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GATE 2021 Computer Science and Information Technology(CS) Syllabus, Preparation Tips and Books

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Nikkil Visha

Exams Prep Master | Updated On - Apr 8, 2021

GATE 2021 Syllabus for CS: Computer Science and Information Technology syllabus is based on the topics of graduation level which is further divided into 10 major sections. Out of these 10 sections, section 1 is entirely based on the topics of Engineering Mathematics.

  • In GATE 2021 CS paper, 72% of the syllabus is from Core Engineering Syllabus or subject syllabus, 13% of Engineering Mathematics, and 15% of General Aptitude. 
  • One must note that all GATE 2021 papers will have General Aptitude as a compulsory section. The paper will consist of 65 questions worth 100 marks. Check GATE 2021 CS Exam Pattern
  • Candidates are also eligible to appear for a maximum of 2 papers. Also, if you are in the 3rd year of graduation you can easily apply for the exam as the eligibility criteria has been revised for this year. Read More
  • This year GATE 2021 Computer Science and Information Technology syllabus has been revised and if you have opted for CS as your first paper then for the second paper you can appear only for MA. 

Every year lakhs of students appear for GATE Computer Science and Information Technology paper to get admission to the Postgraduate program in well-known Engineering Colleges of India like IITs, NITs, etc. If you will be able to clear GATE Cutoff then you will also eligible for the recruitment of various PSUs. Read the article to know more about the syllabus of computer science, weightage of important topics, preparation tips, and much more. 

Must Read: 

GATE Computer Science Syllabus

GATE 2021 Computer Science and Information Technology Syllabus

Candidates who appear for the exam must go through the GATE Computer Science and Information Technology syllabus to score better in the exam. CS syllabus is divided into 10 section as given below:

Section 1 – Engineering Mathematics

Sections Topics
Discrete Mathematics Propositional and first order logic. Sets, relations, functions, partial orders and lattices. Monoids, Groups. Graphs: connectivity, matching, coloring. Combinatorics: counting, recurrence relations, generating functions.
Linear Algebra Matrices, determinants, system of linear equations, eigenvalues and eigenvectors, LU decomposition.
Calculus Limits, continuity and differentiability. Maxima and minima. Mean value theorem. Integration.
Probability Random variables. Uniform, normal, exponential, poisson and binomial distributions. Mean, median, mode and standard deviation. Conditional probability and Bayes theorem.

Section 2 – Digital Logic

Sections Topics
Section 1 Boolean algebra. Combinational and sequential circuits. Minimization.
Section 2 Number representations and computer arithmetic (fixed and floating point).

Section 3 – Computer Organization and Architecture

Sections Topics
Section 1 Machine instructions and addressing modes. ALU, data‐path and control unit. Instruction pipelining, pipeline hazards.
Section 2 Memory hierarchy: cache, main memory and secondary storage; I/O interface (interrupt and DMA mode).

Section 4 – Programming and Data Structures

Sections Topics
Section 1 Programming in C. Recursion. Arrays, stacks, queues, linked lists, trees, binary search trees, binary heaps, graphs.

Section 5 – Algorithms

Sections Topics
Section 1 Searching, sorting, hashing. Asymptotic worst case time and space complexity. Algorithm design techniques: greedy, dynamic programming and divide‐and‐conquer.
Section 2 Graph traversals, minimum spanning trees, shortest paths

Section 6 – Theory of Computation

Sections Topics
Section 1 Regular expressions and finite automata. Context-free grammars and push-down automata. Regular and contex- free languages, pumping lemma. Turing machines and undecidability.

Section 7 – Compiler Design

Sections Topics
Section 1 Lexical analysis, parsing, syntax-directed translation. Runtime environments. Intermediate code generation.
Section 2 Local optimisation, Data flow analyses: constant propagation, liveness analysis, common subexpression elimination.

Section 8 – Operating System

Sections Topics
Section 1 System calls, processes, threads, inter‐process communication, concurrency and synchronization.
Section 2 Deadlock. CPU and I/O scheduling. Memory management and virtual memory. File systems.

Section 9 – Databases

Sections Topics
Section 1 ER‐model. Relational model: relational algebra, tuple calculus, SQL.
Section 2 Integrity constraints, normal forms. File organization, indexing (e.g., B and B+ trees). Transactions and concurrency control.

