Thinking in Tokens

A Mental Model for Modern AI Systems

Welcome

A conceptual introduction to how modern AI actually works — tokens, embeddings, attention, transformers, training, hallucination, retrieval, tool use, agents, reasoning models — written for curious, intelligent readers with no math, no programming, and no prior ML background.

Most explanations of AI are either marketing (“it’s magic”) or academic (equations first, intuition never). This book builds one cumulative mental model, incrementally, rather than presenting AI as a list of disconnected techniques and product names — one that keeps working as the technology changes.

This is a first complete draft, not a finished, professionally edited book.