Textbook in PDF format Computer Science Why is a book that presents a straightforward, curiosity?based approach to filling in the blanks around common, introductory material taught in Computer Science (CS) classes. If you have ever wondered "why is that?" about a programming phenomenon, historical tidbit, or common terminology, this book may have an answer that explains it. Undergraduate students learning various topics in Computer Science (CS) will encounter all sorts of conventional, prescriptive knowledge which they often must learn and memorize by rote force. Oftentimes, this knowledge is structured upon low-level, architecturally deep, and historical foundations that are impossible to fully convey and explain in introductory classes. Students must make do in learning numerous contexts without any additional context for the term or concept (the “why” of it). This book provides a clearer “why” behind many CS topics, so that instead of simply memorizing terms, the reader will be able to understand and utilize their context. Take any example in this book, from Bluetooth to floating point math to time zones, and you will read an answer that cements your insight on the “why” of the topic. The idea is to replace memorization with insight. Our charter in writing this book was simple: encourage students to expand their understanding of CS both by presenting the questions many are hesitant to ask in class, and then by shedding light on CS internals with the answers. We provide an answer that provides a revealing “ah-ha!” moment—specific, digestible explanations that an undergraduate CS reader can not just remember, but also use. Once you read the answers we have provided here, the reasons behind the topics are, we believe, plain yet vibrant and unforgettable. This book is not a replacement for CS course, work, or study. It supplements them. It is intended to augment those textbooks and other reference books and manuals. It is, however, freestanding as a source of answers and insights. It can be used on its own, but we intentionally made the answers only one layer deep. Thus, each answer is only the answer to the specific question, although some answers (and questions) raise other questions (and answers). Questions include Why do computers have trouble with floating point numbers? Why is it called Bluetooth? Why does it use that symbol? Why is it called bootstrapping? Why don’t modifications to function parameters persist once the function returns? Why do we use the QWERTY keyboard? … and many more Perfect for both students and IT professionals, this book provides the clear "why" to answer so many unstated CS questions. Take any example in this book, from base 2 to time zones, and you will have an answer that cements your insight on the "why" of the topic, reinforcing your rote memorization with deeper understanding and insight. Preface Introduction History Infrastructure Networking and Security Programming