Are you preparing for an interview with NTT Data? Whether you’re a fresher or an experienced professional, understanding the most commonly asked questions can give you a serious edge. In this comprehensive guide, we’ve compiled the Top 30 NTT Data Interview Questions and Answers (2025 Updated) to help you crack your next interview with confidence.
This list includes both technical and HR questions — handpicked based on recent interview patterns and real candidate experiences. From coding questions and OOPs concepts to SQL, Java, JavaScript, and behavioral questions, we’ve got it all covered.
If you’re searching for the NTT Data Interview Questions: Most Asked Technical & HR Questions, or want to know the 30 Most Frequently Asked Interview Questions at NTT Data, this is the perfect place to begin.
👉 Use this guide to:
- Understand how to structure your answers
- Prepare for different interview rounds
- Get real-world examples that interviewers love
1. Tell me about yourself.
Explanation: A common HR opening question to assess your introduction, confidence, and summary of background.
Example Answer:
“My name is [Your Name], and I recently completed my B.Tech in Computer Science Engineering from [Your College Name].
During my academic journey, I developed a strong foundation in data structures, algorithms, object-oriented programming, and web development. I’ve worked on a few academic and personal projects, including a [mention 1 project – e.g., “college management system using MERN stack”], which helped me improve my problem-solving and hands-on coding skills.
I’m particularly interested in full-stack development (or software development, machine learning, etc. – based on your interest) and I’ve also gained familiarity with tools like Git, VS Code, and basic cloud deployment.
Apart from academics, I’ve participated in coding contests and hackathons, which helped me learn teamwork and agile problem-solving.
I’m now looking for an opportunity to contribute to a dynamic tech team, grow my skills further, and build scalable, real-world solutions.”
2. What do you know about NTT Data?
Explanation: Tests your research and interest in the company.
Example Answer:
“NTT Data is a global IT services provider headquartered in Tokyo, Japan. It is part of the NTT Group and specialises in consulting, managed services, and business process outsourcing. They serve sectors like finance, healthcare, telecom, and automotive with innovative digital solutions.”
3. Explain OOPS concepts with examples.
Answer: Object-Oriented Programming (OOP) is a programming paradigm based on the concept of “objects”, which can contain data and code — data in the form of fields (attributes) and code in the form of methods (functions).
- Class: A class is a blueprint or template for creating objects.
Example in Java:
class Car {
String color;
int speed;
void drive() {
System.out.println(“Car is driving”);
}
}
- Object: An object is an instance of a class. It has state and behavior.
Example:
public class Main {
public static void main(String[] args) {
Car myCar = new Car(); // Object creation
myCar.color = “Red”;
myCar.drive();
}
}
- Encapsulation: Encapsulation is hiding internal details of an object and only exposing necessary parts through public methods (getters/setters).
Example:
class Student {
private int age;
public void setAge(int age) {
this.age = age;
}
public int getAge() {
return age;
}
}
- Inheritance: Inheritance is the process where one class acquires properties and methods of another class.
Example:
class Animal {
void sound() {
System.out.println(“Animal makes sound”);
}
}
class Dog extends Animal {
void bark() {
System.out.println(“Dog barks”);
}
}
- Polymorphism: Polymorphism allows one action to behave differently based on the object.
- a) Compile-time Polymorphism (Method Overloading):
class Calculator {
int add(int a, int b) {
return a + b;
}
double add(double a, double b) {
return a + b;
}
}
- b) Run-time Polymorphism (Method Overriding):
class Animal {
void sound() {
System.out.println(“Animal sound”);
}
}
class Cat extends Animal {
void sound() {
System.out.println(“Meow”);
}
}
- Abstraction: Abstraction means hiding complexity and showing only essential features.
