TABLE OF CONTENTS What is a Computer? A simple question with no easy answer a conventional engineering definition is that a computer is first and foremost a tool, not an object, i.e. a computer is defined not by what it is but rather by what it does. But let s take a different course.
In the early days, computers were behemoth machines that carried out elaborate mathematical calculations. Programs were written to perform a desired calculation, submitted to the room-sized computer, and then you waited while the machine crunched your numbers and printed the results onto several reams of wide green-striped paper.
The next evolution raised the computer out of the big mainframe, batch-oriented, number-cruncher category into what were called microcomputers because these new machines were smaller versions of the older, bigger mainframes.
That brings us to the modern computer a device that can be as small as your hand or as large as a small suitcase. It comes with a CPU, some RAM, an address bus, data bus, and so forth. The central focus of today s computers is interactivity. Their very essence is to explore. The human uses his or her creativity and values to propose a variation on an existing scheme. The computer uses its computational resources to work out the ramifications of the variation and presents the resultant order of things to the human. Today computers responses are so fast that humans are encouraged to try again and again, with different variations, to explore all the possibilities, to...
