Britannica Sources used in this answer

How do geographic information systems use digital maps to display data patterns?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

information system A woman taking a driver's license test on a computer, an example of a government using an information system to provide services to citizens.

A Geographic Information System (GIS) uses digital maps to display data patterns by organizing information into thematic layers, themes, or coverages. These layers function similarly to historical transparent overlays, allowing users to store, compare, and analyze specific geographic content—such as population density, soil, or hydrology—within a single spatial area.1

GIS stores these graphic elements using two primary computer graphic formats:

Vector-based GIS: Represents entities as coordinate pairs (points), lines, or areas, often using a Triangulated Irregular Network (TIN) to model topographic surfaces.1
Raster-based GIS: Represents data as a matrix of uniform grid cells, such as a digital elevation model (DEM).1

By linking geographic entities to descriptive attributes, GIS operators use algorithms to manipulate these layers. This enables the simulation of complex patterns, such as traffic flows or resource management, through cartographic modeling, providing actionable insights for urban planning and environmental analysis.1