In the beginning of the 19th century we had the industrial revolution, in the middle of the 20 th century we have the digital revolution, and in the dawn of the 21st century we have the communication revolution. The major innovation which upturned the communication revolution is the artificial satellite. Generally satellites use the latest technology for communication, remote sensing, weather forecasting and the like.

Global positioning system, usually called GPS are used to communicate with satellites and with receivers in the different parts of the world. This seminar aims to throw light into the technical details, advantages, pitfalls and major application areas of the GPS systems.

Many of our decisions depend on the details of our immediate surroundings, and require information about specific places on the earth surface. In this regard, recent studies in information technologies have opened a vast potential in communication, analysis of spatial and temporary data. Data representing the real world can be stored and processed so that they can be represented later in a simplified form to suite specific needs. Such information is called geographical because it helps us to distinguish one place from another and to make decisions for one place that are appropriate for that location. Geographical information allows us to apply general principles to specific condition of each location, allows us to track what is happening at any place, and helps us to understand how one place differs from another. Spatial information is essential for effective planning and decision making at regional, national and global levels.

Geographical information in the form of maps , photos taken from aircrafts and images collected from space borne platforms can be represented I digital form, this opens an enormous range of possibilities for communications ,analysis modeling, on accurate decision making but a degree of approximation .

GIS can be defined as computerized information storage processing and retrieval system that has hardware software specially designed to cope with geographically referenced spatial data.