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What is GIS?

GIS is an acronym for geographic information system.

Loosely defined, GIS could be explained as “computerized mapping.”

In a more technical sense, GIS is “an integrated collection of software and data used to view and manage information about geographic places, analyze geographic relationships, and model geographic processes. A GIS provides a framework for gathering and organizing geographic data and related information so that it can be displayed and analyzed. (ESRI)

The Fundamentals of GIS

GIS is more than making maps. It links information to location and provides a powerful tool to visualize the relationship between layers of geographic information. What is a layer? A layer is each piece of information represented on a map. On the map below, for example, roads, buildings, and water are different layers. The ability to “stack” or display layers on top of each other is one of the fundamental concepts of GIS. GIS can be used to answer geographic-based questions such as “how many features are located within?” “How close is one feature to another?” “What is the closest feature to my location?” and “What is the quickest way to get from point ‘A’ to point ‘B’?”

Interactive Layer Example

Below is an interactive map example that helps illustrate the concept of GIS layers.

Suppose you have a house in Midland that you wish to purchase but are not sure about the details of the location. You can use GIS to turn on layers to show the roads, buildings and the rivers in the area you wish to purchase your home. These layers can be turned on by clicking on the checkboxes () in the legend below.

When attempting to finance this home, your lending institution informs you that you will need to purchase flood insurance if your house is in the flood plain. You can use GIS to determine if the property you are considering is in the flood plain by turning on that layer. Click here to view the flood plain: .

If you have children, you will be interested in the schools and parks that are near the property you wish to purchase. You can use GIS to view the closest schools and parks in the area of your new house by turning on those layers. Click here to view the parks and the schools layers.