PROGRAMMERS USE THE WORD "TOOLS" OVER AND OVER to describe both the software they create and the programming implements they use. To speak of tools is to adopt the language and the perspective of the craftsman and the engineer. Programmers labor in the field of"computer science," but it may be a misnomer. "It's an engineering discipline, not a scientific discipline," noted Fred Brooks, the software engineering expert. The two perspectives are quite different. The scientist builds in order to study, Brooks explains, while the engineer studies in order to build.
Many leading programmers fell into software from science or mathematics, after they found greater appeal in the practical tools of software than in the theory of other fields. Butler Lampson, whose research at Xerox PARC helped lay the foundation for the modern personal computer, described the conversion experience. During the 1960s, he was studying for his doctorate in physics at Berkeley, but one day he walked into the university's computer lab and never returned to physics. "I stumbled in there, and got sucked into computing," he recalled. And like so many physicists and mathematicians who lapsed into computing, Lampson speaks of the satisfactions of engineering - of making things with software, a building material that requires only intellect to assemble, not armies of workers or trucks and cranes to hoist. Programming, Lampson says, is free-range engineering. "Engineers get their kicks out of building things. That's the drug for just about anyone who has gotten hooked on computing."
As this book is being finished, the next evolutionary step in computing is coming into view. It has been dubbed "grid" computing, suggesting that intelligent computer power will someday be available to people like a utility, assisting people whenever and wherever it is needed - just plug in or tap in wire‐ lessly, and the power of a supercomputer will be available. In many ways, the grid concept is remarkably familiar, echoing J. C. R. Licklider's vision of "man—machine symbiosis" and the information utility idea dating back to the