Sometimes in technical books, people skip the Getting help heading. Don't skip this one! It's very important, and will save you a lot of time and confusion.
You can get help on using most of the commands in this book with a two-step process. When you're using Bash, to get help on a command named printf, use help first:
bash$ help printf
You'll get some help output, so you now know that printf is a Bash keyword or builtin. That's the version of the command you want help with, because that's the one that you'll be using when you call it from within Bash.
To see why this is confusing, try the man manual reader command, instead:
bash$ man printf
You'll get a completely different document, a full manual page! The features ...
