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Open Source · Free Forever · Interactive

Learn Python the way
it actually works

Not just syntax — memory, reasoning, and mental models. Every concept visualized. Every question answered. Python from first principles.

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🧠 Memory model visualized
▶ Step-by-step animation
📱 Works on any device
⚡ No install needed
🔓 Open source

Course Sessions

Each session builds on the last. Animations, quizzes, memory diagrams — all included.

01
Variables & Mutability
What is a variable really? What happens in memory when you write x = 5? Why can you change a list but not a string? Understand Python's object model from the ground up.
int str list id() memory model reference counting
02
Functions & the Call Stack soon
How functions create frames, pass arguments, and return values. Stack diagrams animated.
def call stack scope LEGB
03
Lists, Dicts & References soon
Shallow vs deep. Aliasing. Why modifying a list inside a function changes it outside. Visualized.
list dict shallow copy aliasing
04
Classes & Objects soon
What is self? How does Python find attributes? The MRO, __init__, and instance vs class vars.
class self __init__ MRO
05
Iterators & Generators soon
How for loops really work. The iterator protocol. Lazy evaluation and yield.
iterator generator yield lazy evaluation

Why another Python course?

01
Most courses teach syntax. This one teaches understanding.
You can memorize list.append() in five minutes. But do you know why lists are mutable and strings aren't? What actually happens in RAM when you write x = x + 1? That's what we care about.
02
Animations over slides.
Every concept is animated. You watch the variable bind to an object. You see the reference count tick up. You watch the garbage collector sweep. You can pause, rewind, and go at your own speed.
03
Open source. Always free. No account needed.
Hosted on GitHub Pages. Fork it, extend it, translate it. The license lets you use the visuals and content freely — just give credit.
04
Mobile-first, no install.
Pure HTML, CSS, and JavaScript. No build tools, no Node, no backend. Works offline after first load. Open on your phone on the bus. Close. Come back. It remembers where you were.