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  What is GIS?  

Geographic Information Systems (GIS)

GIS is a computer application that can link together data that are related by a geographic location, such as a county boundary, street address or zip code. Since the data are related by location, they can be combined to solve a problem. Data can be associated with or related to three kinds of features: point, line, and polygon.


A GIS is not simply a computer system for making maps. A GIS is an analytical tool. Using the locational associations or relationships of different data, a GIS can present the data in a visual form to help answer such questions as:

 

GIS - What is it?

What is at...?
What exists at a particular location:
What is at 100 W. Main Street

Where is...?
Find a location where a certain condition exists:
Identify the zip code area that had the highest accident rate.
What has changed since...?

What has changed since...?
Find the difference within an area over time:
Identify wetland areas that have decreased in size over the last five years.

What patterns exist...?
Determine if data fit a particular pattern based on location:
Identify the zip code area with the highest growth that is less than 5 miles from a major highway.

What if...?
What if one set of data was changed:
Based on sales data, where would be the best place to locate a new regional office?

Sample GIS Map Interface
This interface provides a sampling of a wide range of geographic data from park and university locations, taxation levels per county, senate representative areas and geological features.

Where did the state get GIS?
State agencies have been using GIs technology for years to manage and evaluate scientific data. In more recent years, local government has used GIs to manage property information. As new technology is developed, data from countless agencies and organizations can be brought together to help provide information for everyone.

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 What is GIS?
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