In recent years, natural language processing has significantly advanced in developing large language models that can generate human-like text. Among these models, ChatGPT (Generative Pre-trained Transformer) stands out as one of the most influential and versatile models, capable of generating coherent and relevant responses to a wide range of inputs. In this book, ""Understanding ChatGPT,"" I aim to introduce the capabilities of ChatGPT and potential applications. Additionally, we will explore some of the challenges and limitations of the model. I shall also discuss working on this platform, the benefits and potential risks of using ChatGPT and ethical considerations. This book is intended for anyone interested in natural language processing, machine learning, or artificial intelligence. We assume no prior knowledge of these subjects and aim to provide a clear and concise introduction to the topic. I hope this book will give readers a better understanding of ChatGPT, its capabilities, and limitations and inspire further research and development in natural language processing. Cheers! Author Dheeraj Mehrotra