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Thirteen explainers, in the order that makes them easiest to absorb. Each one stands alone, but read in sequence they build on each other — later pieces assume the vocabulary earlier ones establish.

If you only have twenty minutes, read the first two. If a term stops you, the glossary defines it in a line and links back to the explainer that covers it properly.

Foundations

What these systems are and how they represent language. Everything else assumes this.

1

What Is a Large Language Model?

The single mechanism — next-token prediction — that explains both what these systems can do and how they characteristically fail.

2

Tokens and Embeddings

Why a model cannot count letters, why some languages cost three times more, and how meaning becomes geometry.

3

Transformers Explained

The architecture underneath everything since 2017, and why attention made scaling possible.

4

Context Windows Explained

The hard limit every AI application is designed around, and why a bigger window is not automatically better.

What they can do

The four patterns that account for most of what gets built on top of these models.

5

RAG Explained

How systems answer questions about private or current data the model was never trained on.

6

Fine-Tuning vs RAG vs Prompting

The decision that costs teams the most money when they get it wrong. One question sorts it.

7

Tool Use and MCP

How a model stops merely talking and starts doing — and where the security boundary actually sits.

8

AI Agents Explained

What agents genuinely do well, where they fail, and why the honest picture is narrower than the marketing.

9

Reasoning Models Explained

Spending more computation at the moment a question is asked, and when that helps rather than hurts.

Where they break

Read these before trusting any of the above in something that matters.

10

Why AI Models Hallucinate

Not a bug awaiting a patch — a predictable result of how models are trained and, crucially, how they are graded.

11

AI Benchmarks Explained

Why most widely-quoted scores are saturated, contaminated, or not comparable between models.

The physical layer

AI capability is downstream of hardware and, increasingly, electricity.

12

The AI Compute Stack

Why memory and packaging rather than arithmetic are the scarce resources, and why power became the binding constraint.

13

How Self-Driving Actually Works

The most visible real-world test of AI, and the vocabulary that separates capability from marketing.


Canon pieces are maintained rather than published and forgotten — each carries the date it was last reviewed. If something reads as out of date, it probably is, and corrections are welcome.