The book is fine, listing loads of different things that you may need to reference. Those studying A+ or similar courses may find this book useful whenever new terms arise - it's quite well set out, and covers a lot of subjects.
My only gripe is that it seems the Americans invented everything according to this book!
Major milestones such as the early British computers (colossus etc)are skipped, and the American WW2 machines are credited with being the first 'computers' - there's plenty of other things like this as well.
It doesn't particularly matter as far as using the book as a simple technical reference, but I wouldn't want to write a history of the computer based on this book!
I think that if any sort of history is included in these sort of technical books, it should be done correctly - instead of pampering to the home crowd. (Can anyone say Microsoft Encarta?!)