Chapter 1, Understanding Decentralized Applications, will explain what DApps are and provide an an overview of how they work.

Chapter 2, Understanding How Ethereum Works, explains how Ethereum works.

Chapter 3, Writing Smart Contracts, shows how to write smart contracts and use geth's interactive console to deploy and broadcast transactions using web3.js.  

Chapter 4, Getting Started with web3.js, introduces web3js and how to import, connect to geth, and explains use it in Node.js or client-side JavaScript.

Chapter 5, Building a Wallet Service, explains how to build a wallet service that users can create and manage Ethereum Wallets easily, even offline. We will specifically use the LightWallet library to achieve this.

Chapter 6, Building a Smart Contract Deployment Platform, shows how to compile smart contracts using web3.js and deploy it using web3.js and EthereumJS.

Chapter 7, Building a Betting App, explains how to use Oraclize to make HTTP requests from Ethereum smart contracts to access data from World Wide Web. We will also learn how to access files stored in IPFS, use the strings library to work with strings, and more. 

Chapter 8, Building Enterprise Level Smart Contracts, explains how to use Truffle, which makes it easy to build enterprise-level DApps. We will learn about Truffle by building an alt-coin.

Chapter 9, Building a Consortium Blockchain, we will discuss consortium blockchain.

You require Windows 7 SP1+, 8, 10 or Mac OS X 10.8+.

This book is for JavaScript developers who now want to create tamper-proof data (and transaction) applications using Blockchain and Ethereum. Those who are interested in cryptocurrencies and the logic and database empowering it will find this book extremely useful.

In this book, you will find a number of text styles that distinguish between different kinds of information. Here are some examples of these styles and an explanation of their meaning.

Code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles are shown as follows: "Then, run the app using the node app.js command inside the Final directory."

A block of code is set as follows:

var solc = require("solc"); 
var input = "contract x { function g() {} }"; 
var output = solc.compile(input, 1); // 1 activates the optimizer  
for (var contractName in output.contracts) { 
    // logging code and ABI  
    console.log(contractName + ": " + output.contracts[contractName].bytecode); 
    console.log(contractName + "; " + JSON.parse(output.contracts[contractName].interface)); 
}

Any command-line input or output is written as follows:

npm install -g solc

New terms and important words are shown in bold. Words that you see on the screen, for example, in menus or dialog boxes, appear in the text like this: "Now select the same file again and click on the Get Info button."

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