TCS interview questions and process for freshers

How the TCS interview usually goes

Based on what candidates commonly report. The process changes by year, role and campus, so always check the official TCS careers page and your drive's notification.

1. 1

   Online test (TCS NQT)

   Most freshers start with the TCS National Qualifier Test, an online test that commonly covers numerical ability, reasoning, verbal ability and programming or coding. Your performance typically decides which hiring track you are considered for (TCS has used names such as Ninja, Digital and Prime).

2. 2

   Technical interview

   Often covers your project, the language you listed, OOP, DBMS and SQL, and sometimes a short program to write or explain. Candidates for higher tracks commonly report more coding and problem solving.

3. 3

   Managerial round

   Situational and teamwork questions, how you handle pressure, and sometimes more technical questions.

4. 4

   HR round

   Background, relocation and shifts, and documents. Candidates often report the technical, managerial and HR rounds happening in one sitting with a panel.

Technical questions freshers are commonly asked

TCS technical interviews for freshers usually stay on fundamentals: your project, one programming language, OOP, DBMS and SQL, and some OS and networking basics, plus a short program to write or explain. Clear, confident communication counts as much as depth.

1. Q1.

   Explain your final-year (or best) project.

   Cover the problem, your own part, the tech stack and why you chose it, one hard bug or decision, and what you would improve. Expect follow-ups on anything you name, so only list what you can defend.

2. Q2.

   What are the four pillars of OOP?

   Encapsulation (keeping data and the methods that use it together, and hiding internal state), abstraction (exposing what an object does, not how), inheritance (a class reusing and extending another) and polymorphism (one interface, many forms). Give a small example in the language you know best.

3. Q3.

   What is the difference between method overloading and overriding?

   Overloading is the same method name with different parameter lists, usually in the same class, and is resolved at compile time. Overriding is a subclass redefining a parent method with the same signature, resolved at runtime (runtime polymorphism).

4. Q4.

   Abstract class vs interface: when would you use each?

   An abstract class can hold fields, constructors and both abstract and concrete methods, and (in Java) a class can extend only one. An interface is a contract a class can implement many of; since Java 8 it can have default and static methods but no instance state. Use an abstract class for a shared base, an interface for a capability.

5. Q5.

   Why is Java called platform independent? What are JDK, JRE and JVM?

   Java source compiles to bytecode, which any JVM runs, so the same .class files work on any OS that has a JVM. The JVM runs bytecode, the JRE is the JVM plus the standard libraries needed to run programs, and the JDK adds the compiler and tools needed to develop them.

6. Q6.

   What is the difference between a primary key and a foreign key?

   A primary key uniquely identifies each row and cannot be NULL; a table has one. A foreign key is a column that refers to a primary (or unique) key in another table, enforcing referential integrity; it can repeat and, unless declared NOT NULL, can be NULL.

   SQL basics
7. Q7.

   What is normalisation? Explain 1NF, 2NF and 3NF.

   Normalisation organises tables to reduce duplicate data and update anomalies. 1NF: every column holds atomic values, no repeating groups. 2NF: 1NF and no non-key column depends on only part of a composite key. 3NF: 2NF and no non-key column depends on another non-key column (no transitive dependency).

8. Q8.

   Explain the types of SQL joins.

   INNER JOIN returns rows that match in both tables; LEFT JOIN returns every row of the left table plus matches (NULLs where none); RIGHT JOIN is the mirror; FULL OUTER JOIN returns all rows from both. A self join joins a table to itself, such as employees to their managers.

   Joins explained
9. Q9.

   Write a SQL query to find the second-highest salary.

   Take the maximum salary below the overall maximum. With window functions, DENSE_RANK() handles ties and generalises to the Nth highest.

   SELECT MAX(salary) FROM employees
   WHERE salary < (SELECT MAX(salary) FROM employees);

   Subqueries & CTEs
10. Q10.

    DELETE vs TRUNCATE vs DROP?

    DELETE removes rows (optionally with a WHERE clause) one by one. TRUNCATE removes all rows quickly without a WHERE clause. DROP removes the whole table, structure and data. Whether TRUNCATE can be rolled back depends on the database, so say that rather than guessing.

11. Q11.

    What is the difference between a process and a thread?

    A process is a running program with its own memory space. Threads run inside a process and share its memory (code, heap) while each has its own stack and registers, so they are cheaper to create and switch, but shared data needs synchronisation.

    Processes vs threads
12. Q12.

    What is a deadlock, and how can it be prevented?

    A deadlock is when two or more processes each wait forever for a resource the other holds. It needs four conditions together: mutual exclusion, hold and wait, no preemption and circular wait. Break any one, for example by always acquiring locks in the same order.

