Perhaps, steganography emerged in ancient times as a dark magic, but certainly, it evolved during the computer age at large. Currently, it has many techniques, methods, and applications, making it worth having a closer look at. This book presents a comprehensive overview on steganography and on its different techniques that have been proposed in the literature during the last decades. It additionally sheds the light on its history before and after the advent of digital computers, its various algorithms, requirements, and processes