This book fills the gap that exists between purely technical books about the blockchain, on the one hand, and the literature that is mostly concerned with specific applications or discussions about its expected economic impact or visions about its future, on the other hand. The blockchain has received a lot of attention in the public discussion and in the media. Some enthusiasts claim that the blockchain is the biggest invention since the emergence of the Internet. Hence, a lot of books and articles have been written in the past few years about the blockchain. However, if you want to learn more about how the blockchain works, you may find yourself lost in a universe of books that either quickly skim over the technical details or that discuss the underlying technical concepts at a highly formal level. The former may leave you unsatisfied because they miss to explain the technical details necessary to understand and appreciate the blockchain, while the latter may leave you unsatisfied because they already require the knowledge you want to acquire