FRONT COVER MATTER

ABOUT THIS BOOK Welcome! This book teaches you how to become a Certified Artificial Intelligence (AI) Harness Engineer. AI is the field of building computer systems that do things we normally associate with human thinking, such as understanding language, spotting patterns, and making decisions. A harness engineer is a person who designs, builds, tests, and looks after the surrounding software that lets an AI system do real work safely. You do not need any background to begin. If you have never written a line of code, you can still follow every chapter, because each new idea is explained with everyday comparisons and step-by-step examples. If you already know some programming, you will find the explanations helpful as a way to fill gaps, and you can move faster through the early material. Here is how the book is built. First, the book is divided into Parts. A Part is a large section that covers one big theme, such as foundations or safety. Second, each Part is divided into Chapters. A Chapter covers one topic in depth, and every chapter follows the same pattern so you always know what to expect. Third, every chapter contains the same seven Sections. Section one is the teaching text itself, which walks through every topic and subtopic in plain language. Section two is a section called Examples, in which concrete situations are walked through from beginning to end so you can see the ideas in action. Section three is called Practice Lab Connection, which tells you how to try the chapter's ideas on a hands-on project that you will build as you read. Section four is called Artificial Intelligence Assistant Prompts, which gives you ready-to-use instructions you can paste into an AI assistant so that it helps you do on-the-job tasks that a working harness engineer really does. Section five is the Chapter Summary, a short recap. Section six is the Key Terms Review, a list of the vocabulary you should now own. Section seven is Check Your Understanding, a handful of questions with brief answers so you can test yourself. A word about jargon. Jargon means specialized words that insiders use and outsiders find confusing. Every time this book uses a jargon term for the first time, it stops and explains the term in plain language right on the spot. Every acronym, which is a short form made from the first letters of a longer name, is spelled out the first time it appears, followed by the short form in parentheses. For example, you will see Large Language Model (LLM) the first time and later simply LLM. A word about facts and dates. This field moves quickly, and tools, product names, and statistics change from month to month. This book was checked against sources current to late 2026 where possible. Where a number or claim is approximate or reported by industry observers rather than proven, the text says so plainly. Where the author is not sure of something, the text says that too, rather than guessing. Please treat any product name or statistic as a snapshot in time, and check the official documentation of any tool before you depend on it. A word about the AI assistant prompts. Each prompt contains placeholders written in square brackets, such as [PASTE YOUR TEXT HERE]. Before using a prompt, replace each bracketed placeholder with your own real material. Never paste secrets such as passwords or access keys into any prompt. Always read what the assistant returns with a critical eye, because assistants can make mistakes, a problem you will study closely in Chapter 2.