An AnalogyImagine an overhead projector, with a series of transparencies laid upon it. Each transparency is about your town, drawn to the same scale, and can therefore be integrated with the others. But each transparency deals with a different topic: roads, places, earthquakes, census divisions, soil landscape data, and ecological zones:
Standing before the overhead, you mix and match the layers at will, magically changing classification schemes, modifying symbols, colors, patterns, and combinations. You can zoom in and out, seeing all the information available or only the data you specify, comparing this layer with that feature, exploring the data in every way imaginable. As you play with these layers of information, relationships appear. This is sort of what GIS is like. Through the power of a computer and software, using a wide range of electronic data, and with an eye toward patterns and relationships, GIS users explore information about places. Through creative questioning, careful analysis, and even random exploration, GIS users learn the patterns of people, objects, and features of one site, how they interact, and how one region influences another. In short, GIS is a tool for learning about the world and all that is in it. |
