[CodeTrain](https://codetrain.ai/) / Learn

# Every course, class by class

These are the **curated** courses, written by hand as a place to start. A course is a line, each class is a stop along it, and every class is a set of hands-on lessons where you type each small step yourself. You are not limited to them: ask CodeTrain for **any topic** and it builds the lesson on the spot, or point it at **any public repository** and it teaches you that codebase instead.

[Start free, no card](https://codetrain.ai/app/)

## Curated courses

### [Learn to Code in Python](https://codetrain.ai/learn/python-intro/)

Start from zero and write real Python from your very first line.

[Foundations](https://codetrain.ai/learn/python-intro/py-foundations/)[Collections](https://codetrain.ai/learn/python-intro/py-collections/)Writing robust code (soon)

### [Object-Oriented Python](https://codetrain.ai/learn/python-oop/)

Model real things with classes, and learn when OOP earns its keep.

[Classes & objects](https://codetrain.ai/learn/python-oop/oop-classes/)Inheritance & polymorphism (soon)

### [JavaScript Fundamentals](https://codetrain.ai/learn/js-intro/)

The language that runs the web: values, arrays, and control flow.

[Values & arrays](https://codetrain.ai/learn/js-intro/js-values/)Control flow (soon)

### [JavaScript: Functions & Data](https://codetrain.ai/learn/js-functions/)

Functions are values: pass them around, return them, and capture state.

[Functions & closures](https://codetrain.ai/learn/js-functions/jsf-functions/)Async JavaScript (soon)

### [Command the Terminal: Linux & Bash](https://codetrain.ai/learn/bash-intro/)

Stop fearing the shell. Move around, wire commands, automate the boring parts.

[First commands](https://codetrain.ai/learn/bash-intro/sh-first/)[Text & pipes](https://codetrain.ai/learn/bash-intro/sh-text/)

### [How LLMs Actually Work](https://codetrain.ai/learn/llm-foundations/)

From a single neuron to a working transformer, built from scratch in pure NumPy, in your browser.

[Neural-net foundations](https://codetrain.ai/learn/llm-foundations/llm-foundations-1/)[Tokens & embeddings](https://codetrain.ai/learn/llm-foundations/llm-foundations-2/)[The Transformer block](https://codetrain.ai/learn/llm-foundations/llm-foundations-3/)[Training, generation & fine-tuning](https://codetrain.ai/learn/llm-foundations/llm-foundations-4/)

### The Backend Course · coming soon

### The Web Course · coming soon

### Data with Python · coming soon

## How CodeTrain teaches this

No videos and no multiple-choice quiz at the end. Each lesson is a handful of small steps in a real editor. You type the code yourself, it runs, and the tutor reviews what you actually wrote. It will not hand you the answer, and the step doesn't advance until your code passes. What you get at the end is a record of which steps you wrote unaided, not a completion percentage.

## These curated courses are the starting point, not the product

Everything in this catalog is a **curated** course we wrote by hand. They exist so there is something to start on. What CodeTrain actually does is build a lesson on demand: name **any topic** you want to understand and it writes one for you on the spot, or paste **any public repository** and it teaches you that codebase from the code that is really in it. You are not limited to the list below, and most people stop using it within a session or two.

## Guides

If you would rather understand the method, bring your own code, or read about learning itself than pick a course off the list.

### [How a Socratic coding tutor works](https://codetrain.ai/learn/socratic-method/)

The rules the tutor runs under, quoted from the prompt, and what they do to a real step.

### [Learn any codebase in 30 minutes](https://codetrain.ai/learn/understand-a-codebase/)

Paste a public repo and learn it by writing in it. The path, step by step, and what it refuses to read.

### [Why AI coding assistants stop you learning](https://codetrain.ai/learn/why-ai-assistants-stop-you-learning/)

Reading a correct answer feels like understanding it. The two come apart weeks later, when the code breaks and none of it is truly yours.

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Source: https://codetrain.ai/learn/

This is the markdown twin of the page above. Every public CodeTrain page serves one on `Accept: text/markdown`. Start at https://codetrain.ai/llms.txt for the full map, or https://codetrain.ai/developers/ for the API.