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Actually, there are two data types only (Vector or Raster) and TIN is vector type TIN in GISDictionary
Vector: used for discrete feature with well known boundary (Building, Road ... etc.)
Raster: used for continuous features (Temperature, Elevation ... etc.)
A data model in GIS is a mathematical construct for representing geographic objects or surfaces as data. It is three types i.e. vectore data model , raster data model and tin data model
[data models] In information theory, a description of the rules by which data is defined, organized, queried, and updated within an information system (usually a database management system).
GIS data models are:
1. Spatial Data Models: Traditionally spatial data model has been stored and presented in the form of a map. three basic types of spatial data models have evolved for storing geographic data digitally. these are referred to as:
a. Raster data model: is a regular grid of cells divided into rows and columns. In a raster data set, data values for a given parameter are stored in each cell – these values may represent an elevation in meters above sea level, a land use class, a plant biomass in grams per square meter, and so forth. it is used to used digital analysis for extract information for object on the earth e.g. forest analysis
b. Vector data Model: is based upon vectors as opposed to space occupancy of raster data structures. The fundamental primitive of the vector model is a point. The various objects are created by connecting the points with straight lines, but some systems allow the points to be connected using arcs of circles
c. Image: is used to store remotely sensed imagery, e.g. satellite scenes or orthophotos, or ancillary graphics such as photographs, scanned plan documents, etc. Image data is typically used in GIS systems as background display data (if the image has been rectified and georeferenced); or as a graphic attribute.
2. Attribute Data Models:
a. Tabular Model: stores attribute data as sequential data files with fixed formats (or comma delimited for ASCII data), for the location of attribute values in a predefined record structure. This type of data model is outdated in the GIS arena.
b. Hierarchical Model: organizes data in a tree structure.Data is structured downward in a hierarchy of tables. Any level in the hierarchy can have unlimited children, but any child can have only one parent. Hierarchical DBMS have not gained any noticeable acceptance for use within GIS.
c. Network Model: organizes data in a network or plex structure. Any column in a plex structure can be linked to any other. Like a tree structure, a plex structure can be described in terms of parents and children. This model allows for children to have more than one parent.
d. Relational Model: organizes data in tables. Each table, is identified by a unique table name, and is organized by rows and columns. Each column within a table also has a unique name. Columns store the values for a specific attribute, e.g. cover group, tree height. Rows represent one record in the table. In a GIS each row is usually linked to a separate spatial feature, e.g. a forestry stand. Accordingly, each row would be comprised of several columns, each column containing a specific value for that geographic feature.
e. Object Oriented Model: To date, only a few GIS packages are promoting the use of this attribute data model. However, initial impressions indicate that this approach may hold many operational benefits with respect to geographic data processing. Fulfilment of this promise with a commercial GIS product remains to be seen.
The GIS data model represents a set of guidelines to convert the real world to the digitally and logically represented spatial objects consisting of the attributes and geometry.
There are two major GIS data models:
