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Coordinate system
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Uses 3 dimensional location on earth, referenced by point w/longitude and latitude coordinates based on angular units of measure
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Projection
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Based on x and y coordinates depend on projection being used, units of measure (meters, feet, or something else) where the map is centered
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Vector data
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Stores geographic information as points, lines, and polygons (parcels) that more closely represent the actual features
Ex: hydrants = points
streets = lines
parcels = polygons
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Raster data
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Stores geographic information in a grid of rows and columns similar to excel spread sheet
Ex: precipitation or elevation
Cells are all the same size, each cell is assigned a value that represents a small section of the Earth's surface
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Map
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Is a picture or representation of the Earth's surface, showing how things are related to each other by distance
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GPS
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Global positioning system, it is a satellite based navigation system orginally for the military
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Remote sensing
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Technology for sampling electromagnetic radiation to acquire and interpret non-continguous geospatial data from which to extract info about features, objects, and classes on Earth's land surface
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GIS
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Geographic information system. GIS is a computer system for storing, managing, and displaying both the locations and attributes of specical features (geospatial data)
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GIS Applications
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1. Map location
2. Map quantities
3. Map densities
4. Find distances
5. Map and monitor changes
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ArcGIS software includes
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ArcMAP, ArcView, ArcEditor, ArcInfo, ArcCatalog, and ArcReader
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3 views of GIS
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1. Mapview- set of intelligent maps show features and feature relationships of Earth's surface
2. Database view - geodata base (desribes the world in geographic terms)
3. Model view- set of information transformation tools to derive new geographic datasets from existing ones
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GIS operations
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1. Data acquisition
2. Attribute data management
3. Data display
4. Data exploration
5. Data analysis
6. GIS models, and modeling (binary, index, regression, and process models)
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ArcCatalog
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Is an application for managing geographic data
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Shape file
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is a green rectangle and the different patterns on the green rectangle distinguish point, line, and polygon shapefiles
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Feature class
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Is a group of points, lines, or polygons representing geographic objects of the same kind
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