This book provides a rigorous yet accessible foundation in reinforcement learning (RL), focusing on the mathematical principles and practical methods that underpin modern AI. It explains how RL differs from supervised and unsupervised learning, and why its feedback driven structure makes it uniquely suited to interactive environments. Reinforcement Learning Explained introduces the agent–environment interaction loop, the formalism of Markov Decision Processes (MDPs), value functions, and Bellman equations. It then develops classical solution methods, including dynamic programming, Monte Carlo techniques, and temporal-difference learning, leading to SARSA and Qlearning. Each concept is reinforced through intuitive explanations, step-by-step derivations, numerical examples, diagrams, and Python implementations. Readers will not only learn the theory but also practice it. Each chapter is supported with exercises, complete solutions, and a companion Python codebase that allows for hands-on experimentation. This book is designed as a self-contained textbook and reference. It may serve as the foundation for graduate-level RL courses, as a supplement in AI and machine learning curricula, or as a structured guide for self-study. Beyond academia, the book will appeal to industry professionals in fields such as robotics, autonomous systems, finance, and healthcare, where reinforcement learning is increasingly applied.
