Get the complete CBSE Class 12 Computer Science Syllabus 2026-27 with unit-wise topics, marks distribution, exam pattern, and expert tips. Everything you need in one place.

Quick Overview

Exam Structure 2026-27

The CBSE Class 12 Computer Science theory paper has 70 marks and the practical carries 30 marks.

Theory Paper Pattern (70 Marks)

Unit-Wise Marks Distribution 2026-27

Focus most on Unit 1 and Unit 2 as they carry the highest combined weightage.

Complete Syllabus 2026-27: All Units, Chapters and Topics

Use the checklist below to track your chapter-wise preparation.

Unit 1: Computational Thinking and Programming - 2 (30 Marks)

Chapter 1: Exception Handling in Python

•        What is an exception vs syntax error

•        try, except, else, finally blocks

•        Raising exceptions using raise

•        Common built-in exceptions: ZeroDivisionError, ValueError, TypeError, FileNotFoundError

Chapter 2: File Handling in Python

•        Text files vs Binary files vs CSV files

•        Opening, reading, writing and closing files: open(), read(), readline(), readlines(), write(), close()

•        File access modes: r, w, a, r+, rb, wb

•        CSV file handling using csv module: reader() and writer()

•        seek() and tell() functions

Chapter 3: Stack

•        Stack: definition, LIFO principle

•        Operations: PUSH, POP, PEEK, isEmpty, isFull

•        Implementation using Python list

•        Applications of stack

Chapter 4: Queue

•        Queue: definition, FIFO principle

•        Operations: ENQUEUE, DEQUEUE, isEmpty, isFull

•        Implementation using Python list

•        Circular Queue - concept only

Chapter 5: Searching and Sorting Algorithms

•        Linear Search - algorithm, Python code, time complexity

•        Binary Search - algorithm, Python code, time complexity, prerequisite (sorted list)

•        Bubble Sort - algorithm, Python code, time complexity

•        Insertion Sort - algorithm, Python code, time complexity

•        Selection Sort - algorithm, Python code, time complexity

Unit 2: Computer Networks (15 Marks)

Chapter 6: Networking Basics

•        Types of networks: PAN, LAN, MAN, WAN

•        Network topologies: Bus, Star, Ring, Tree, Mesh

•        Transmission media: twisted pair, coaxial, optical fibre, wireless

•        Network devices: Hub, Switch, Router, Modem, Gateway, Repeater, Bridge

Chapter 7: Network Protocols and Addressing

•        TCP/IP model - 4 layers and their functions

•        OSI model - 7 layers (reference only)

•        IP addressing: IPv4 vs IPv6, classes of IP

•        MAC address - definition and purpose

•        Key protocols: HTTP, HTTPS, FTP, SMTP, POP3, DNS, DHCP

Chapter 8: Internet and Web Services

•        World Wide Web, URL, domain names, web browsers

•        Web server vs Web client

•        Cloud computing basics: SaaS, PaaS, IaaS

•        Wireless technologies: Wi-Fi, Bluetooth, 3G/4G/5G, WiMAX

•        Network security threats: Malware, Phishing, Denial of Service (DoS)

Unit 3: Database Management (15 Marks)

Chapter 9: Database Concepts

•        DBMS vs File System

•        Key terms: Database, Table, Record, Field, Primary Key, Foreign Key, Candidate Key

•        Advantages of DBMS

•        Relational data model - tables, tuples, attributes

Chapter 10: Structured Query Language (SQL)

•        DDL commands: CREATE, ALTER, DROP, TRUNCATE

•        DML commands: INSERT, UPDATE, DELETE, SELECT

•        SELECT with: WHERE, ORDER BY, GROUP BY, HAVING, DISTINCT, LIKE, BETWEEN, IN

•        Aggregate functions: COUNT(), SUM(), AVG(), MIN(), MAX()

•        Joins: INNER JOIN, LEFT JOIN, RIGHT JOIN, CROSS JOIN

•        NULL handling: IS NULL, IS NOT NULL

Chapter 11: Python-MySQL Connectivity

•        mysql.connector module

•        Connecting Python to MySQL: connect(), cursor()

•        Executing queries: execute(), fetchone(), fetchall(), fetchmany()

•        Committing and rolling back transactions

Unit 4: Society, Law and Ethics / Cyber Safety (10 Marks)

•        Cyber crime: hacking, identity theft, cyber bullying, phishing

•        Intellectual Property Rights (IPR): copyright, patent, trademark

•        Open source software vs proprietary software

•        Digital footprint - active vs passive

•        IT Act 2000 - key provisions

•        E-waste management - responsible disposal

•        Ethical issues: plagiarism, digital rights, data privacy

•        Net neutrality - concept and importance

Practical Syllabus 2026-27 (30 Marks)

Tip: Your practical file must include programs covering file handling, stacks, queues, sorting, SQL, and Python-MySQL connectivity.

