This book provides an accessible and in-depth introduction to data protection and encryption, two topics with significant social and political significance. It explains what algorithms do, how they’re employed, the dangers involved, and why governments should be worried. Important topics are highlighted, including digital signatures, stream ciphers, block ciphers, public key algorithms, and e-commerce applications. This book emphasizes the enormous influence of encryption on contemporary culture, including the development of the internet and the adoption of more advanced financial techniques.