Author: Tiana Laurence
Publisher: Wiley
Date: May 2017
Pages: 240
ISBN: 978-1119365594
Print: 1119365597
Kindle: B06ZY3YDDK
Audience: Non-technical users
Rating: 3
Reviewer: Alex Armstrong

The blockchain's best days are far from over, so why not read a book suitable for dummies?

This book isn't what is might appear to be. It isn't about the technology and after reading it it you probably won't know any more about how things work. As a dummy you are most likely going to be thrown by the use of unexplained words like "hash" and "merkle tree". There is a diagram of a merkle tree, but no explanation of what it is or how it works. At a slightly less technical level the introductory chapters have a tendency to use terms such as the Byzantine General's problem and similar.

OK, this is all fine as you might not buy the book to find out how the blockchain works - just to find out why you keep hearing about it. The problem is that the book doesn't really distinguish between the different algorithms used in association with the blockchain and the basic idea of a blockchain. It claims that the blockchain solves the problem of who you can trust and this isn't true in any sense.

The blockchain solves two  problems. The first is that it provides a way to create a public ledger that cannot be modified without that modification being noticed. The reason is that the blocks are linked together by cryptographic hashes which depend on blocks earlier in the chain. Any changes to the earlier blocks become immediately obvious as the chain becomes inconsistent. Why is this important to know? Because it indicates the essential properties of the blockchain. The deeper into a chain a block becomes the more it is fixed and unchangeable because changing it means rebuilding and revalidating the chain from that point on.

The issue of trust isn't part of the blockchain's main algorithm, but part of the proof of work algorithm, which addresses the second problem regarding trust. While the blockchain doesn't prove that you can trust the person elected to validate the block. It does provide a trustworthy way of selecting that agent. The agent you select could be corrupt, but there is no way that any corrupt agents can manipulate the selection procedure so that they are certain to be selected to mal-administer the blockchain.

OK, that's the blockchain in a nutshell and this book doesn't tell you this.

What the book does do is to give you some very rough ideas of what a blockchain is and then takes you through some examples.  Chapter 1 is an introduction to the ideas of the blockchain and in many ways this is about as technical as the book gets. Chapter 2 is about picking a blockchain and is a vague management guide. Chapter 3 tells you how to get a bitcoin, use a wallet and what a smart contract is. Its final few pages explain Ethereum.

Part 2 of the book is a tour of using different blockchains. Chapter 4 describes the Bitcoin blockchain, which is where it all started. From here we have chapters on Ethereum, Ripple, Factom (the author's own company) and DigiByte. Then in Part 3 the tour continues with Hyperledger, Azure and IBM Bluemix. Each is more or less a user's guide rather than being deep and technical.

The fourth part of the book deals with application areas. We have chapters on financial technology, real estate, insurance and government and a final one on other smaller areas.

The final part will seem a little strange if you are not familiar with other books in the For Dummies series. Called The Part of Tens it consists of three chapters that each list ten things - ten resources, ten rules and ten projects. This is part of the standard format and seems to work in this case. 

I also have to agree with other reviewers that there are a lot of distracting typos and these make reading the book harder.

I can't say I enjoyed reading this book, but this is mostly because I like tech and I wanted to have the tech explained to me. You might like it more if all you want it a sort of guided tour of the landscape of the blockchain. The problem really is that if you are going to innovate then to see the possibilities is something you first have to understand. This book partly equips you to get into the world of the blockchain as it is, but not to think of radical new ways it could be used.

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