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GIS is commonly defined as:
"An organized collection of computer
hardware, software, geographic data, and personnel designed to
efficiently capture, store, update, manipulate, analyze, and display all
forms of geographically referenced information" (ESRI,1994).
OR
"A powerful set of tools for collecting,
storing, retrieving at will, transforming, and displaying spatial data
from the real world for a particular set of purposes."
In the past years geographic information
systems have become rapidly more popular. The application of geographic
information systems has found its way into:
The collection of data about the
spatial distribution of properties of the earth's surface has been an
important part of activities of organized societies. The findings were
rendered in pictorial form by the map maker or cartographer. Maps were
used to described far-off places as an aid in navigation and/or military
strategists. In Roman times, the land surveyor was an important part of
the government, and the fruits of their work can still be detected in
the landscapes forms of today's Europe. With the decline of the Roman
empire, surveying and map making declined. It was not until the 18th
century when European society reach that state of organization, such
that many governments realized the value of systematic mapping of their
lands.
As the Europeans spread their
influence on the globe, they introduced their ideas and methods of
mapmaking to other countries. As the scientific study of the earth
advanced, so new material needed to be mapped. The rapid development of
sciences led to an increased knowledge and understand of our natural
resources (soils, geology, ecology, land use). These sciences provided
new materials to be mapped. These maps were rather thematic than
general, because they contain information about a single subject or
theme.
It was not until the early1960's
and 1970's before computerized data collection and map making were
established. The combination of maps and associated describing data led
to the technology we now call geographic information systems (GIS). In a
geographic information system data are stored as separate layers, with
each layer representing one theme. But geographic information systems
are more then a collection of maps and data. |
