35+ Important Interview Questions & Answers for Computer Science

Frequently asked interview questions & answers for Computer Science jobs. 

A lot of people are extremely keen to take up a job in the field of IT / Computers as it matches their area of interest and they see a good career for themselves in this field. For them, the key is to have in-depth knowledge pertaining to the subject of IT. They have to prepare in the right fashion. These candidates have to predict a list of frequently asked questions and prepare the answers accordingly. 

If it is your dream job then you have to put in a lot of effort to make sure that you are up there with the best. If you are wondering how to crack the 2020 Computer Science interview or for that matter other jobs related to such fields then you have to first up acknowledge that every Computer Science interview is different. You cannot take things for granted. A lot of hard work, preparation, and research goes into it. 

This article will help you to understand the various questions that you might be subjected to when you appear for such jobs. The most common Computer Science interview questions with their answers have been incorporated in this article. Go through this article, it will help you immensely to prepare for such jobs.

35+ Important Interview Questions & Answers for Computer Science 

What is a  computer system?

A computer system may be described as a set of integrated devices meant for input, output, process, store data, or information. It can also be regarded as a combination of memory, CPU, peripheral devices that are connected to it, and OS (Operating System).

What is a microprocessor according to you?

A microprocessor is an electronic component that is used by a computer to do its work. A microprocessor is an integrated circuit having all the functionality of a central processing unit of a PC.

Mention some popular operating systems?

Some popular operating systems are Microsoft Windows, OSX, and Linux, Apple macOS, Android, and Apple iOS.

Name some key computer processors?

Some key Computer processors are as follows: 

• Intel Core i9.
• Intel Core i5.
• Intel Core i7.
• AMD Ryzen 7.
• AMD Ryzen 5.

Mention the components of a computer system?

The components of a computer system are as follows :

• Central Processing Unit ( CPU ) including the control unit as well as Arithmetic Logical Unit.
• Memory including Primary & Secondary.
• Input & output devices. Eg. Mouse, Keyboard, scanner, printer etc.

What is  SDLC? Mention the various stages of SDLC? 

SDLC stands for Software Development Life Cycle. It can be explained in simple terms as a process that produces quality software products in less time.

It involves 5 Stages.

• Planning.
• Design.
• Construction.
• Testing.
• Deployment.

Explain what is a File?

A file is a named location that stores information or data permanently. It is always stored in the storage device using a file name with primary and secondary names, which is separated by a "."(DOT).

What do mean by Integrated Development Environment?

It can be described as a software application that provides comprehensive facilities to computer programmers for developing software.

OR

An IDE is a GUI-based software program. It is designed to assist the programmers to build applications with all the needed programs and libraries.

What Is A Super-class?

It is basically a class from which many subclasses can be created.

A superclass is the basis of all the classes. The object of the rest of the class has all the characteristics related to the superclass.

Explain Framework?

It is basically a platform for making software applications. The basis required to build programs for a specific platform is provided by the framework to the developers. 

It can include predetermined classes and functions too. It can be used for the purpose of processing inputs, interact with the system software, and also for managing hardware. 

What do you know about  Artificial Intelligence?

Artificial Intelligence or machine intelligence is a term that is used to build smart machines capable of performing various tasks. The main aim of AI is to solve problems in a way that are better and faster.

It is basically the intelligence demonstrated by machines. 

What is machine learning in your opinion?

Machine Learning is a system that can learn from an excellent example through self-improvement and without being explicitly coded by a programmer. It basically focuses on the development of computer programs that can use data and learn from it.

What do you know about deep learning?

Deep learning is computer software that mimics the network of neurons in a brain. It is a subset of machine learning and is called deep learning because it makes use of deep neural networks.

How would you describe a class variable?

Variables represent a memory of class, which it shares with each and every instance. A class variable is any variable declared with the static modifier of which a single copy exists. 

What is a programming language?

It is a formal language comprising a set of instructions that produces various types of outputs.

 OR

A programming language is a collection of grammar rules for giving instructions to computers or computing devices in order to perform achieve and tasks.

Explain class?

A class is a blueprint for creating objects. A class contains methods and variables which are a class instance. It is an extensible program code template for creating objects.

Mention the types of constructors?

The two types of constructor are as follows:

1. Parameterized constructor 
2. Default constructor.

Mention the various  OOPS principles?

The basic OOPS principle has been stated below:

• Encapsulation, 
• Abstraction, 
• Inheritance and 
• Polymorphism.

Explain Interface?

The interface is similar to a class in Java, but it is a collection of abstract methods. They are similar to protocols. A class can have more than one interface.

What do you mean by destructor?

Destructor is a class member function that deletes or destructs an object.

What do you know about the byte stream?