Example using abstract class:
abstract class Shape {
abstract void draw();
}
class Circle extends Shape {
void draw() {
System.out.println(“Drawing Circle”);
}
}
4. Difference between overloading and overriding.
Explanation:
Feature | Method Overloading | Method Overriding |
Definition | Defining multiple methods with the same name but different parameters within the same class. | Defining a method in a subclass that has the same signature as a method in the superclass. |
Inheritance | Not required | Must involve inheritance (parent-child relationship) |
Parameters | Must be different (type/number/order) | Must be exactly the same as the method in superclass |
Return Type | Can be different | Must be the same or a subtype (covariant return type) |
Access Modifier | Can be anything | Can’t be more restrictive than the superclass method |
Static/Instance | Can be overloaded whether static or not | Only instance methods can be overridden |
Polymorphism Type | Compile-time polymorphism | Runtime polymorphism |
✔ Example in Java:
class Calc {
int add(int a, int b) { return a+b; } // overloading
double add(double a, double b) { return a+b; }
}
class AdvCalc extends Calc {
@Override
int add(int a, int b) { return a+b+1; } // overriding
}
5. What is final, finally, and finalize in Java?
Explanation:
- final: Keyword to restrict inheritance or modification.
Example: final int x=10; - finally: Block that executes regardless of exception in try-catch.
- finalize(): Method called by Garbage Collector before object destruction.
6. What is an interface?
Explanation: An interface defines a contract (methods) that implementing classes must follow. It supports multiple inheritance in Java.
Example:
interface Animal {
void eat();
}
class Dog implements Animal {
public void eat() {
System.out.println(“Dog eats”);
}
}
7. Difference between abstract class and interface.
Explanation:
Feature | Abstract Class | Interface |
Keyword | abstract class | interface |
Methods | Can have both abstract and concrete (defined) methods | All methods are abstract by default (till Java 7)Can have default, static, and private methods (Java 8+) |
Fields/Variables | Can have instance variables, constructors | Variables are public static final (constants) by default |
Multiple Inheritance | ❌ Not supported | ✅ Supported through multiple interfaces |
Constructors | ✅ Can have constructors | ❌ Cannot have constructors |
Access Modifiers | Can use private, protected, public | Only public or default |
Use Case | When you want to share base logic + enforce contract | When you only want to define a contract/behavior |
Inheritance Keyword | extends | implements |
Inheritance Limit | A class can extend only one abstract class | A class can implement multiple interfaces |
8. Explain REST API with example.
Explanation:
- REST stands for Representational State Transfer.
- A REST API is an architectural style that allows communication between client and server over HTTP by using standard HTTP methods (GET, POST, PUT, DELETE, etc.).
- It is stateless, scalable, and uses resources (identified by URIs) to perform operations.
Example:
Method | Description | Example URI |
GET | Read/fetch data | /users/1 |
POST | Create new resource | /users |
PUT | Update/replace existing resource | /users/1 |
PATCH | Partial update | /users/1 |
DELETE | Delete a resource | /users/1 |
9. Difference between GET and POST.
Explanation:
Feature | GET | POST |
Purpose | Used to retrieve data from the server | Used to send data to the server (e.g., form data) |
Data visibility | Data is sent in the URL (visible in address bar) | Data is sent in the request body (hidden from URL) |
Security | Less secure (data exposed in URL) | More secure (data not shown in URL) |
Length limitation | Limited by URL length (around 2048 chars) | No significant size limit (depends on server settings) |
Caching | Cached by browsers by default | Not cached by default |
Bookmarking | Can be bookmarked | Cannot be bookmarked (no URL parameters) |
Idempotent | Yes – same request = same result (safe) | Not always – may cause changes each time |
Use case | Search queries, fetching data | Submitting forms, uploading files, saving data |
10. What is a promise in JavaScript?
Explanation: A Promise in JavaScript is an object that represents the eventual completion (or failure) of an asynchronous operation, and its resulting value.
Example:
let promise = new Promise(function(resolve, reject) {
let success = true;
if (success) {
resolve(“Data fetched successfully”);
} else {
reject(“Failed to fetch data”);
}
});
promise
.then(function(result) {
console.log(result); // Output: Data fetched successfully
})
.catch(function(error) {
console.log(error); // If failed
});
11. Difference between == and === in JavaScript.
Explanation:
Operator | Name | Checks | Performs Type Conversion | Example Result |
== | Loose Equality | Value only | ✅ Yes | “5” == 5 → true |
=== | Strict Equality | Value and Type | ❌ No | “5” === 5 → false |
12. What is closure in JavaScript?
Explanation: A closure is a feature in JavaScript where an inner function has access to the outer (enclosing) function’s variables, even after the outer function has returned.
