Since time immemorial, it has been a constant endeavor of human being to pursue various aspects of life with ease. In the present era of high-end computing, this endeavor of simplifying things is well achieved by an effective tool like Geographical Information System (GIS). Unlike the conventional procedure of simultaneous handling of various maps such as village cloth maps, engineering drawings and Layout plans etc., which are of different scale, GIS helps to prepare the maps and peruse the maps of multiple types at the same instance. The concept of layer mechanism and subsequent superimposition one above the other is used so as to store both non-spatial and spatial data in different thematic layers. This enhances data accessibility, and also helps simultaneous operation of perusal and analytical assessment of the information to be used prior to any land acquisition process.
GIS is a computer-based software that links geographic information (where things are) with descriptive information (what things are). Five basic components of a GIS include the computer system (hardware and operating system), the software, spatial and attribute data management, analysis procedures, and the people to operate the GIS. A GIS must always exhibits six functionalities that include Data Capture, Storage, Management, Retrieval, Analysis and Display (Clarke, 2001).
All GIS software has been designed to handle spatial data (also referred to as geographical or navigational data). Spatial data are characterized by information about position, connections with other features and details of non-spatial characteristics (Burrough, 1986). Inappropriate referencing system may restrict future use of the GIS (Openshaw, 1990). GIS supports both raster and vector data models for the representation of real-world features (Dale and McLaughlin, 1988 and Peuquet, 1990).