Classification of GIS

A GIS application can be classified into the following types:

1. Four dimensional GIS
2. Multimedia or hypermedia GIS
3. Web GIS and
4. Virtual Reality GIS

The above types of GIS are briefly discussed below:

1. Four dimensional GIS are designed to handle three dimensions of space and one dimension of time. The spatio-temporal representations can handle only two dimensions of space and one dimension of time. 
2. Multimedia/hypermedia GIS allow the user to access a range of georeferenced multimedia data by selecting resources from a georeferenced image map base. A map serving as the primary index to multimedia data in a multimedia geo-representation is called a hypermap. Multimedia and virtual geo-representations can be stored either in extended relational databases, object databases or in application specific data stores.
3. Web GIS: Widespread access to the internet coupled with the use of web browsers and the explosion of geographic information has made it possible to develop new forms of multimedia geo-representations on the web. Many geomatic web solutions are web-based and are rapidly overtaking desktop GIS with the future trends following the same direction.
4. Virtual Reality GIS: Virtual Reality GIS have been developed to allow the creation, manipulation and exploration of geo-referenced virtual environments. For example, use of Virtual Reality Markup Language (VRML) to experiment with different scenarios. Virtual Reality GIS can also be web-based. An example of application of Virtual Reality GIS is 3D simulation for planning in various scenarios.