Here's a straightforward answer to the question every parent has been asked, and few can answer: How do computers really work? Hillis, the head of Disney's Imagineering Works, begins by describing a stone etched in a complex pattern, which can be asked questions in a strange language and give profound and useful answers. It sounds like witchcraft, but it is a literally accurate description of a computer chip. As he goes on to show, the internal workings of a computer can be broken down into simple components. His first chapter introduces the reader to the rudiments of Boolean logic and simple electrical circuits. These ideas can be used to build simple computers, such as the author's own early design of a machine to play tic-tac-toe or another made from Tinker Toys. The next step in complexity is the development of specific logical functions--And, Or, Invert--that form the basis of almost all computing functions. These concepts are illustrated by the game Rock, Paper, Scissors, converted to digital form. Programming is illustrated with the famous ""turtle"" programs from the Logo computing language, designed to teach children. In similar manner, Hillis introduces the reader step by step to Turing machines, algorithms, encryption, and other advanced concepts. All this is done without discussions of state-of-the-art hardware or engineering problems; in fact, the author encourages the reader to think in terms of ""black box"" modulees that can be combined to perform a desired task. One need not know what's in the box as long as one knows its ultimate function. The final chapters look at issues on the frontiers of computing: machines that learn and adapt, possibly even (in time) machines that can be said to ""think."" All this is done elegantly and entertainingly, without a whiff of condescension toward the nontechnical reader. Clear and down-to-earth; even hopeless technophobes should find it enlightening.