What are "Geometries" in the context of GIS?

In the context of Geographic Information Systems (GIS), geometries refer to the mathematical expressions that describe spatial features, which include points, lines, and polygons. These geometries serve as fundamental building blocks for representing real-world entities in a GIS environment.

For example, a point geometry might represent a specific location such as a city or a landmark, while a line geometry can depict features like roads or rivers. Polygon geometries are used for areas such as lakes or administrative boundaries. Each type of geometry provides a structured way to define where features are located and how they relate to one another in a spatial context.

This definition is crucial because, in GIS applications, all spatial analyses and visualizations are based on these geometric representations. The mathematical nature of these expressions allows for various operations such as measuring distance, calculating areas, and performing spatial queries—all essential tasks in GIS applications. Understanding geometries enables users to accurately represent and analyze spatial data effectively.