Cartography is the visual representation and communication of data, geospatial information, and relationships in the form of printed and digital maps. The form of the map and the visual systems of map-making are determined by technologies of production and reproduction. The mass reproduction of maps has encouraged the dissemination of geospatial information, statistical data, and shared cultural and scientific understandings throughout history.
Maps as historical documents provide evidence of worldviews, cultural values, relationships, and representational practices at specific moments in time. Cartographic history encompasses the changing forms of the map as artifact. Ptolemy’s Geographia (2nd century ad), for example, records ancient Greek geographical concepts, and established conventions for representing geographic concepts including latitude, longitude, and north orientation. Mercator’s (1569) projection became a well-understood way to translate the globe to a two-dimensional chart (Harley & Woodward 1987).
Design processes for mapping data include reduction/simplification, scaling, projection (converting three-dimensional data into two-dimensional representations), symbolization, assemblage, and execution. These require systems of graphic and geographic conventions, including design elements and symbols (points, lines, areas, text, and color), hierarchies, and layers of information (MacEachren 1995; Wood & Keller 1996).
In the twentieth century cartography has been positioned as a science and an art of communication. The lineal model of communication placed an early emphasis on scientific efficiency. A shift of research attention by the 1970s to the map user and the nonlinearity of visual information processing saw both visual cognition and semiotic theory playing an important role in cartographic research and practice (Salitchev 1983). The rise of geographic information science (GIS) and geospatial computing in the 1980s concentrated attention on cartographic visualization processes and products in new technological environments. Early twenty-first-century research agenda have included map user experience and design issues in interactive, multimedia, web-based, mobile telecommunication devices and virtual cartographic environments.
A wider interdisciplinary concern with cartography and mapping in the later twentieth century has examined the cultural and constructed nature of the map as representational text. The concept and process of mapping is a mode of visual language and thinking equivalent to writing that enables a visual and spatial representation of abstract ideas, relationships, and understanding. Maps are thus understood as constructed texts, which interpret and present data in accordance with defined communication objectives and audiences (Crampton 2001; Harley 2001).
The cartography literature groups maps into two broad categories: topographical maps and thematic maps. Salitchev (1983) identifies three main uses of topographical and thematic maps: communicative use (i.e., storage, display, and dissemination of data); operative use (i.e., geographical management or navigational uses); and cognitive use (i.e., space–time investigations and visual display of phenomena).
Topographical maps and charts aim to construct an accurate symbolic representation of what exists in physical geographical worlds. Sometimes also described as general or reference maps (Robinson 1982), topographical maps rely on the quality of survey and other geographic data for accuracy of positions and relationships. Graphic symbols used in topographic maps include points, lines, areas, and text. The growth in production of topographic maps is associated with exploration and global discoveries in the sixteenth and seventeenth centuries; the invention and expansion of technologies of visual reproduction; the progressive advance of data capture and survey technologies; the worldwide military demand for geospatial information; and the subsequent expansion of empires and shifting national boundaries.
Thematic maps, also called data maps (Tufte 1983), visually represent all kinds of geographic, political, social, cultural, and economic data and relationships. Graphic symbols and conventions are used to represent the characteristics, patterns, distributions, differences, and changes over time of these phenomena, which include for example populations, routes, territories, and resources. The thematic map in the twentieth century has developed following the growth of quantitative geography and the production of geospatial data; the need for the visual presentation of scientific information; the development of statistics; the growth of information design; applied semiotics; and the centrality of the visual as the late twentieth-century mode of communication.
Since the advent of printing technologies enabling visual reproduction, maps have been produced for dissemination as a reference authority. Cartographic design and production bear a close historical relationship to both the technologies of visual reproduction and those of data capture. Reproduction technologies have included hand drawing; intaglio printing methods; photographic, photolithographic, and digital printing processes; and now screen-based media.
GIS (geographic information systems/science) have precipitated significant shifts in the production, function, dissemination, and uses of maps. These technologies have enabled network distribution, database linkages, interactivity, and new modes of visualization. The term cybercartography describes the intersection of geospatial visualization with digital and remote sensing technologies (Taylor 2005). Accompanying the rise in the technological expansion of cartography through GIS has been an interest by critical social theorists in the social and political implications of these technologies.
- Crampton, J. W. (2001). Maps as social constructions: Power, communication and visualisation. Progress in Human Geography, 25(2), 235 –252.
- Harley, J. B. (2001). The new nature of maps: Essays in the history of cartography. Baltimore, MD: Johns Hopkins University Press.
- Harley, J. B., & Woodward, D. (eds.) (1987). The history of cartography. Chicago and London: University of Chicago Press.
- MacEachren, A. M. (1995). How maps work: Representation, visualisation and design. New York: Guilford.
- Robinson, A. H. (1982). Early thematic mapping in the history of cartography. Chicago: University of Chicago Press.
- Salitchev, K. A. (1983). Cartographic communication: A theoretical survey. In D. R. F. Taylor (ed.), Graphic communication and design in contemporary cartography. Chichester: John Wiley.
- Taylor, D. R. F. (ed.) (2005). Cybercartograpy: Theory and practice. Amsterdam and Boston: Elsevier.
- Tufte, E. R. (1983). The visual display of quantitative information. Cheshire, CT: Graphics Press.
- Wood, C. H., & Keller, C. P. (1996). Cartographic design: Theoretical and practical perspectives. Chichester: John Wiley.