Rating: 
Summary: A laudable effort. But the book is an enigma.
Review: A commendable effort. But I couldn't tell if Petzold set out to teach an introductory computing course to the non-technical reader or if he meant to include everbody. In either case, he will probably disappoint both camps. He is best when he introduces a topic with fascinating insights. But then he cannot resist giving computing lectures that are best left to a text book. A discussion of edge-triggered D-type flip flops and timing diagrams don't belong in a popular book.In the chapter on "Two Classic Microprocessors" I was hoping for a comparison of the Intel and Motorola architectures and how Motorola lost to Intel in the marketplace despite having a more elegant architecture. Instead, we get a boring treatise of the two instruction sets and sentences like "The 6800 doesn't have a Parity flag like the 8080, but it does have ... an Overflow flag". He might have been forgiven if he was using it to make the CISC vs. RISC case. Instead RISC gets only a cursory mention. I still like the book as a reference.
Rating: 
Summary: The Origin of the "Computer" Species
Review: Are you computer illiterate, or suffer with a near phobia about technology and its continuing advancement? Well then calm down and do yourself a favor and read this book! Petrzold writes well and has a good sense of humor. He wisely starts the book off with people who influence the design of the computer, and then goes into the basic mathematics the computer uses. If you don't know nothing about the computer (that includes if you don't know how to turn the computer on!) you will by the end. Relax and enjoy!
Rating: 
Summary: pretty good
Review: As a hobbyist programmer, I had wondered for years how a computer worked at its most internal level. I had even had a couple of unsuccessful encounters with other "How Computers Work"-type books that left me mainly with the dissatisfied impression that the machine was an impenetrable black box. Petzold's book was not like this. While other books started with flashy graphics of internal designs all flowcharts with little in the way of explanation, Code starts off simply, with two flashlights and the goal of communicating at night. This problem, of course, would be easy solved by anyone who knows of Morse code. Yet, from Petzold's pen it becomes an illuminating and amusing journey with attempts to deal with similar scenarios of every increasing complexity until I realized two-thirds of the way through that given a sufficient time and space, I could, at least in theory, build a computer. This is the greatest success of Code, in my opinion. Rather than attempting to peel away the mysteries of the system a layer at a time like an onion, it delves directly to the core and builds upon its ideas in a fashion like that of the original computer designers, until everything forms into a cohesive whole. Petzold does an excellent job of capturing his excitement for the material, making the progressive developments a joy to read about. With my uneven background knowledge, there were a few sections that I felt that I could skim through, but also many a passage that I had to carefully scrutinize. Overall, I'd recommend this book for anyone interested in computers, from beginner to expert: Petzold provides enough explanation for a determined newcomer to understand all of the concepts, but enough breadth to still entertain and educate those with more experience in the area.
Rating:
Summary: The Best Book of this Type
Review: As a hobbyist programmer, I had wondered for years how a computer worked at its most internal level. I had even had a couple of unsuccessful encounters with other "How Computers Work"-type books that left me mainly with the dissatisfied impression that the machine was an impenetrable black box. Petzold's book was not like this. While other books started with flashy graphics of internal designs all flowcharts with little in the way of explanation, Code starts off simply, with two flashlights and the goal of communicating at night. This problem, of course, would be easy solved by anyone who knows of Morse code. Yet, from Petzold's pen it becomes an illuminating and amusing journey with attempts to deal with similar scenarios of every increasing complexity until I realized two-thirds of the way through that given a sufficient time and space, I could, at least in theory, build a computer. This is the greatest success of Code, in my opinion. Rather than attempting to peel away the mysteries of the system a layer at a time like an onion, it delves directly to the core and builds upon its ideas in a fashion like that of the original computer designers, until everything forms into a cohesive whole. Petzold does an excellent job of capturing his excitement for the material, making the progressive developments a joy to read about. With my uneven background knowledge, there were a few sections that I felt that I could skim through, but also many a passage that I had to carefully scrutinize. Overall, I'd recommend this book for anyone interested in computers, from beginner to expert: Petzold provides enough explanation for a determined newcomer to understand all of the concepts, but enough breadth to still entertain and educate those with more experience in the area.
Rating:
Summary: Excellent
Review: As a merchant marine officer for many years I always enjoyed using a sextant and calculating some formulas to determine my position on the face of the earth to within a half mile. It just seemed like magic until one day I sat down and really thought about what was happening when I used a sextant and calculated these formulas, and finally it all made sense. I could see how there was a logical method to what initially seemed like magic. This book will reveal a similar enlightenment to the reader who feels that computers are magic (as I did). My only beef is that the book did not have a comprehensive index. That would have certainly been a big plus because I can see myself referring to this book in the future. Also, I kept waiting for an explanation of how a million transistors can fit onto a single silicon chip and it never came. Guess I'll have to find another book to explain that bit of "magic". But I recommend the book for anyone, neophyte or professional.
Rating:
Summary: Excellent
Review: As a merchant marine officer for many years I always enjoyed using a sextant and calculating some formulas to determine my position on the face of the earth to within a half mile. It just seemed like magic until one day I sat down and really thought about what was happening when I used a sextant and calculated these formulas, and finally it all made sense. I could see how there was a logical method to what initially seemed like magic. This book will reveal a similar enlightenment to the reader who feels that computers are magic (as I did). My only beef is that the book did not have a comprehensive index. That would have certainly been a big plus because I can see myself referring to this book in the future. Also, I kept waiting for an explanation of how a million transistors can fit onto a single silicon chip and it never came. Guess I'll have to find another book to explain that bit of "magic". But I recommend the book for anyone, neophyte or professional.
Rating:
Summary: A very good book to understand how a computer really works
Review: As the author states, this is not another book of how computers work. I had been looking for a book that explained how a microprocessor does what it does. And with this book I got that and much more. I should also say that this book is good only if you love computers, because otherwise, it would be a little bored, especially because it goes beyond software into hardware and talks a lot about digital electronics and logic gates. But to me, it is very very good and I recommend it to everyone who has a real interest in computers.
Rating:
Summary: An easy to follow historical and technical perspective
Review: Charles Petzold a does an outstanding job of explaining the basic workings of a computer. His story begins with a description of various ways of coding information including Braille, Morse code, and binary code. He then describes the development of hardware beginning with a description of the development of telegraph and relays. This leads into the development of transistors and logic gates and switches. Boolean logic is described and numerous electrical circuits are diagramed showing the electrical implementation of Boolean logic. The book describes circuits to add and subtract binary numbers. The development of hexadecimal code is described. Memory circuits are assembled by stringing logic gates together. Two basic microprocessors are described - the Intel 8080 and the Motorola 6800. Machine language, assembly language, and some higher level software languages are covered. There is a chapter on operating systems. This book provides a very nice historical perspective on the development of computers. It is entertaining and only rarely bogs down in technical detail.
Rating:
Summary: ¡Una obra maestra!
Review: Creo que es lo más didactico que leí en los últimos 5 años. El autor es una verdadero maestro, un educador de primera categoría. Esta obra es para todas las edades. Pero es especial para "acelerar" a los jovenes que quieren ingresar al fascinante mundo de la computación por la puerta de la Historia de la Ciencia.
Rating:
Summary: A wonderful and timely text!
Review: Excellent! excellent!! excellent!!! Kudos to Chuck Petzold for putting together a book which explains all the basics behind computer function. I need not say more...all the other reviewers have penned it nicely before me. A "must have" for anyone in this day and age.
| 