Section 10 – Computer Networks

Sections Topics
Concept of layering OSI and TCP/IP Protocol Stacks; Basics of packet, circuit and virtual circuit-switching;
Data link layer framing, error detection, Medium Access Control, Ethernet bridging; Routing protocols: shortest path, flooding, distance vector and link state routing; Fragmentation and IP addressing, IPv4, CIDR notation,
-- Basics of IP support protocols (ARP, DHCP, ICMP), Network Address Translation (NAT); Transport layer: flow control and congestion control, UDP, TCP, sockets; Application layer protocols: DNS, SMTP, HTTP, FTP, Email.

Direct link to download GATE Computer Science and Information Technology (CS) syllabus PDF 

Weightage of Important Topics

GATE 2021 Computer Science and Information Technology Syllabus: Weightage of Topics 

  • Sample Question 1: A court is to a judge as _____________ is to a teacher.
  • Sample Question 2: Ten friends planned to share equally the cost of buying a gift for their teacher. When two of them decided not to contribute, each of the other friends had to pay Rs 150 more. The cost of the gift was Rs. ____?
  • Sample Question 3: A certain processor uses a fully associative cache of size 16 kB. The cache block size is 16bytes. Assume that the main memory is byte-addressable and uses a 32-bit address. How many bits are required for the Tag and the Index fields respectively in the addresses generated by the processor?
  • Sample Question 4: In 16-bit 2’s complement representation, the decimal number −28 is?

We are providing you previous year analysis to be familiar with the type of questions and their level. Check the complete analysis of GATE CS paper from the table given below: 

Topics Question – 1 Mark Questions – 2 Mark
Engineering Mathematics 5 6
Theory of Computation 3 3
Compiler Design 1 2
Data Structures 4 4
Algorithms 2 2
Operating System 1 4
Computer Architecture and Organisation 1 2
Digital Logic 3 2
Database 3 1
Computer Networks 2 4

Check Detailed GATE Paper Analysis

GATE Computer Science Exam Pattern

GATE 2021 Computer Science and Information Technology Exam Pattern

  • The paper is held in online mode.
  • Candidates have to attempt 65 questions in the duration of  3 hours.
  • Questions are of 2 types- Multiple Choice types (MCQ) and Numerical Answer Type (NAT)
  • The total Marks for 65 questions is 100.
  • Candidate can use Virtual Calculator during exam as any other physical calculator is prohibited in GATE exam center. Check Complete GATE 2021 CS Exam Pattern
GATE CS Sectional Weightage
Engineering Mathematics 13%
General Aptitude 15%
Remaining Topics of CS 72%
  • There is no provision of negative marking in NAT questions.
  • MCQs carrying 1 marks each, 1/3 marks would be deducted as a penalty of marking the wrong answer.
  • For questions carrying 2 marks, 2/3 marks would be deducted for marking an incorrect answer.

Best Books for Computer Science

Books for GATE Computer Science and Information Technology

Books for computer science & Engineering
Books Authors/Publisher
GATE Computer Science & Information Technology GKP, G.K. Pub
TRB Lecturers ( Computer Science & Engineering ) Exam A panel of Authors, Sura College of Competition
A Handbook for Computer Science /IT Engineering Made Easy Editorial Board, Made Easy Publications
Graph Theory with Applications to Engineering and Computer Science Deo and Narsingh, Prentice Hall India Learning Private Limited
GATE 2020: Computer Science and IT Engineering Solved Papers ME Team, Made Easy Publications

How to Prepare for GATE Computer Science?

Preparation Tips for GATE CS Paper

Before moving on with some preparation tips, it is very important that candidates should have good knowledge about exam pattern and syllabus of Computer Science and Information Technology. For example, you can start with General Aptitude because this section does require much time and also the weightage of this section very less in the paper. Let's have a look at some beneficial preparation tips:

​1. Plan to Succeed

Your preparation should include all those things that will help you succeed. Include the best study material, books, online lectures, etc in your preparation plan. Candidates are advised to refer to their UG level books and notes to get in-depth knowledge of the subject. Candidates can also refer to the preparation tips of GATE toppers and if you found any useful point in their plan then do not hesitate to include that in your plan. Check  Preparation Tips from GATE Topper

​2. Hard Work and Smart Work

If candidates combine these two then nobody can stop you from cracking the exam. 

  • Hard Work: It includes daily practice, daily revisions, analysis of the level of preparation, etc. 
  • Smart Work: It includes week or day-wise division of syllabus, maintaining a strict time table, taking help from best books or video lectures, etc.

​3. Ask Questions

If you are attending any coaching classes then it is very easy for candidates to ask questions after every class. But for those candidates who are preparing at home by themselves, it is very difficult for them to get answers if they have any doubts. So these candidates can take the help of the internet to get their answers because it is good to have some questions after the completion of a topic as it will help you in getting better understanding of that topic.

