Geographic Information System — software and methods for capturing, storing, analyzing, and displaying spatial data.
GIS enables users to work with data that has a geographic component — data tied to locations on Earth. GIS tools can answer spatial questions: What is near this location? Which areas overlap? How far is it between these points?
GIS is used in urban planning, emergency management, environmental monitoring, public health, transportation, and many other fields. Common GIS software includes QGIS (free) and Esri ArcGIS (commercial).