Education is an all-important goal in life and should always be approached with eagerness and earnestness. We would like to show appreciation to the teachers who inspired us; you can always remember the teachers who touched your life, and to them we say thanks. We would also like to thank all of our students, who taught us a lot during the course of our many combined academic years.

Special thanks go to Mariann Barsolo, Kim Beaudet, Rebecca Anderson, and Pete Gaughan, our editors at Sybex who have been professional, courteous, and ever patient. Our appreciation also goes to technical editor Jon McFarland, who worked hard to make sure this book is of the utmost quality. We could not have done this revision without their help.

In addition, thanks to Dariush’s mother and brother for their love and support, not to mention the life-saving babysitting services.