​4. Division of Time as per Syllabus

Time Allotment Activities to Do
6:00 AM to 9:00 AM Pen down the important topics and scan all the important points/Prepare your Daily Study Plan
9:00 AM to 11:00 AM Take a Break
11:00 AM to 2:00 PM Pick up a Major Topic as you planned in the morning
2:00 PM to 6:00 PM Take a Break
6:00 PM to 9:00 PM Go through all the topics that you have covered in the day or you can also continue with the preparation of Major Topic
10:00 PM A quick go through of the Notes and try to sleep early

5. Practice Paper & Mock Tests

  • Previous year practice papers and mock tests are very important to include in the preparation plan. But you have to decide the right time to take these tests so that you can judge the level of your preparation, weaker areas, etc.
  • Some candidates prefer taking the mock tests after the completion of half syllabus while some candidates take a test when their whole syllabus is over.
  • However, you can simultaneously solve the questions of previous years' papers with the preparation of each major topic so that you can get an idea about the type of question asked from that particular section and weightage of marks form that section.

Download GATE Previous Years Papers

Preparation Tips from GATE Topper Ashwini Jain

Ashwini Jain had secured an All India Rank-11 in GATE 2017. Listen to the interview of Ashwini Jain and find out about her preparation strategies for GATE, the study material she referred, her study time table, and much more.

GATE Syllabus Of Other Papers

GATE Syllabus 2021 of Other Papers

It is very important to stay motivated during the time of preparation. This attitude plays a very important role in your success. Knowledge of all the vital details of GATE like syllabus, exam pattern, weightage of questions, etc will help in achieving your goal. 

Frequently Asked Questions

Frequently Asked Questions

Ques: Will there be any negative marking in GATE 2021?

Ans: Yes, there will be negative marking in the examination. Negative marking depends on the type and marks of questions. For NAT questions there will be no negative marking but for 1 or 2 marks ½ and 2/3 marks will be deducted respectively for wrong answers. 

Type of question Negative marking for wrong answer
MCQs 1/3 for 1 mark questions
2/3 for 2 marks questions
NATs No negative marking 

Ques: Based on the previous years papers can you suggest some important topics for GATE 2021 computer science?

Ans: Important topics are as follows:

  • Digital Logic
  • Computer Organization and Architecture
  • Programming and Data Structures
  • Algorithms
  • Theory of Computation
  • Compiler Design
  • Operating System
  • Databases
  • Computer Networks

Ques: I have study notes from my graduation. Will these notes be enough to prepare for the exam?

Ans: It is good that you have notes from your graduation because the syllabus of GATE 2021 computer science will be based on the topics from the graduation level. Other than these notes can also refer to the following books:

  • GATE Computer Science & Information Technology – By GKP, G.K. Pub
  • A Handbook for Computer Science /IT Engineering – Made Easy Editorial Board, Made Easy Publications

Ques: What will be the section-wise weightage of topics in GATE 2021 computer science?

Ans: The section-wise weightage in GATE 2021 computer science is as follows:

  • The maximum weightage will be given to the core subject i.e. 70%
  • 15% weightage will be given to general aptitude which is a common section for all 25 papers.
  • 15% weightage will be given to engineering mathematics. 
GATE CS Sectional Weightage
Engineering Mathematics 15%
General Aptitude 15%
Remaining Topics of CS 70%

*The article might have information for the previous academic years, which will be updated soon subject to the notification issued by the University/College.

GATE 2021 : 42 answered questions


Ques. What do you prefer, the GATE or the IES?

● Top Answer By Keshav Jindal on 25 Feb 21

Ans. I would prefer GATE or IES because in GATE the ratio is 10:1 whereas in IES the ratio is 300:1. This makes IES a very tough competitive exam but in GATE it is easier to get good marks and rank higher as the paper is easy and less competitive compared to IES.  The IES exam is tougher than GATE because here a candidate has to excel both in academics and personality. In GATE the questions are concept based and it is easier to solve if all the concepts are clear. Also in the GATE exam, there are 65 questions and the time limit is 3 hours but in the IES exam there are 120 questions and the time limit is 2 hours. So you get less time to solve all the questions.  After qualifying for your GATE exam with good marks, you can apply to any of the big companies with higher packages and it also opens your gate to apply for PSU.   After qualifying for your IES exam, you will get a job as an assistant executive engineer and after 3-4 years of experience, you will get promoted to executive engineer post. Then after many years of experience of like 20+ years, you will get Chief Engineer posts.Read more
1 Answer

Ques. What is the pattern for the written test for M.Tech at IIT Gandhinagar?

