Fundamentals

Build your AI mental model from zero — structured from easy to hard

00 Lv.1 Beginner

Reading Guide: Beginner Path vs Professional Path

First time here? This article tells you what to read, how to read it, and what you can skip—pick a path based on your background.

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01 Lv.1 Beginner

What Is AI? Three Metaphors That Make It Click

No formulas, no jargon pile-up—three everyday metaphors to build a first-principles understanding of artificial intelligence.

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02 Lv.2 Beginner

How LLMs "Talk": Tokens, Context, and Probability

Three core mechanisms—tokenization, context windows, and probabilistic sampling. Understand these and AI stops feeling like magic.

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03 Lv.2

Prompt Basics: How to Ask AI and Get Good Answers

Five practical techniques—from casual questions to reliable output. No spellbooks—just clarity about what you want.

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04 Lv.3

What Is RAG? Let AI Read Your Docs Before Answering

Retrieval-Augmented Generation end to end: chunking, embedding, retrieval, generation—one diagram and clear steps.

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05 Lv.3

AI Agents: From Chat to Getting Work Done

Agents plan steps, call tools, and execute autonomously. Understand the loop and you'll see what Cursor and Devin are doing.

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06 Lv.4 Pro

Fine-Tuning vs RAG vs Long Context: How to Choose

Three ways to make AI more domain-aware—when each fits, what it costs, and where it breaks. One decision table.

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07 Lv.4

Multimodal AI: Eyes and Ears for Models

Text, images, audio, video—how multimodal AI unifies them, what works today, and what still doesn't.

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08 Lv.5 Pro

AI Production Checklist: From Demo to Product

Ten checks for shipping AI in real products—security, cost, eval, monitoring. None optional.

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