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GIF (image file format):

Graphical Interchange Format, GIF, is a bitmap image compression format, which was developed by CompuServe to show images over the Internet. GIF uses indexed colour, which is limited to a palette of 256 colours (


A Geographic Information System (GIS) is a system for creating and managing spatial data and associated attributes. In the strictest sense, it is a computer system capable of integrating, storing, editing, analyzing, and displaying geographically-referenced information. In a more generic sense, GIS is a "smart map" tool that allows users to create interactive queries (user created searches), analyze the spatial information, and edit data (


The Geography Markup Language (GML) is the XML grammar defined by the Open Geospatial Consortium (OGC) to express geographical features. GML serves as a modeling language for geographic systems as well as an open interchange format for geographic transactions on the Internet. (


The GPS or Global Positioning System is a system for navigation and position that uses satellite information that relays coordinates to a hand held device used in the field. Apart from position and elevation, distances moved and speed can be determined between two points ().

Graphic files:

A file that contains only graphic images such as line drawings, scanned images, photographs or type designs within a graphics file format. Though it may contain type, the type in a graphics file is often presented as pictures and cannot be edited with text editing programmes. (


In computing, HyperText Markup Language (HTML) is a markup language designed for the creation of web pages and other information viewable in a web browser. HTML is used to structure information, denoting certain text as headings, paragraphs, lists and so on, and can be used to describe, to some degree, the appearance and semantics of a document.



A hyperlink is a direct link that sends a users' web browser from one web page to another at the same or different websites. Often inserted as a highlighted address or word or 'click here' sign within a web page or text document.