There are several conventions that are used in this book to try and make your learning experience easier. These are explained here.
This icon is used to flag notes or advice from the authors to you, the reader. For instance, if there is a particular topic or concept that you really need to understand for the exam, or if there's something that you need to keep in mind while working, you will find it set off from the main text like this.
This icon is used to flag tips or especially helpful tricks that will save you time or trouble. For instance, if there is a shortcut for performing a particular task or a method that the authors have found useful, you will find it set off from the main text like this.
Computers are delicate creatures and can be damaged easily. Likewise, they can be dangerous to work on if you're not careful. This icon is used to flag information and precautions that will not only save you headaches in the long run; they may even save you or your computer from harm.
This icon is used to flag passages in which there is a reference to the book's companion Web site, which is located at http://authors.phptr.com/rosenzweig3e.