This book provides an essential compilation of relevant and cutting edge academic and industry work on key Blockchain topics. This book concentrates on a wide range of advances related to Blockchains which include, among others, Blockchain principles, architecture and concepts with emphasis on key and innovative theories, methodologies, schemes and technologies of Blockchain, Blockchain platforms and architecture, Blockchain protocols, sensors and devices for Blockchain, Blockchain foundations, and reliability analysis of Blockchain-based systems.  Further, it provides a glimpse of future directions where cybersecurity applications are headed. The book is a rich collection of carefully selected and reviewed manuscripts written by diverse cybersecurity application experts in the listed fields and edited by prominent cybersecurity applications researchers and specialists.