This document provides an introduction to geographic information systems (GIS) and defines several key related terms. It states that GIS stands for geographic information system, with geographic information science being another name. GIS is defined as a computer information system. The company ESRI, which stands for Environmental Systems Research Institute, makes the ArcGIS Arc Editor intermediate-level GIS being used. GPS is defined as standing for global positioning system and being a navigation and positioning system, with a GPS unit being an electronic receiver of satellite signals about location. Garmin is stated to be the company that makes their GPS units.