Book excerpt: Blockchain technology has come a long way since the initial vision published by Satoshi Nakamoto in 2008. Big buzz words like "bitcoin," "blockchain," and "cryptocurrency" are everywhere. Companies and governments have started to use blockchain technology in earnest and will increasingly do so for the foreseeable future. This book takes an in-depth look at blockchain technology and how users can take advantage of its potential. Since its initial conception, blockchain has encompassed both a social promise and new technology. Originally proposed as a solution for Bitcoin's cryptocurrency record-keeping system, blockchains are now used to store the records of all types of applications. Core services we all depend on like the transfer of money, voting, land records, IP rights, and identity all rely on intermediaries. Blockchain software has begun taking the place of these antiquated systems. The software becomes the trusted record-keeping system, and the rules programed into the software become the intermediaries. This book explains the fundamentals of blockchain technology and assumes that the reader has little to no knowledge of the subject. Topics are explained as simply as possible, while not obscuring details that may affect the reader. It also gives the reader insight into the critical differences in blockchain software and will provide them with a basic understanding of how and why these systems work. After reading this book, the reader will be able to speak with confidence on the topic, know key differences in technology. The reader will also have critical insight into blockchain software's inherent limitations and shortcomings. This book is also the definitive guide to the Blockchain Technology Foundation (BTF) exam from EXIN. It will prepare the reader for the test, and each chapter ends with review questions for extra guidance in preparing for the exam.