Divided into two parts, the book discusses what analog computing is and why it has the potential to be the key enabling technology for the next generation of AI hardware. The first part discusses the fundamental concepts necessary to understand analog neuromorphic processors, from an introduction to modern AI and its models, to the discussion of its shortcomings and ending with an in-depth discussion on analog signals. The second part presents electronic and photonic analog architectures encompassing memristor arrays, spiking neurons, and reservoir computing. This book aims to introduce AI and analog devices at various levels of analysis to anyone interested in the field, from science enthusiasts to graduate students and professionals. Its structured and pedagogical approach also makes it a prime candidate for textbook adoption in suitable university-level courses.