    Deadlocks
13. Q13.

    What is the difference between TCP and UDP?

    TCP is connection-oriented and reliable: it delivers data in order, retransmits lost packets and controls flow (web pages, email, file transfer). UDP is connectionless with no delivery guarantee but lower overhead (video calls, online games, DNS lookups).

    TCP vs UDP
14. Q14.

    What happens when you type a URL in the browser and press Enter?

    The browser resolves the domain to an IP address through DNS (checking caches first), opens a TCP connection (plus a TLS handshake for HTTPS), sends an HTTP request and gets a response. It then parses the HTML, fetches CSS, JavaScript and images, and renders the page.

    DNS
15. Q15.

    Reverse a string without using a built-in reverse function.

    Use two pointers at the start and end, swap the characters and move both inward until they meet: O(n) time. In languages with immutable strings (Java, Python) convert to a character array or list first.

    Two pointers from both ends
16. Q16.

    Check whether a string (or number) is a palindrome.

    Compare characters from both ends moving inward; stop at the first mismatch. For a number, reverse its digits and compare with the original. Ask whether case, spaces and punctuation should be ignored.

    Two pointers from both ends
17. Q17.

    Write a program to check whether a number is prime.

    Numbers below 2 are not prime. Otherwise check divisibility only from 2 up to the square root of n, because any factor larger than the root pairs with one smaller than it. That makes it O(√n).

18. Q18.

    Swap two numbers without a third variable.

    a = a + b; b = a - b; a = a - b; works but can overflow. The XOR version (a ^= b; b ^= a; a ^= b;) avoids overflow but fails if a and b are the same variable. In real code a temporary variable is clearer.

TCS HR interview questions

1. 1.

   Tell me about yourself.

   60 to 90 seconds: your degree, one or two projects or skills that fit the role, and what you want next. Don't read out your resume.

   Tell me about yourself
2. 2.

   Why should we hire you?

   Match two or three of your strengths to the role, each backed by proof such as a project, an internship or a result.

3. 3.

   What are your strengths and weaknesses?

   Pick a real strength with an example, and a real but non-critical weakness along with what you are doing to improve it.

4. 4.

   Why TCS?

   Be specific: its scale and range of domains, structured training for freshers, or a business unit that interests you. Avoid generic praise.

5. 5.

   Are you willing to relocate and work in shifts?

   Answer honestly. Services companies place freshers on projects in different cities and time zones; if you have a genuine constraint, say so politely.

6. 6.

   Where do you see yourself in five years?

   Talk about growing your skills and responsibility in a way that could plausibly happen at this company, not about leaving it.

7. 7.

   Tell me about a challenge you faced and how you handled it.

   Use STAR: the situation, your task, the actions you took and the result, with the focus on what you did.

   The STAR method
8. 8.

   Tell me about a time you disagreed with a teammate.

   Show that you listened, argued with facts and kept the team moving; end with what you learned.

   Conflict & teamwork
9. 9.

   Your branch isn't computer science. Why IT?

   Common for ECE, EEE and mechanical students. Show genuine interest with evidence: courses you took, programs or projects you built, and what you enjoy about software.

10. 10.

    Do you have any questions for us?

    Always ask one or two, for example about training, the team you would join, or what a good first year looks like.

    Questions to ask the interviewer

How to prepare for the TCS interview

1. 1.

   Clear the online test first

   The NQT comes first, and many candidates are filtered there. Practise aptitude a little every day with timed quizzes: percentages, profit and loss, time and work, number series and seating arrangements come up often.

   Aptitude practice
2. 2.

   Make practice a daily habit

   Five questions a day adds up. The Daily Quiz takes about three minutes and needs no login.

   Daily Quiz
3. 3.

   Revise core CS

   OOP, DBMS and SQL, operating systems and networking basics. Aim to explain each concept in two or three sentences with an example.

   Study notes
4. 4.

   Know your project inside out

   Your role, the tech stack and why, the database design, one problem you solved. Most fresher interviews spend a lot of time here.

5. 5.

   Write small programs by hand

   Strings, arrays and number programs (reverse, palindrome, prime, Fibonacci) in one language you know well, without an IDE, then trace them with an example.

6. 6.

   Practise speaking out loud

   Rehearse "tell me about yourself" and your project explanation. A TCS-style mock interview with Sam is a safe place to practise.

   Tell me about yourself
7. 7.

   Check the official details

   Eligibility rules, test patterns and hiring tracks change from year to year. Read the official TCS careers page and the drive notification for your batch.

Frequently asked questions