● Top Answer By Kumar Shiwam on 24 Feb 21

Ans. The admission for M. Tech at IIT Gandhinagar is done on the basis of academic records, written test, personal interview, and valid GATE scores. Those students who have a good academic record along with good GATE scores are not supposed to appear in the written test and personal interview.  The pattern of the written test is as follows: 10 questions of General aptitude questions consisting of logical analytical and reasoning ability and engineering mathematics are asked. 15-20 questions are asked related to basic courses in various disciplines up to the third year of an undergraduate program. The total duration of the written test is 1 hour for 80 marks. A total of 40 marks for general aptitude and 40 for basic knowledge. There is a negative marking and very basic questions are asked in the test. For branch subjects, all questions are asked related to SOM, fluid mechanics, etc.  The reservation category will get relaxation in the cut-off marks as per the norms. You will also be entitled to and fro sleeper class train tickets for the shortest route from your hometown to the institute. If you pass the test then you will attend the interview on the same day.Read more
1 Answer

Ques. What are the best coaching centres for GATE and IES in Civil Engineering?

● Top Answer By Sabeer Chalana on 23 Feb 21

Ans. There are many coaching centers throughout the country for IES and GATE coaching. However, these 2 institutes enjoy a huge reputation and recognition at the national level due to their experienced faculty and their study material quality. Made Easy: It is one of the best in the field when it comes to GATE and IES coaching. They have the best faculty teaching the subjects for the students.  Their specialty lies in their high quality and concise presentation. One of my friends enrolled in the Delhi center weekend coaching program, which he claimed to be good. Their online test series is one of the best you can opt for. They are prepared keeping the present pattern in mind. The number of students enrolled is hefty and gives you a clear picture of the competition. Some criticize that their teaching lacks depth compared to other institutes. Their courses and tests require analytical knowledge and are more than enough to crack GATE/IES exams. IES Masters: This institute is one of the best in this field and has earned respect for its excellence and quality coaching within a short span of its inception. All the major subjects for all batches are handled by Mr. Kanchan Thakur who is the director of the institute. He has a brilliant command over all the subjects in Civil engineering. The study material of this institute is best and is even recommended for those who choose civil engineering as an optional subject in UPSC exams. One small setback is that other faculties than the director are not on par when compared with the faculties of Made Easy. For the GATE Online test series, you can opt for Made easy test series, and for the IES test series you can opt for IES Masters. If you plan to join made easy to enroll in Super Talent Batch which has all top faculties teaching in this batch. For Classroom coaching for civil engineering in GATE/IES, Super talent batch can be preferred if not then IES Masters. For Postal study course, one can opt for IES masters.Read more
1 Answer

Ques. Which will be a better career for ECE engineers, IBPS SO or PSU via the GATE?

● Top Answer By Vaishnavi Agrawal on 19 Feb 21

Ans. Some of my friends work in both the departments and based on their experience, I can answer this. If you look at the position of an IBPS SO, it's that of a specialist officer. You'd technically be a network administrator of all of the intra networks of the bank. You'd be a database administrator/database manager who would have the entire intra network of that particular bank under your supervision.  Now if you look at the PSU job, you'd be someone who would be responsible for sustaining the technicalities concerning PSU. Your enquiry on which one is better entirely is up to you and where your interest lies. While some might opt for GATE which concerns their core subjects entirely, others simply might find their area of interest in networking. So, decide for yourself and choose what suits you and not the rest.Read more
1 Answer

Ques. What is the difference between IES and GATE?

● Top Answer By Himani Arora on 17 Feb 21

Ans. GATE and IES, are very well known among graduate engineers. The IES exam is carried out annually by the Union Public Service Commission (UPSC) and the GATE exam is administered by Bangalore's Indian Institute of Science (IISc) or any of the seven IITs. Syllabus and paper pattern: The complete engineering syllabus is covered by the IES exam, while GATE covers a portion of this syllabus and some other topics useful for higher studies.  While GATE tests problem-solving ability, IES tests conceptual capability.  The IES exam paper contains questions of the objective and subjective type and a total of 4 papers, while the GATE exam paper only contains questions of the objective type and only 1 paper.  Only in the subjective paper, a calculator is allowed. Difficulty Level & Duration: It will be much more difficult to solve the questions you will face in GATE than in IES.  In a single problem, GATE questions require you to apply many concepts. For that, you should have good problem-solving skills.  While most of the questions asked in IES are direct formula or a single concept based. In GATE, in 3 hours, you have to solve 65 questions that are approximately 2.5 minutes per question.  On the other hand, you have 120 questions in 2 hours to solve in IES. So, 1 minute per question which means you get nearly 2.5 times more “time” per question in GATE. But the difficulty level compensates for it. Category of PSUs and Job Scope: UPSC conducts IES examination to recruit candidates under the Govt for different engineering departments (mechanical, electrical, civil, and E&T).  Around India, The departments you get through IES are Indian Railway Service of Engineers, Indian Railway Stores Service, Indian Ordnance Factories Service AWM/JTS., Central Electrical and Mechanical Engineering Service, Geological Survey of India Engineering Service Gr ‘A’, Central Engineering Service (Roads), Gr ‘A’, Central Water Engineering Service Gr ‘A’, Indian Defence Service of Engineers, Central Power Engineering Service Gr ‘B’ and so on. The GATE exam is organized for higher studies (, PH. Ed. etc) and for placements in PSUs and Govt. Organizations. From the above-mentioned factual information, the difference between the two should be clear. Rest all depends on your choice what you opt for.Read more
1 Answer


