Geographical Information Systems are widely used tools for analyzing,
processing and visualizing of geo-data. The new medium of the World Wide Web
(WWW) provides a big platform to publish GIS maps to a large number of users. This
new application characteristic can be called web GIS.
Since the amount of spatio-temporal data stored in databases and GIS
increased enormously, web GIS applications become a promising tool to display these
data to a broad audience. How these datasets are displayed technically depends on the
applied visualization method.
One of the most important powers of GIS is the capability to publish and share
geo-spatial information on the Internet among large numbers of people. Sharing of geospatial
information is an important and effective way of working in many kinds of
applications. Geo-spatial information includes not only maps or locations of
landmarks/facilities, but multiple attribute data, socio-economic data, ground photos,
aerial photographs, satellite images, etc., which may have static or dynamic
characteristics. By sharing this information on the Internet, accessibility, time response,
and understandability are drastically improved compared to conventional paper
distribution of maps or character based Web systems. Users will have more freedom to
choose information or layers to see and synthesize maps that will fit their own
requirements
