This book is about the Arduino microcontroller and the Arduino concept. The visionary Arduino represented a new innovation in microcontroller hardware in 2005, the concept of open source hardware, making a broad range of computing accessible for all. This book, “Arduino V: AI and Machine Learning,” second edition, is an accessible primer on Artificial Intelligence and Machine Learning for those without a deep AI and ML background. The author concentrates on Artificial Intelligence (AI) and Machine Learning (ML) applications for microcontroller–based systems. The intent is to introduce the concepts and allow readers to practice on low cost, accessible Arduino hardware and software. Readers should find this book a starting point, an introduction, to this fascinating field. A number of references are provided for further exploration.