An interactive tutorial
How language models
actually work, from the ground up.
A first-principles path through tokens, embeddings, attention, and the machinery behind LLMs, built up step by step, with worked examples and runnable code that make it stick.
15 lessons across 2 chapters · ~83 min · free to read
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Highlight & note
Mark up the text. Your highlights and notes sync across devices.
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Spaced review
Key ideas resurface on an FSRS schedule so they stay learned.
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Exercises
Predict tokenizer output, trace algorithms, and check your understanding with instant feedback.
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- Every chapter, start to finish
- Nothing stored on a server
- Zero tracking
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- Progress tracking
- Highlights & notes
- Dark & sepia themes
- Full-screen focus mode
- Spaced review — synced across devices
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