The book assumes you already have basic knowledge of JavaScript, and works up from there. Modern features of the language are explained, so we can develop code in the best way. Best practices for the language are also introduced and followed in all the code. Knowledge of HTML and CSS will also be required for the web and mobile applications.

All the code in the book runs on Windows, macOS, and Linux machines, so you shouldn't have any problems with regard to whatever computer you use. Some experience with terminal/command-line tools will come in handy, but most of the work will be done with a graphic interface.

You can download the example code files for this book from your account at www.packtpub.com. If you purchased this book elsewhere, you can visit www.packtpub.com/support and register to have the files emailed directly to you.

You can download the code files by following these steps:

1. Log in or register at www.packtpub.com.
2. Select the SUPPORT tab.
3. Click on Code Downloads & Errata.
4. Enter the name of the book in the Search box and follow the onscreen instructions.

Once the file is downloaded, please make sure that you unzip or extract the folder using the latest version of:

• WinRAR/7-Zip for Windows
• Zipeg/iZip/UnRarX for Mac
• 7-Zip/PeaZip for Linux

The code bundle for the book is also hosted on GitHub at https://github.com/PacktPublishing/Modern-JavaScript-Web-Development-Cookbook. In case there's an update to the code, it will be updated on the existing GitHub repository.

We also have other code bundles from our rich catalog of books and videos available at https://github.com/PacktPublishing/. Check them out!

We also provide a PDF file that has color images of the screenshots/diagrams used in this book. You can download it here: https://www.packtpub.com/sites/default/files/downloads/9781788992749_ColorImages.pdf.

There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: "Keep in mind that you won't always be needing util.promisify()."

A block of code is set as follows:

// Source file: src/roundmath.js

/* @flow */
"use strict";

// continues..

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

// Source file: src/flowcomments.js

let someFlag /*: boolean */;
let greatTotal /*: number */;
let firstName /*: string */;

function toString(x /*: number */) /*: string */ {
    return String(x);
}

let traffic /*: "red" | "amber" | "green" */;

// continues...

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

> npm install moment --save
> npm run addTypes

Bold: Indicates a new term, an important word, or words that you see on screen. For example, words in menus or dialog boxes appear in the text like this. Here is an example: "VSC provides full access to commands through its Command Palette... as seen in the following screenshot."