It unfortunately mixes good information with factual carelessness. The early British and American computers used relays, not tubes, a fact that is tacitly admitted when it comes time to try to explain how logic circuits work. Even more unfortunately, the explanations of the technology don't always explain real functions. Having presented relays and the term Boolean algebra, for example, the book then states that logic can be used for data manipulation, but not how. The construction of a simple two-bit adder would have expanded the length of the book by perhaps three pages, but would have demonstrated the concepts, rather than merely asserting them.
Most chapters end with a very short glossary of related terms and vocabulary.
Although it hardly seems possible, the discussion of software, in chapter two, is even worse. A historical, rather than analytical, account, the material doesn't even seem to be as informative as trivia, and asserts questionable opinions as fact. Similarly, genetic engineering gets a good overview in chapter five. Chapter six is a brief look at molecular biology, and falls back into stating what the technology might be able to do, but not how. Much the same is true of the longer chapter seven, looking primarily at diagnostic imaging with a short mention of bionics.