At present, Remote Sensing, GIS and GPS have become important and effective tools in diversified studies like Geosciences, Forestry and Ecology, Soil and Agriculture, Water Resources, Urban and Regional Planning etc. During early half of the twentieth century, aerial photos were used in the application of Military Surveys and Topographical Mapping. This Aerial Photography provided high spatial resolution data in three dimensions, and used for the purpose of surveying and cadastral mapping like route alignment survey or Engineering Surveys (Dam/Bridge construction) and also for urban & regional planning. However, modern remote sensing technique is providing updated and developed satellite images which are suitable for medium scale mapping to monitor, investigate, and manage the natural resources. Due to continuous research programs in space science, the remote sensing technology has become more advanced besides its various applications. » Read more: SPACE SCIENCE