GIS
Geographic information system (GIS) software is a discipline unto itself. Your local environmental engineer, town planning department, regional land use planning agency, or conservation commission may use one system in particular, but there are many. The ArcGIS system by ESRI is one of the most widely used. And actually, everyone uses GIS systems whether they realize it or not. If you've ever used Google Maps, or navigation system in your car, then you're actually using a GIS system. This article summarizes some of the solutions for intentional use of GIS systems for leisure activities like hiking, biking, motorcycling, or creation activities such as land use planning or just contributing to existing datasets.
ArcGIS
ArcGIS is proprietary software. Although available for personal use in a limited fashion, it is prohibitively expensive to do more advanced work. Annoyingly, like all commercial software, they stand on the backs of all the community-driven volunteer work of Open Street Maps. Here is a vector map of Salisbury, MA from ArcGIS based on OSM.
QGIS
QGIS (formerly Quantum GIS - see wp:QGIS) is a spatial visualization and decision-making tool that is completely free software. Being completely free and open doesn't solve everything. Because it is powerful and complex software, it certainly requires some training and effort to use. This 4+ hour tutorial is for beginners.
Using
See the article on Using OpenStreetMaps to design a Disc Golf Course
References