Important Dates 2026-27

Always verify dates on cbse.gov.in.

Chapter-Wise Priority at a Glance

Study Tips for CBSE Class 12 Computer Science

1. Code Every Day

•        Do not just read programs - run every program in Python yourself

•        Modify existing programs to test your understanding

•        Maintain a separate coding notebook for all data structure programs

2. Master SQL by Practising Queries

•        SQL is the easiest 10-12 marks in the paper if practised daily

•        Practice SELECT with WHERE, GROUP BY, HAVING, ORDER BY and JOINs

•        Install MySQL locally and run queries - hands-on practice beats theory

3. Focus on File Handling Thoroughly

•        File handling questions appear every year for 8-10 marks

•        Practice all modes: r, w, a, rb, wb and CSV file read/write

•        Understand seek() and tell() - they are frequently asked

4. Learn Algorithms with Dry Runs

•        For sorting and searching, always practice dry run (trace table) on sample data

•        Write the algorithm, code, and time complexity for each

•        Compare algorithms: Binary Search vs Linear Search, Bubble vs Insertion vs Selection Sort

5. Revise Networking and Ethics Smartly

•        Do not skip networking - 15 marks are at stake

•        Make a one-page cheat sheet of all protocols, ports, and devices

•        Ethics and cyber law topics are direct memory-based marks - read once, revise twice

Scoring Tips for the Board Exam

•        Write programs with proper indentation - Python is indentation-sensitive and marks are deducted for errors

•        For SQL, always use correct syntax with proper capitalisation of keywords

•        In file handling questions, mention the file mode used - it carries marks

•        For stack/queue, draw a step-by-step trace of PUSH/POP/ENQUEUE/DEQUEUE operations

•        Show variable tracing in sorting programs - partial marks are given for correct logic

•        Attempt all MCQs - no negative marking in CBSE

•        For 4-5 mark questions, write answers in structured points with proper headings

•        Start with the section you are most confident about to secure marks early

Common Mistakes to Avoid

•        Incorrect indentation in Python - the single biggest reason for lost marks in programming questions

•        Confusing stack (LIFO) with queue (FIFO) operations

•        Using wrong file mode - e.g., opening a file in 'w' mode when 'a' is needed

•        Forgetting to commit() after INSERT/UPDATE/DELETE in Python-MySQL programs

•        Writing SQL keywords in lowercase without consistency - be consistent with UPPERCASE for SQL keywords

•        Confusing fetchone() with fetchall() in connectivity programs

•        Not practising networking - students skip this and lose 15 easy marks

•        Leaving CSV file handling unpractised - it appears every year

Best Resources for Preparation

•        NCERT Computer Science Class 12 Textbook - start here, CBSE follows it strictly

•        CBSE Sample Papers 2026-27 on cbseacademic.nic.in - must solve before the exam

•        Sumita Arora - Computer Science with Python - most popular reference book

•        Preeti Arora - Computer Science Class 12 - good for SQL and networking sections

•        CBSE Question Bank - for chapter-wise objective practice

Frequently Asked Questions

Q1. Is Python the only programming language in CBSE Class 12 CS?

Yes. Python is the only programming language in the CBSE Class 12 Computer Science syllabus for 2026-27.

Q2. Which unit carries the most marks?

Unit 1 - Computational Thinking and Programming - 2 carries 30 marks, making it the highest-weightage unit. File handling, stacks, queues and sorting are the key topics.

Q3. Is SQL included in the Class 12 CS syllabus?

Yes. SQL is a core part of Unit 3 and covers DDL, DML commands, aggregate functions, and joins. Python-MySQL connectivity is also included.

Q4. How many programs must the practical file contain?

The practical file must have a minimum of 15 programs covering file handling, data structures, SQL, and Python-MySQL connectivity.

Q5. Is NCERT enough for scoring 90+ in CS?

NCERT plus Sumita Arora is the standard combination for 90+. Solve all NCERT exercises and practice SQL queries and Python programs daily.

Disclaimer

This content is based on the official CBSE Computer Science curriculum. Always verify the latest syllabus on cbse.gov.in and cbseacademic.nic.in as CBSE may update it.