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Tables allow data to be organised into the rows and columns of rectangular cells. This data may consist of text, images, or other tables (

Themes (Map themes):

A user-defined perspective on a geographic dataset specified, if applicable, by a name and feature or dataset name, attributes of interest, or data classification scheme (

Text files:

Computer files can be divided into two broad categories: binary and text. Text files are files that contain ordinary textual characters with essentially no formatting; binary files are all other files. Or, rather, text files are a special case of binary files, since any file is fundamentally a sequence of bits, and many computer components (for example, all hard disk circuitry and most system software) make no distinction between file types. However, a large percentage of application programs can understand and use text files in some way, but few programs can typically understand and use the contents of a particular binary file. Hence the distinction can be useful to computer users (


Is a graphic associated with various software programs. It is often found in GIS programmes, and occurs in the shape of an open box (or option). Once selected, a tick will appear in that particular box. This allows for the selection of various different options available to the particular software application being used. In the case of a GIS application tick-boxes allow one to select or deselect various layers of information.


A tool in a GIS is a computer program that allows the user to perform a specific set of operations on map and attribute data. Examples of spatial analysis tools include overlay, window, proximity and network analysis, and map algebra



A toolbox is an area on in a software application, which offers the user various useful functions in the form of drop-down menus or a collection of icons.


Unix or UNIX is a computer operating system originally developed in the 1960s and 1970s by a group of AT&T Bell Labs employees. Today's Unix systems are split into various branches, developed over time by AT&T, several other commercial vendors, as well as several non-profit organizations. Unix was designed to be portable, multi-tasking and multi-user (


A Uniform Resource Locator, URL (typically pronounced as a spelled-out initialism, but syllabized by some as 'earl'), or (less formally) Web address, is a sequence of characters, conforming to a standardized format that is used for referring to resources, such as documents and images on the Internet, by their location (

Vector graphics:

Vector graphics or geometric modeling is the use of geometrical primitives such as points, lines, curves, and polygons to represent images in computer graphics. It is used by contrast to the term raster graphics, which is the representation of images as a collection of pixels (dots) (