QGIS - QGIS is a desktop geographic information system, or GIS.
GeoServer - The reference implementation of the Open Geospatial Consortiums WFS and WMS services, GeoServer is...
what3words - Geocoding system for the simple communication of locations with a resolution of 3 m
Mapserver - MapServer is an Open Source platform for publishing spatial data and interactive mapping...
GRASS GIS - GRASS GIS is a free Geographic Information System (GIS) software used for geospatial data management and analysis, image processing, graphics/maps production, spatial modeling, and visualization.
ArcGIS - ArcGIS software is a data analysis, cloud-based mapping platform that allows users to customize maps and see real-time data ranging from logistics support to overall mapping analysis.