A GIS includes capabilities for digital data creation, the storage and retrieval of digital data, the manipulation and analysis of those data, and the presentation of data using maps, graphs, tables, and other displays.
Digital data creation involves ways of taking the world that we see around us and representing it in a machine-readable form. Global Positioning Systems (GPS) technology provides a high-tech way of collecting geographic data. A hand-held GPS unit in the field receives signals from satellites to determine the latitude, the longitude, and the elevation to within less than one meter of a person's location on the Earth's surface. This technology can be used to build GIS databases for mapping features such as roads, property lines, buildings, wetlands, trees, manhole covers, and a variety of other features.
Once data are collected, it is stored in a computer database. Users can then retrieve selective geospatial information from the database by making queries. A water department, for example, interested in preventative maintenance might ask the GIS to identify locations of PVC water pipes that are six inches in diameter and were last maintained prior to 2014. The capability to query the GIS database and display the results on a map is a rather simple, yet powerful tool.