This book is dedicated to all those interested in learning something new about information and communication technology. My experiences over the past thirteen years as a professional teacher and author in the field of information and communication technology have led to the creation of this book. My students have always encouraged me to put the interesting and rewarding lectures I have given them into written form. For schools and institutions looking for a study guide or a compilation of fundamental computer principles for their students, and preparing for some internal or external exams, you have found the right book to excel. This book is carefully divided into parts and sections to provide readers and students sitting for exams, or workers eager to improve or acquire new skills for promotion at their workplace, with easy access and understanding.