Example:
function outer() {
let count = 0;
return function inner() {
count++;
return count;
}
}
const c = outer();
console.log(c()); // 1
console.log(c()); // 2
13. Explain event delegation.
Explanation: Event Delegation is a technique in JavaScript where you assign a single event listener to a parent element, instead of adding it to each child element. This listener uses event bubbling to catch events from its child elements.
Why Use Event Delegation?
- Better performance (fewer event listeners)
- Dynamically handle future child elements
- Cleaner and more maintainable code
14. What is CSS specificity?
Explanation: CSS specificity determines which rule is applied to an element when multiple rules match. It’s like a scoring system that decides which selector “wins” in case of conflicts.
Why Is Specificity Important?
When you have multiple CSS rules targeting the same element, the one with the highest specificity is applied (unless overridden by !important).
Selector Type | Specificity Value |
Universal selector (*) | 0,0,0,0 |
Element/tag (div, h1) | 0,0,0,1 |
Class (.class) | 0,0,1,0 |
Attribute ([type=”text”]) | 0,0,1,0 |
Pseudo-class (:hover) | 0,0,1,0 |
ID selector (#id) | 0,1,0,0 |
Inline style (style=””) | 1,0,0,0 |
!important | Overrides everything |
15. Explain responsive design.
Explanation: Responsive design is a web development approach that ensures a website or application adapts smoothly to different screen sizes, devices, and orientations — whether it’s a mobile phone, tablet, laptop, or desktop.
Why Is Responsive Design Important?
- 📱 People use a variety of devices with different screen sizes.
- 🌐 Google prioritizes mobile-friendly sites in search rankings.
- ✅ One website works everywhere — no need for separate mobile sites.
16. What is RESTful routing?
Explanation: RESTful routing is a design pattern used in web development where the routes (URLs) are structured according to REST (Representational State Transfer) principles. It maps HTTP verbs (GET, POST, PUT, DELETE) to CRUD operations (Create, Read, Update, Delete) on resources (like users, products, posts, etc.).
Key Concepts of RESTful Routing:
HTTP Method | URL Pattern | Action | Description |
GET | /posts | Index | Get all posts |
GET | /posts/1 | Show | Get post with ID 1 |
POST | /posts | Create | Create a new post |
PUT | /posts/1 | Update | Update post with ID 1 |
DELETE | /posts/1 | Delete | Delete post with ID 1 |
17. What is middleware in Node.js?
Explanation: In Node.js, especially when using Express.js, middleware refers to functions that execute during the request-response cycle. These functions have access to the request (req), response (res), and the next() function, which passes control to the next middleware in the stack.
Purpose of Middleware
- Execute any code
- Modify the req and res objects
- End the request-response cycle
- Call the next middleware using next()
18. Difference between synchronous and asynchronous programming.
Feature | Synchronous Programming | Asynchronous Programming |
Execution | Code executes line by line, one after another | Code doesn’t wait for tasks to finish—continues executing |
Blocking | Blocking – Next line waits for previous to complete | Non-blocking – Doesn’t wait, continues with next task |
Performance | Slower for I/O or long tasks | Faster and more responsive |
Use Case | Simple scripts, calculations | Network requests, APIs, file reads, database calls |
Code Style | Straightforward, easier to follow | Requires callbacks, promises, or async/await |
19. What is callback hell?
Explanation: Callback Hell refers to a situation in JavaScript where multiple nested callbacks are used, making the code hard to read, debug, and maintain. It’s also called the “Pyramid of Doom” due to the deeply indented, triangular code structure.
Example of Callback Hell
doSomething(function(result1) {
doSomethingElse(result1, function(result2) {
doAnotherThing(result2, function(result3) {
doFinalThing(result3, function(finalResult) {
console.log(‘Done!’, finalResult);
});
});
});
});
20. What is a constructor?
Explanation: A constructor is a special method in a class that is automatically called when an object of that class is created. It is mainly used to initialize objects.
