A geographic information system (GIS) software package is basically a computer program designed to make a computer think that it’s a map. This new sort of map is a dynamic entity, designed to assist people in making decisions. Such decisions might be as simple and short range as determining an efficient way to get from place A to place B. Or as complex as designing a light rail transportation system for a city or delineating flood planes. The difference between a paper map and a GIS map is that the latter exhibits “intelligence.” You can ask it a question and get an answer.

Geographic information systems are transforming all the activities and disciplines that formerly used maps as the basis for decision making. It’s about time. Most fields of human endeavor have long since been heavily impacted by the digital computer; in fact it’s hard to think of one that hasn’t. Fifty years have gone by since computers began changing accounting, census taking, physical sciences, and communication, to name a few. Even the field of music has been altered. Most of these “nonspatial” fields already couched their problems in terms of discrete symbols (such as A, r, 5, and $) that are easily converted to the binary language (using only the symbols 0 and 1) that the computer understands. The spatial fields such as geography, planning, and land use management, had to stick with maps because, while maps also use symbols, they are not so neat and tidy as to fit on the keys of a keyboard. ...

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