It was July of 1958. . ."" ""It was January of 1959. . ."" And so, in breezy closeups, Washington Post reporter Reid introduces two engineer-heroes of the computer world: Robert Noyce, then of Fairchild and now of Intel, and Jack Kilby, a freelance after years of association with Texas Instruments. What they did was solve a problem called the ""Tyranny of Numbers""--or how to wire together all the necessary transistors, capacitors, resistors, to make the circuits that are the guts of a computer, and make them amah and reliable. The answer was the integrated circuit. You used the sliver of silicon doped in such a way that parts could function as transistors, etc., and you laid down the connections between the components by etching the sliver with a conducting element. Kilby got the essential idea of using one silicon wafer for the whole circuit. Noyce got the idea of etching it. And it took ten years of fighting by the patent lawyers of their parent companies to resolve the rights. In the end, Texas Instruments and Fairchild decided to split the licensing fees, to the great good fortune of both. Noyce, the image of entrepreneurial dynamism, went on to form Intel and develop random access memory chips. Kilby went on at TI to develop the first hand-held calculators. Expanding upon microelectronics-industry history, Reid neatly sketches in the key personalities and provides surprising detail on the algebra and logic circuits of computers. His focus on the essential engineering problems, on the role of the Defense Department and NASA (bent on getting the lightest weight and volume of computers to be used in space), also complements other approaches--including that of John Case (above). Topical material, smartly presented.