Key Characteristics:
- Has the same name as the class.
- Doesn’t have a return type (not even void).
- Called automatically when an object is created.
- Can be overloaded (multiple constructors with different parameters).
21. Difference between Array and Linked List.
Feature | Array | Linked List |
Memory Allocation | Contiguous (fixed-size block) | Non-contiguous (each node points to next) |
Size | Fixed at the time of declaration | Dynamic (can grow or shrink at runtime) |
Access Time | O(1) – Direct access via index | O(n) – Traversal required |
Insertion/Deletion | Costly (may involve shifting elements) | Efficient (adjust pointers) |
Memory Usage | Less (no overhead for links) | More (extra space for pointer) |
Cache Performance | Better (stored together) | Poorer (nodes may be scattered in memory) |
Implementation | Simple | Slightly complex |
Reverse Traversal | Difficult (needs loop/indexing) | Easy with doubly linked list |
22. Explain normalization in DBMS.
Explanation: Normalization is the process of organizing data in a database to eliminate redundancy (duplicate data) and ensure data integrity. It involves dividing large tables into smaller ones and defining relationships between them using foreign keys.
Why is Normalization Important?
- Removes data redundancy
- Avoids update, insert, and delete anomalies
- Ensures data consistency
- Improves database efficiency and clarity
Types (Forms) of Normalization
Normal Form | Rule | Example Fix |
1NF (First Normal Form) | Eliminate repeating groups — each cell must contain atomic (single) values. | Split multi-valued columns into separate rows. |
2NF (Second Normal Form) | Meet 1NF + move partial dependencies to separate tables. (Applies to composite keys) | Create separate tables for entities. |
3NF (Third Normal Form) | Meet 2NF + remove transitive dependencies (non-key → non-key). | Remove derived or indirectly related data. |
BCNF (Boyce-Codd Normal Form) | Stronger version of 3NF — every determinant must be a candidate key. | More strict on dependencies. |
23. What is ACID property in DBMS?
Explanation: The ACID properties are a set of key principles that ensure reliable and consistent database transactions in a Database Management System (DBMS). The term ACID stands for: Atomicity, Consistency, Isolation, Durability
Atomicity — “All or Nothing”
- A transaction is treated as a single unit of work.
- Either all operations in the transaction are performed or none are.
- If any part of the transaction fails, the entire transaction is rolled back.
Consistency — “Valid State → Valid State”
- Ensures the database remains in a valid state before and after a transaction.
- A transaction brings the database from one consistent state to another.
- Rules like constraints, foreign keys, triggers must still hold true.
Isolation — “No Interference”
- Ensures concurrent transactions do not affect each other’s execution.
- Changes made by one transaction are not visible to other transactions until committed.
Durability — “Permanent Results”
- Once a transaction is committed, the changes are permanently stored, even if the system crashes.
- The database guarantees the survivability of committed transactions.
24. What is indexing in SQL?
Explanation: Indexing in SQL is a technique used to speed up the retrieval of rows from a table. An index is like a book’s table of contents — it helps the database locate data faster, without scanning the entire table.
Without an index, when you run a query, the database engine must scan every row (called a full table scan) — which is slow for large tables.
With an index, the database can quickly jump to the relevant data using pointers.
Query:
CREATE INDEX idx_department ON Employees(department);
25. Write SQL query to fetch second highest salary.
Example:
SELECT MAX(salary) FROM employees
WHERE salary < (SELECT MAX(salary) FROM employees);
26. What is join? Types.
Explanation: A JOIN is used in SQL to combine rows from two or more tables based on a related column between them — usually using primary and foreign keys.
INNER JOIN
- Returns only the matching rows from both tables.
- Most commonly used JOIN type.
SELECT Orders.order_id, Students.name
FROM Orders
INNER JOIN Students
ON Orders.student_id = Students.student_id;
📎 Only students who have placed an order will be shown.
LEFT JOIN (or LEFT OUTER JOIN)
- Returns all rows from the left table, and matched rows from the right table.
- If there’s no match, NULLs are returned from the right side.
