Class 11 Computer Science Notes : CS Notes Class 11 Topic Wise

Class 11 Computer Science Notes

Class 11 Computer Science Notes are designed to make computer science and programming concepts accessible and understandable for CBSE students.  These Computer science Notes designed specifically for CBSE students of Class 11. Developed with the latest CBSE Computer Science Syllabus 2023-24 in mind, these notes aim to simplify complex concepts, making them easily understandable and accessible.

These Class 11 Computer Science Notes will guide you through essential topics such as Python programming, data types, control structures, data structures, functions, file handling, and more. You will also explore broader areas of computer science, including societal, legal, and ethical considerations related to technology.

Class 11 Computer Science Notes

Unit: 1 Computer Systems and Organisation

Unit II: Computational Thinking and Programming – I

Unit III: Society, Law and Ethics


Python – Getting started: The notes begin by introducing Python, a programming language that is easy to learn and widely used. Students will learn the basics of setting up Python and get started with writing their first programs.

Python Variable: Variables are like containers that store data in a program. These notes explain how to declare and use variables in Python, allowing students to store and manipulate different types of information.


Python Keyword & Identifiers: Python has reserved words called keywords that have specific meanings in the language. Identifiers are names used for variables, functions, and other programming elements. This topic explains the rules for choosing identifiers and the importance of using appropriate names.


Python Operators: Operators are symbols or special words used to perform calculations or operations in Python. The notes cover different types of operators, such as arithmetic, comparison, and logical operators, and how they can be used to perform specific tasks.


Python Number Data Type: Numbers are a fundamental data type in programming. Students will learn about different types of numbers in Python, such as integers and floating-point numbers, and how to perform mathematical operations with them.

Class 11 Computer Science Notes

Python String Data Type: Strings represent text in Python. The notes explain how to work with strings, including operations like concatenation and slicing, as well as functions that can manipulate and analyze text.


The Python while loop is a fundamental control structure that allows students to repeat a set of instructions as long as a specific condition is true. The while loop notes explain the syntax and usage of this loop, highlighting its ability to handle situations where the number of iterations is not known beforehand. Students learn how to construct a while loop, set the initial condition, and update the condition within the loop to control its execution. 

The Python for loop is a powerful construct used for iterating over a sequence of elements. It allows students to perform a set of actions repeatedly for each item in a collection, such as a list or string. The notes explain the syntax and usage of the for loop, emphasizing its versatility and efficiency in handling repetitive tasks. 


Python if…else statements: Conditional statements allow programmers to make decisions in their programs based on certain conditions. The notes explain the “if…else” statement, which enables students to execute different blocks of code based on specific conditions.


Python Jump Statement: Jump statements alter the normal flow of a program. This topic covers “break” and “continue” statements, which allow students to exit a loop prematurely or skip certain iterations.

Python lists are versatile and widely used data structures that allow students to store and manipulate collections of elements. The list notes provide a comprehensive understanding of lists, covering their creation, indexing, and manipulation. Students learn how to add and remove elements from a list, access specific elements using indexing and slicing, and perform common operations like sorting and reversing. 

Python tuples are similar to lists, but with one key difference: they are immutable, meaning they cannot be modified once created. The tuple notes provide a concise understanding of tuples, covering their creation, accessing elements, and various operations that can be performed on them. 

Python dictionaries are powerful data structures that allow students to store and retrieve data using key-value pairs. The dictionary notes provide a comprehensive understanding of dictionaries, covering their creation, accessing values, and performing operations on them. Students learn how to create dictionaries using curly braces or the dict() function, access values by providing the corresponding key, and modify or add new key-value pairs. 

Python Function: Functions are blocks of reusable code that perform specific tasks. Students will learn how to define and use functions, making their programs more organized and efficient.


Python File Handling: File handling involves reading from and writing to files on a computer. The notes explain how to open, read, write, and close files using Python, allowing students to work with external data.


Python Datetime: Dates and times are essential in many programs. The notes introduce the datetime module, which provides functions to work with dates, times, and time intervals in Python.

Python Tkinter: Tkinter is a library for creating graphical user interfaces (GUIs) in Python. Students will learn how to build interactive desktop applications using Tkinter’s various components.


Society, Law & Ethics: This section explores the broader impact of technology on society, the legal aspects related to computers and data, and ethical considerations such as privacy, security, and responsible use of technology.

Happy learning and success in your computer science journey!

Class 11 Computer Science Notes