A rarity: Kleinberg is a corporate computer engineer with a sense of humor. He knows that computers are no better than they ought to be--very fast logic machines. Non-thinkers. Devoid of flair, Spirit. Imagination. In this breezy but serious exposition Kleinberg explains the key design elements common to all digital computers: their logical ""AND,"" ""OR"" and ""NOT"" circuits, their binary codes, memories, program inputs and outputs. Unlike most popularizers he takes great pains to explain what a logical circuit is and how a computer performs its functions. (It is essentially an adder and Kleinberg explains how it even subtracts by adding--using ""complements of 9."") At times his drollery is forced and he labors a point. For example, he overuses his pet notion of a three-dimensional ""K vector""--a composite of logic, emotion, and intuition--to describe human thought. That makes human brains at least two dimensions richer than machines. Overall he is successful in his intent to explain, clarify, debunk. He also has some telling points to make about the potential dangers of computers as human data banks. He suggests we be wary but he aware that the IRS, Social Security, and countless other public and private agencies long preceded the machine in invading our privacy. A satisfying and knowledgeable little book, painless in its exposition for the non-math reader but with enough sophistication to appeal to those more in the know.