SELECT Students.name, Orders.order_id
FROM Students
LEFT JOIN Orders
ON Students.student_id = Orders.student_id;
📎 Shows all students, even if they haven’t placed any orders.
RIGHT JOIN (or RIGHT OUTER JOIN)
- Returns all rows from the right table, and matched rows from the left table.
- If there’s no match, NULLs are returned from the left side.
SELECT Students.name, Orders.order_id
FROM Students
RIGHT JOIN Orders
ON Students.student_id = Orders.student_id;
📎 Shows all orders, even if no matching student is found (rare but possible).
FULL JOIN (or FULL OUTER JOIN)
- Returns all rows when there is a match in one of the tables.
- Includes unmatched rows from both tables with NULLs.
SELECT Students.name, Orders.order_id
FROM Students
FULL OUTER JOIN Orders
ON Students.student_id = Orders.student_id;
📎 Shows all students and all orders, matched or not.
27. What is the primary key and foreign key?
Primary Key
- A Primary Key is a column (or set of columns) that uniquely identifies each record in a table.
- It cannot contain NULL values and must hold unique values.
- Each table can have only one primary key.
CREATE TABLE Students (
student_id INT PRIMARY KEY,
name VARCHAR(50),
age INT
);
Here, student_id is the Primary Key — it uniquely identifies every student.
Foreign Key
- A Foreign Key is a column (or set of columns) in one table that refers to the Primary Key of another table.
- It is used to maintain referential integrity between two tables.
- It can contain duplicate and NULL values.
CREATE TABLE Orders (
order_id INT PRIMARY KEY,
student_id INT,
order_date DATE,
FOREIGN KEY (student_id) REFERENCES Students(student_id)
);
Here, student_id in the Orders table is a Foreign Key referencing the student_id (Primary Key) in the Students table.
28. Why should we hire you?
Example Answer:
“As a fresher, I may not have industry experience yet, but I bring a strong foundation in programming, problem-solving, and computer science fundamentals, which I have built during my B.Tech in Computer Science.
I am a quick learner, highly motivated, and eager to grow. I’ve also worked on small projects, participated in hackathons and online coding challenges, which helped me apply my knowledge practically.
I am adaptable, open to feedback, and passionate about contributing meaningfully to your team. Given the opportunity, I will bring energy, a strong work ethic, and a willingness to go the extra mile to deliver results and grow with the organization.”
29. Where do you see yourself in 5 years?
Example Answer:
“As a fresher, my immediate goal is to join a reputed company like yours, where I can learn, grow, and build a strong foundation in real-world software development.
Over the next 5 years, I see myself becoming a technically skilled and dependable team member, contributing to challenging projects, continuously improving my skills, and maybe even taking on team leadership or specialized roles like full-stack developer, DevOps engineer, or cloud architect — depending on the direction my interests and strengths develop.
I’m also eager to keep up with new technologies and trends, and possibly work toward certifications or advanced roles that align with both my passion and the company’s vision.”
30. Do you have any questions for us?
Example:
“What are the potential career growth paths for someone starting at an entry-level position in your company?”
Shows you’re thinking beyond just getting the job — you’re interested in building a career.
Cracking an interview at a top company like NTT Data requires more than just technical knowledge — it takes clarity, confidence, and the ability to explain your ideas well. This list of the Top 30 NTT Data Interview Questions and Answers (2025 Updated) was designed to prepare you for the most expected questions across various domains.
Whether you’re reviewing the 30 Most Frequently Asked Interview Questions at NTT Data or brushing up on the most asked technical and HR questions, this guide is a powerful tool to help you succeed.
🔍 Final tips:
- Practice answering out loud
- Customize answers based on your projects
- Be ready for follow-up questions on every topic
We hope this guide helps you move one step closer to your dream role at NTT Data.
💼 Good luck — you’ve got this!
👉 Explore related interview guides to level up your preparation:
- Top Interview Questions : Your Ultimate Guide to Crack Any Coding Interview
- Top 25 HR Interview Questions and Best Answers
- Top 30 Technical Interview Questions Every Software Developer Should Know
- Top Questions Asked in Interviews – Be Ready to Impress!
- Top Interview Questions and Answers to Crack Your Next Job Interview