vikram dewan
What is the exam pattern?
common admission test

Hii Vikarm, Greetings from collegedunia. GATE 2021 Exam Pattern has been revised and it is a 3-hour online test where candidates will have to attempt 65 questions carrying 100 marks. For more details visit GATE PATTERN

utkarsha khatri
What is the marking scheme?
common admission test

Hiii Utkarsha, GATE 2021 consists of 65 questions carrying 100 marks.  For MCQ type questions +1 or 2 marks will be awarded for correct answers whereas 1/3 marks will be deducted for 1 mark question and 2/3 for 2 mark questions. No negative marking is there in NAT and MSQs. For more details Click Here

How many questions are asked?
rakhisree chatterjee


Structure of the GMAT Exam

Test Section

Time Limit / Number of Questions

Question Types

Score Range

Analytical Writing Assessment

30 minutes
1 question

Analysis of an Argument

(in 0.5-point increments)

Integrated Reasoning

30 minutes
12 questions

Graphics Interpretation, Table Analysis, Multi-source Reasoning, Two-part Analysis

(in 1-point increments)

Quantitative Reasoning

62 minutes
31 questions

Data Sufficiency, Problem Solving

(in 1-point increments)

Verbal Reasoning

65 minutes
36 questions

Reading Comprehension, Critical Reasoning, Sentence Correction

(in 1-point increments)

For more information, please refer, GMAT Paper Pattern.

What is the cutoff of computer science engineering?
rakhisree chatterjee


Exam Paper Qualifying Marks
General OBC (NCL)
Computer Science and Information Technology (CS) 29.5 26.6

For more information, please refer, GATE Exam Cut Off.

Can I get some ideas of the type of questions they asked? ?
abdul nazir

Hi Pradeepraj, To get an exact idea of GATE exam pattern and type of questions that can be asked, you need to attempt more and more practise papers and mock test series. You can download GATE previous year question papers for differents subjects in pdf format by visiting the link here.

sourajit mukherjee
Can I get links of some really good books ?
common admission test

Hii Sourajit, Greetings from collegedunia. The right preparation book at the right time of preparation can be helpful to crack the exam. To know Which are the best books for GATE 2021, Click Here

I have done my BA in Economics with subsidiary Pol Sci. Am I eligible to appear for the GATE exam as per new syllabus and new rule made by govt?
rakhisree chatterjee

Hi, Eligibility. The following students are eligible to take GATE: Bachelor's degree holders in Engineering / Technology / Architecture (3 years after 10+2/ 10+2+3(ongoing)/ 10+2+4(ongoing)/ Post-B.Sc./ Post-Diploma) and those who are in the final year of such programs.

Can I get ebooks of every subject with the question came from that book?

Hi Devisingh

Yes you can get the online books for preparation of GATE exam. Those books also includes questions for preparation. You can visit on Gate Recommended Books to check out some good books for your preparation.

From which book should I prepare?
rakhisree chatterjee

Hi, Candidates should refer to the books that have been preferred by the B.Tech students for four years. Each book has its own methodology, so in-depth study of the GATE Preparation books can help you score well.

rinki mahapatra
Does it include the complete syllabus of BE?

Dear Rinki Mahapatra

Greetings from Collegedunia. Yes, the complete syllabus of B.E. is admitted to GATE Examination 2021 as it contributes 72% marks out of total marks. For more details, kindly go through this link – GATE 2021 Syllabus

How can i complete my gate preparation in 4 months that its very late that i started now could you please help out in this

Hello Manaswiketha, greetings from Collegedunia. Click here for valuable preparation tips about how to efficiently prepare for the GATE exam 2020.