagging the job without any worries. 

Going through the various questions and answers can be a little challenging. If you want to become a computer science professional, we recommend taking a computer science course as well as practicing basic computer science questions and answers. It takes only a few months but helps you become an expert in computer science. For example, the course we shared covers all the basic aspects of computer science and lets you choose a specialization to learn the advanced aspects of the same.

The course comes with upGrad’s exclusive job assistance and learning support. We will help you prepare for interviews and learn from industry mentors to ensure you understand every aspect of the subject.

You get to learn multiple computer science topics such as software development and programming along with various technologies. 

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