Differential Global Positioning System (DGPS) is an enhancement to Global Positioning System that provides improved location accuracy, from the 15-meter nominal GPS accuracy to about 10 cm in case of the best implementations. DGPS uses a network of fixed, ground-based reference stations to broadcast the difference between the positions indicated by the satellite systems and the known fixed positions. These stations broadcast the difference between the measured satellite pseudoranges and actual (internally computed) pseudoranges, and receiver stations may correct their pseudoranges by the same amount. The digital correction signal is typically broadcast locally over ground-based transmitters of shorter range.

They are called WebGIS the geographic information systems (GIS) published on the web . A WebGIS is thus an extension of the web application born and developed to handle the mapping numbers. A WebGIS project is distinguished by a GIS project for the specific purposes of communication and information sharing with other users. With WebGIS applications developed for utilities GIS traditionally stand-alone or in environments LAN can be deployed on web servers (also called map-server ) allowing interaction via internet with cartography and data associated with it. The best known examples of WebGIS are web applications for mapping the location, the street maps or atlases online. WebGIS applications are used by the browser Internet, sometimes with the use of specific plugins , or by means of distinct software such as Google Earth . Other typical examples of GIS applications published version of WebGIS are geographic information systems (GIS) of the regions and of different municipalities: these make accessible information to citizens on environmental, urban, territorial offend a map-based navigation of the same.

Software development (also known as application development, software design, designing software, software application development, enterprise application development, or platform development)[1] is the development of a software product. The term "software development" may be used to refer to the activity of computer programming, which is the process of writing and maintaining the source code, but in a broader sense of the term it includes all that is involved between the conception of the desired software through to the final manifestation of the software, ideally in a planned and structured process.[2] Therefore, software development may include research, new development, prototyping, modification, reuse, re-engineering, maintenance, or any other activities that result in software products.

In imaging science, image processing is any form of signal processing for which the input is an image, such as a photograph or video frame; the output of image processing may be either an image or a set of characteristics or parameters related to the image. Most image-processing techniques involve treating the image as a two-dimensional signal and applying standard signal-processing techniques to it. Image processing usually refers to digital image processing, but optical and analog image processing also are possible. This article is about general techniques that apply to all of them. The acquisition of images (producing the input image in the first place) is referred to as imaging.