What is GIS ?

GIS is a computerized technology that uses a geographic information system as an  framework for managing and integrating data. Full form of GIS is Geographic Information System.

A method to visualize, manipulate, analyze, and display spatial data , also linking a database to the maps in GIS

GIS is a System of computer software, hardware and data, and personnel to manipulate, analyze and provide information that is tied to a spatial location –

• spatial location– usually geographic location
• Information– visualization of analysis of data
• System– linking software, hardware, data

GIS is often associated with maps. A map, represents geographic data in a GIS.

In GIS there is 2 ways to Input and Visualize Data

• Raster – Grid

bullet pixels
bullet a location and value
bullet Satellite images and aerial photos are already in this format

• Vector – Linear

bullet Points, lines & polygons
bullet “Features” (house, lake, etc.)
bullet Attributes
bullet size, type, length, etc.

Data required for GIS Applications
bullet Digitized and Scanned Maps
– purchased, donated, free (Internet)
– created by user
bullet Data Bases – Tables of data
bullet GPS – Global Positioning System for accurate locations
bullet Remote Sensing

Where GIS is used ?
bullet Emergency Services – Fire & Police
bullet Environmental – Monitoring & Modeling
bullet Business – Site Location, Delivery Systems
bullet Industry – Transportation, Communication,
Mining, Pipelines, Healthcare
bullet Government – Local, State, Federal, Military
bullet Education – Research, Teaching Tool,

Administration wherever Spatial Data Analysis
is Needed