Python from zero to advanced

A free Python course for Class 11-12 (CBSE Computer Science and Informatics Practices) and first-year college students (B.Tech, BSc, BCA), from your first print() to decorators, generators, pandas and the questions Python interviews ask. Every lesson has runnable examples and auto-checked practice that runs real Python in the browser, on a phone too.

Part 1 · Foundations

From your first print() to files: everything every board and university syllabus shares.

Module 1: Start coding

Write and run your first programs: print, numbers, names, text and input. A working bill calculator by lesson 4.

Module 2: Decisions and loops

Make programs choose (if/elif/else) and repeat (while, for, range), from grade calculators to star patterns and number programs.

Module 3: Functions

Package code into reusable functions with parameters and return values, understand scope, and use modules like math and random.

Module 4: Strings

Index, slice and transform text: string methods and the classic string programs every exam asks.

Module 5: Lists and tuples

Store many values: lists, the aliasing trap, list patterns, nested lists, stacks, comprehensions and tuples.

Module 6: Dictionaries and sets

Look things up by key: dictionaries, records, counting and sets, and how to pick the right collection.

Module 7: Errors and debugging

Read tracebacks, handle errors with try/except, raise your own, and debug like a pro.

Module 8: Files

Read and write text, CSV and JSON files so your programs remember things.

Part 2 · Core Python

Object-oriented programming and data with NumPy and pandas.

Module 9: Object-oriented programming

Model the real world with classes: objects, encapsulation, inheritance, polymorphism and good object design.

Module 10: NumPy and pandas

Work with data: NumPy arrays, pandas Series and DataFrames, grouping and charts.

Part 3 · Advanced Python

Decorators, generators, internals, testing, real-world Python and concurrency: what interviews ask.

Module 11: Functions in depth

*args and **kwargs, functions as objects, closures and decorators: the tools behind clean Python.

Module 12: Iteration and the standard toolkit

Comprehensions, iterators and generators, and the built-ins and modules (collections, heapq, itertools) that save you code.

Module 13: Python under the hood

Objects and identity, copies, memory management, how list and dict really work, and the GIL.

Module 14: Exceptions, context managers and testing

Custom exceptions, writing your own with-blocks, logging and testing with pytest.

Module 15: Real-world Python

Packages and virtual environments, talking to web APIs, and databases with sqlite3.

Module 16: Concurrency

Threads, processes and asyncio: doing many things at once, and when each one helps.

Exam packs

Extra lessons for the CBSE Class 12 board and for first-year university exams.

Pack A: CBSE Class 12 Board Pack

Everything extra the CBSE Computer Science (083) board asks: binary files, CSV, stack, SQL and Python-MySQL, plus board-style drills.

Pack B: College Semester Pack

The extra topics first-year university syllabi add: recursion, searching and sorting, file automation, regex and a mini game.

Practice and reference