Throughout the book, I occasionally provide you with boxed asides, tips that should serve as little reminders or simpler ways to do things.
You'll also notice boxes that start out with the phrase "Shell out." Although I intend to concentrate on working with graphical tools and in a graphical way, much of the power of Linux comes from working with the command line, or the shell. The Shell Out boxes will guide you in working with the shell.
Learning to wield the command line is akin to getting a black belt in a martial art or earning a first aid certificate. It doesn't mean that you are going to run out and take on all comers or that you are going to be facing daily crisis situations. Working with the shell does give you the means and the confidence to step outside the confines of the graphical environment. The shell is power, and it is always there for you, so you should not fear it.