GIS is abbreviation from Geographical Information System
A GIS system is designed to model information, processes and structures that mirror the world as it exists, including its history, in order to understand, analyze and manage resources and facilities.
A GIS and can be described like a corporate database management system which generally presents the data interactively to users in a seamless, graphical view that can easily be queried and analyzed.
Generally, the data from a GIS system, may be divided into background and foreground data corresponding to a map base respectively objects in real world that need to be represented in the system.
To start working in a GIS system you must have an adequate database (some form of map base completely covering the area of the GIS) which is obtained after a data capture process.
Largest costs for any organization embarking on the implementation of a GIS are data conversion, hardware and software and system implementation particularity customization but these costs are covered in time by the efficiency of work and the ability to take decisions in real time.