DataslopeWelcome
A comprehensive, hands-on Python basics course that runs in your browser
Welcome to Python Basics, a hands-on course that takes you from your
very first print("hello") all the way to writing classes, generators,
and decorators. By the end you will be comfortable enough with the
language to dive into advanced topics like async programming, the
typing system, web frameworks, or scientific computing.
What you will learn
The course is organized into short, focused pages. Each page mixes explanation with three kinds of interactive widgets:
- Executable code blocks. Every snippet runs in your browser — no setup required. Edit any block and click Run to see the result.
- Challenge cards. Small coding problems with hidden test cases. Some are single-file; a few use multiple files so you can practice importing across modules.
- Multiple choice questions. Quick checks at the end of most pages. They give you per-choice feedback so a wrong answer is still a learning opportunity.
How to use the interactive widgets
Each code block runs in a fresh Python scope, so a variable defined in one block is not visible in the next unless the block has its own initialization code. This keeps examples isolated and easy to reason about. If you want a persistent, longer-lived workspace, open the Python Playground in a new tab.
Course outline
The pages are designed to be read in order, but each one stands on its own if you want to jump around.
1. Foundations
History, installation, your first program, and indentation rules. You will learn why Python chose significant whitespace and why the tabs-vs-spaces debate still sparks arguments at conferences.
2. Values and types
Variables, numbers, strings, booleans, and how Python's dynamic typing
works. We will explore what happens under the hood when you write x = 42
and why a = []; b = a creates shared state.
3. Collections
Lists, tuples, dictionaries, and sets, plus when to reach for each one.
You will learn the difference between mutable and immutable, what a hash
table is, and why key in my_dict is so fast.
4. Control flow
Conditionals, loops, and the comprehension shortcuts that make Python so concise. By the end of this section you will be writing nested list comprehensions and understanding when to unpack them back into loops.
5. Functions and modules
Defining your own functions, organizing code into modules, and handling
errors gracefully. We will cover scope, closures, *args and **kwargs,
and the import system.
6. Object-oriented Python
Classes, inheritance, dunder methods, and a first taste of iterators, generators, and decorators. This is where Python's flexibility really shines — and where beginners often get lost, so we take it slow.
7. Going further
Virtual environments, pip, and a roadmap of intermediate and advanced topics worth exploring next: async/await, type hints, context managers, metaclasses, and the rich ecosystem of data science, web, and DevOps libraries.