GIS is an industry short form for "Geographical Information System", a computerized system comprised of hardware, software, data, specialized personnel and training.
This system is used to store, retrieve, manipulate, query, analyze and report on information that describes places located on the earth’s surface.
A GIS uses geography (real world coordinates) as the common key between data sets.
It combines spatial information (describing the location and shape of a geographic feature and it’s relationship to other features) with descriptive (tabular) information about the feature.
Every feature stored answers three main questions: