GIS is a simplified world, brought into a computer environment.
It could be compared with cartography, but GIS adds another dimension - data. A map may display a parcel of land in green, with a label "Park". The park is made up of two dimensional boundary lines and a label.
In a computer, the boundary data can be stored in a table or database, and the word "park" can be stored in another table, and linked to the boundary information. Now you can ask the computer a simple question, like "how many parks are there withing 10km radius of this point?". The tabulated data easily finds the answer and displays it, either in tabular form, or in map form. This is GIS.
GIS can model what-if and thematic scenarios, using date/time, distance or any other criteria. Applications include envronment, health, roads, utlities, town planning, property records, demographics and marketing. The digital map database interacts with tabulated data on each entity, so is completely relational.
(With acknowledgement to Tor Bernhardsen, Geographic Information Systems, An Introduction, publ 1999, John Wiley and Sons)
Information stored in GIS is retrieved in many ways.
Information can be scanned from old maps or plans to start the process. Then information relating to the various subjects required, can be entered as supporting data.
At
Johnny Appleseed GPS, we have expertise to supply and support the field methods for obtaining and verifying data.
Programs are available for computer and hand-held devices, to capture position and other information in a systematic format. This information is formatted in the same manner as the parent GIS, for which the data is intended.
We supply field compatible hardware (camera, PDA, GPS, DGPS) and software to capture data.