
Attribute data
Data that describe the characteristics of spatial features.

Continuous features
Spatial features that exist between observations.

Coverage
An ESRI data format for topological vector data.

Data exploration
Datacentered query and analysis.

Discrete features
Spatial features that do not exist between observations, form separate entities, and are individually distinguishable.

Dynamic segmentation model
A data model that allows the use of linearly measured data on a coordinate system.

Geodatabase data model
An ESRI data model that is objectbased.

Geographic information system (GIS)
A computer system for capturing, storing, querying, analyzing, and displaying geographically referenced data.

Georelational data model
A vector data model that uses a split system to store spatial data and attribute data.

Geospatial data
Data that describe both the locations and characteristics of spatial features on the Earth's surface.

GIS modeling
The process of using GIS in building models with spatial data.

Objectbased data model
A data model that uses objects to organize spatial data and stores spatial data and attribute data in a single system.

Projection
The process of transforming from a geographic grid to a plane coordinate system.

Raster data model
A spatial data model that uses a grid and cells to represent the spatial variation of a feature.

Regions
Higherlevel vector data that can have spatially disjoint components and can overlap one another.

Relational database
A collection of tables, which can be connected to each other by attributes whose values can uniquely identify a record in a table.

Shapefile
An ESRI data format for nontopological vector data.

Spatial data
Data that describe the geometry of spatial features.

Spatial interpolation
A process of using points with known values to estimate values at other points.

Topology
A subfield of mathematics that is applied in GIS to ensure that the spatial relationships between features are expressed explicitly.

Triangulated irregular network (TIN)
A data model that approximates the terrain with a set of nonoverlapping triangles.

Vector data model
A spatial data model that uses points and their x, ycoordinates to construct spatial features of points, lines, and areas.

