the development of automated mapping systems. Their research on map reading processes, map production techniques, cartographic generalization, and cartographic design has facilitated the automation and formalization of what had been an intuitive manual procedure. With generalization, for example, a conceptual model has been devised that separates the subjective and holistic approaches of traditional cartography into discrete subcomponents that have been successfully incorporated into digital mapping software (McMaster and Shea, 1992). Cartographers have also worked to prevent the inadvertent misuse of computer mapping systems and maps by developing expert systems for map production.
Some of the most interesting and potentially useful research conducted by geographers today is in the realm of dynamic or animated cartography. Animation enables the visualization of changes in phenomena across space, through time, and in attributes of the phenomena themselves (see Sidebar 4.3). One of the earliest animated maps of the microcomputer era showed the spread of AIDS at the county level in Pennsylvania (Gould, 1989). This animation was used to highlight the initial concentrations and spatial diffusion of the disease more effectively than a sequence of static maps. The intention of this dramatic portrayal was to inform and educate health care researchers and the general population. The cartographic techniques developed in this research subsequently led to inclusion of a series of animated maps in one of the best-selling CD-ROM encyclopedias.
Geographers have led the way in research on another new cartographic format: electronic atlases and atlases on CD-ROMs. In a recent project undertaken jointly by Florida State University, the Florida Department of Education, and IBM, an atlas of Florida was published on a CD-ROM and distributed to all schools in the state ("Atlas of Florida," 1994; see Figure 4.5). This format permits the inclusion of multimedia material that could not be accommodated by traditional printed text: audio, video, animation, or a multitude of photographs and other graphics. Electronic atlases and related geographic programs are already proving to be effective in educational settings, especially at the kindergarten through grade 12 levels. The newly released "ExplOregon: A Geographic Tour of Oregon" (a 1995 multimedia CD-ROM developed by William Loy with Digital Chisel software by Pierian Spring Software) is changing the way that the geography of Oregon is taught and learned in schools throughout the state. As national standards for geography education are developed, educational aids such as electronic atlases will become indispensable.
Geographic information systems were defined in 1992 by the U.S. Geological Survey as "computer system[s] capable of assembling, storing, manipulating, and displaying geographically referenced information" (USGS, 1992). Such systems, in fact, have power, utility, and importance far beyond this definition, both within and beyond the field of geography. Their most valuable potential capability,