The following typographic conventions are used in this book:
Used for file and directory names, email addresses, and URLs, as well as for new terms where they are defined.
Used for code listings and for keywords, variables, functions, command options, parameters, class names, and HTML tags where they appear in the text.
Constant Width Bold
Used to mark lines of output in code listings.
Used as a general placeholder to indicate items that should be replaced by actual values in your own programs.