The byte stream is most usually used to perform input and output for Unicode having 8 bits. It is an ordered sequence of bytes.

Name the various Layers of the OSI Model?

They are as follows:

• Physical.
• Application.
• Presentation.
• Session.
• Transport. 
• Network.
•  Data Link Layer.

What are the different OOPS principles?

The basic OOPS principle is stated below:

• Encapsulation
• Abstraction
• Inheritance
• Polymorphism

What is the primary difference between process and thread?

Process is called as a program which is in execution. Thread is a segment of a process, so a process can have more than one thread.

What is primary memory?

In a Primary memory, RAM is the main memory of a computer which can be directly accessed by the Central Processing Unit (CPU). It stores temporary information until the process finishes its execution.

What are the primary components of a computer system?

As a computer science professional, being able to accurately answer this question is important to ensure you convey a basic understanding of computers.

For example: The central processing unit, the memory, and the input and output devices are usually considered as the primary components of a computer system. The CPU is typically an arithmetic logic unit, control unit, or both. The memory of a computer system relates to both the primary and secondary memory."

What do you mean by cryptography?

It is a method by virtue of which information and communication is protected using codes. This is done to ensure that the information can be read and processed only by those for whom it is intended.

What do you mean by the internet?

The internet is a global network of a computer that offers a wide range of information and communication facility. It involves interconnected networks, using a communication protocol.

How would you explain inheritance?

Inheritance is a key component as far as computer programming is concerned and may be considered as a frequently asked question in most of the computer science job interview.   This question may be asked during the course of the interview to check out whether the candidate understands and know how to properly use inheritance in computer programming.

Example: "Inheritance is the property that has been passed on from a superclass to a subclass."

What do you mean by the World Wide Web (WWW)?

WWW or World Wide Web is a method of accessing information using internet media.

What is an Algorithm?

An algorithm is a rule or step-by-step process that must be followed in order to solve a particular problem.

Explain the operating system?

The main function of an Operating system is to act as an interface between the end-user & computer hardware. It is mandatory that each computer must have at least one Operating system to run other programs.

What do you mean by a chipset?

When it comes to controlling communications between devices then a chipset comes into play. It assist a computer professional in determining whether a computer system is functioning/performing properly.

A computer's chipset is something that controls the communication between all computer components which includes the RAM, CPU, and storage. The chipset denotes which and how many USB devices and high-speed components a motherboard can support. Chipsets are usually used to control peripherals like the mouse, monitor, and keyboard.

What is an operating system? What are the popular operating systems used today?

The interviewer will try to figure out whether the candidate knows about the operating system as well as the types of operating systems that are in use nowadays in a business setting. For a computer professional it is extremely important to know about the same in detail.

"An operating system helps computer software to communicate with computer hardware. The operating system supports a computer's basic functions and enables the user to perform various tasks. Key operating systems are Microsoft Windows, OSX, and Linux."

What is the difference between primary and secondary memory?

First up, we have to acknowledge the fact that we must have a thorough knowledge of Primary & Secondary memory. For any computer science position, it is mandatory to have in-depth knowledge about both Primary & Secondary memory as well as how they work and what's the major difference between them.

"Primary memory is considered as the main memory of a computer that can be accessed via the CPU. Semiconductor chips are commonly used technology for primary memory.

The secondary memory is basically an external storage device. It can be used to keep data and information permanently. Examples of secondary memory are floppy disks, USB flash drives, Hard drives.

What are the commonly used computer processors?

There is a strong possibility that the interviewer may like to know from the candidates about the various types of commonly used processors. The interviewer may be keen to know from the candidates about certain computer processors that are being used for carrying out the work the candidate has applied for.

As a candidate, you need to know the same & answer properly.

Some of the latest and most commonly used computer processors are as follows:

1)  Intel Core i5

2) Intel Core i7 

3)  Intel Core i9

4)  AMD Ryzen 5 

5) AMD Ryzen 7.

What is a constructor?

It can be regarded as a special type of subroutine called to create an object.

It is important to know how does a constructor works especially for a computer science professional.

Depending on the type of company you have applied to work at as well as the nature of the job, the interviewer will ask you about constructors and why they are considered relevant in computer science.

Conclusion

This article will help the candidates to get a fair bit of idea about the types of questions that may be asked during interviews. We have incorporated some key questions with their answer. It is recommended that apart from going through these important questions & answers, one must use other reference books to get a better grasp. These questions & answers will surely help the candidates, but they must go into details of every topic relevant to their job and interview.

If you have any suggestions or if you want such posts more frequently then kindly comment in the comment section.

Hope you all will find the above-stated questions and answers beneficial.

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Uses of Computers in Business- its Advantages and Disadvantages

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