Conventions

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: "The index.php file now yields this result".

A block of code is set as follows:

<?php 
 
abstract class Notifier 
{ 
 protected $to; 
 
 public function __construct(string $to) 
 { 
 $this->to = $to; 
 } 
 
 abstract public function validateTo(): bool; 
 
 abstract public function sendNotification(): string; 
 
}

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

echo $richard->hasPaws;

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: "direct your web browser to your chosen web server and you should see Hello world! pop up on screen."

Note

Warnings or important notes appear in a box like this.

Tip

Tips and tricks appear like this.