ABSTRACT
What makes GIS special? Most people who work with geographic information systems have asked themselves this question at one time or another. This chapter starts to answer the question by describing the field of GIS against the general background of computing. First, we define the terms“information system” and “GIS,” identifying what distinguishes geographic information systems from other information systems. The discussion outlines the main functions of a GIS, with a particular emphasis on those vital functions provided by the database (Section 1.1). Then, in Section 1.2, we look at what we can do with a GIS. Presenting some typical, example applications provides a motivation for studying GIS. Spatial data plays a key role in any application of GIS, as do the different ways we use that data to model the world around us, explored in Section 1.3. The fundamental computing technologies and concepts that enable GIS are briefly introduced in Section 1.4. Taking a step back, the chapter concludes with an analysis of what makes spatial—not just GIS—special (Section 1.5).
