Geographic I 6 . Geographic Information Systems

Before addressing the diverse functionalities that can be found in Geographic Information Systems (GIS) today, a definition of a geographic information system, its purpose, and its general architecture shall be given. The different forms of GIS that are found in today’s ever-expanding range of information technology tools will therefore be discussed in Sect. 6.1. The core of each GIS is constituted by analysis functions. They are the reason why a GIS is created in the first place. The last section in this chapter (Sect. 6.2) contains a list of the most common GIS functionality categories. A few typical examples of such analysis functions are described in more detail, to explain what geographic information (GI) is all about and how its digital form can be utilized to solve problems of geospatial nature efficiently, to gain insight into the processes of geospatial nature that influence many aspects of our life, and to arrive at decisions that are sound, explainable, and repeatable. 6.1 Architecture of a GIS ............................. 145 6.1.1 Information and Data ................... 145 6.1.2 Geographic (Geospatial) Information................................. 147 6.1.3 Geographic Information System Definitions .................................. 147 6.1.4 Classical GIS and Recent Modifications .............. 148