This book uses some typographic conventions that can help you navigate through the text easily. When you see certain kinds of typefaces, you’ll know they have special meanings:
Used to show arguments and variables that should be replaced with user-supplied values. Italic is also used to indicate filenames and directories and to highlight comments in examples.
Constant Width
Used to show the contents of files or the output from commands.
Constant Width Bold
Used in examples to show commands or other text that should be typed literally by the user.
Constant Width Italic
Used in examples to show text that should be replaced with user-supplied values.