If you have friends or relatives who wonder how exactly computers work, here is a book to offer them which has probably the most lucid explanations that I’ve ever read on the foundations of computer science. This short book will not help neophytes distinguish between RAM and ROM-we have Wikipedia for that-but it’s hard to imagine more accessible explanations for laymen on subjects like Boolean algebra, multiprocessors and artificial intelligence. I can also imagine this book be great supplement for the general education of university-level computer science students. The real strength of Danny Hillis‘s approach is how he is able to simplify abstractions using everyday concepts and experiences to illustrate the higher-level ideas behind modern computers, hardly an easy task. The Pattern on the Stone is available at Amazon at the moment for $11.20.