Geographical Information Systems (GIS) is a computer-based technology for capturing, retrieving, processing and updating spatial information (i.e. location- specific information).

The power of GIS lies in its ability to deal with and analyze various types of data across multiple layers of digital information. GIS applications extend across a number of fields which include among other things the following: Geography, environmental and natural resource management, utilities and facilities management, city planning, transportation, and demography, in addition to its role in cartography and map production.

Remote sensing is the science concerned with studying the Earth resources, through computer-assisted interpretation of spatial data, collected at a distance above the Earth. The measurements are made by instruments carried by satellites or aircrafts, and are used to infer the nature and characteristics of the land or sea surface at the time of observation.

The power of remote sensing is attributed to several factors, mainly the following: firstly, its wide coverage and synoptic; secondly, it has a multi-spectral capability which enables the user to extract information that is otherwise hidden from the naked eye, and thirdly, its multi-temporal capability (i.e. frequent re-visiting of the same area) which is necessary for monitoring and change detection purposes. The following are the major fields where remote sensing techniques have been used effectively:

• Geology and hydrology.
• Environmental management.
• Agricultural application.
• Land-use and city planning.
• Meteorology and disaster forecasting and monitoring.
• Infrastructure Management.

High-resolution satellite data for the Gulf region is now available on regular basis from different sources. One important source of raw data for the Gulf region is the remote sensing receiving station located in King Abdul Aziz Science and Technology in Riyadh (Saudi Arabia).

Global positioning systems (GPS) are based on a system of 24 orbiting satellites deployed by the U.S. Department of National Defense. The system allows for precise positioning 24 hours a day, and gives sub-meter accuracy when differential correction is used.

GPS technology has had a profound positive impact on ground, sea, and air navigation, as well as on surveying and mapping. For instance, surveys which once took months of intensive work now take only days to complete. GPS has affected the remote sensing and GIS industry by providing an accurate, reliable and easy to use means of data collection and ground truthing.