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Overview of GIS
Some Interesting Links :
- What is GIS ?
Geographical Information Systems Definition by GIS.Com
- A revised Definition of GIS
For the purpose of Exploring Geographical Information Systems
- Definitions of GIS
Compiled by Kenneth E. Foote and Margaret Lynch, The Geographer's Craft Project, Department of Geography, University of Texas at Austin.
- Definition Of GIS: The Manager's Perspective
Paper presented at the International Workshop on Dynamic and Multi-Dimensional GIS held at Hong Kong, 25-26th August 1997
- GIS : Definition
Definition of GIS by the Northwest GIS Services Inc.
Answers GIS can give
Till now GIS has been described in two ways:
- Through formal definitions, and
- Through technology's ability to carry out spatial operations, linking data sets together.
However there is another way to describe GIS by listing the type of questions the technology can (or should be able to) answer. Location, Condition, Trends, patterns, Modelling, Aspatial questions, Spatial questions. There are five type of questions that a sophisticated GIS can answer:
Location What is at
.?
The first of these questions seeks to find out what exists at a particular location. A location can be described in many ways, using, for example place name, post code, or geographic reference such as longitude/latitude or x/y.
Condition Where is it
.?
The second question is the converse of the first and requires spatial data to answer. Instead of identifying what exists at a given location, one may wish to find location(s) where certain conditions are satisfied (e.g., an unforested section of at-least 2000 square meters in size, within 100 meters of road, and with soils suitable for supporting buildings)
Trends What has changed since
..?
The third question might involve both the first two and seeks to find the differences (e.g. in land use or elevation) over time.
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