A geographic information system (GIS) consists of integrated computer hardware and software that store, manage, analyze, edit, output, and visualize geographic data.[1][2] Much of this often happens within a spatial database, however, this is not essential to meet the definition of a GIS.[1] In a broader sense, one may consider such a system also to include human users and support staff, procedures and workflows, the body of knowledge of relevant concepts and methods, and institutional organizations.
The uncounted plural, geographic information systems, also abbreviated GIS, is the most common term for the industry and profession concerned with these systems. It is roughly synonymous with geoinformatics and part of the broader geospatial field, which also includes GPS, remote sensing, etc. Geographic information science, the academic discipline that studies these systems and their underlying geographic principles, may also be abbreviated as GIS, but the unambiguous GIScience is more common.[3] GIScience is often considered a subdiscipline of geography within the branch of technical geography.
History and development
While digital GIS dates to the mid-1960s, when Roger Tomlinson first coined the phrase "geographic information system",[5] many of the geographic concepts and methods that GIS automates date back decades earlier.
One of the first known instances in which spatial analysis was used came from the field of epidemiology in the "Rapport sur la marche et les effets du choléra dans Paris et le département de la Seine" (1832).[6] French geographer and cartographer, Charles Picquet created a map outlining the forty-eight Districts in Paris, using halftone color gradients, to provide a visual representation for the number of reported deaths due to cholera per every 1,000 inhabitants.
