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: "For the purpose of this recipe, it is assumed that all the downloads will be stored on Windows in your personal C:Users<username>Downloads folder, or if using an OS X system, in the /Users/<username>/Downloads folder."

A block of code is set as follows:

<?xml version="1.0" encoding="utf-8"?>
<service>
  <description>enable FTPS ports</description>
  <port protocol="tcp" port="40000-40100"/>
  <port protocol="tcp" port="21"/>
  <module name="nf_conntrack_ftp"/>
</service>

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

sudo diskutil unmountDisk /dev/disk3
sudo dd if=./CentOS-7-x86_64-Minimal-XXXX.iso of=/dev/disk3 bs=1M

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: "Clicking the Next button moves you to the next screen."