|
|
|||||||||||||||||||||
|
|
A Geographic Information System (GIS) can be defined as a computer system capable of assembling, storing, manipulating, and displaying geographically referenced information, e.g. data identified according to their locations. Using GIS we can record, store, analyse, and display spatial features that exist, and events that happen; on, above, or below the earth. GIS can generate two- or three-dimensional images of an area, showing natural features such as hills and rivers with artificial features such as roads and power lines. Scientists use GIS images as models, making measurements, gathering data, and testing ideas. It can also convert existing digital information, which may not yet be in map form, into forms it can recognise and use. For example, aerial photographs and digital satellite images can be analysed to produce a map like layer of digital information about vegetative covers. Many GIS databases consist of sets of features called layers. Each layer represents a particular type of geographic data. The GIS combines these layers into one image, showing how various types of data relate to one another. Geographic data from a variety of sources, including paper and digital maps, Global Positioning Systems (GPS), satellite imagery, aerial photography, and printed text and statistics can be used within GIS. Operators program the GIS to process the information and to produce the images or information they need. Explore the pages on this site and try using GIS for yourself
|
||||||||||||||||||||
