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This is a list of GIS data sources (including some geoportals) that provide information sets that can be used in geographic information systems (GIS) and spatial databases for purposes of geospatial analysis and cartographic mapping. This list categorizes the sources of interest.
The core of any GIS is a database that contains representations of geographic phenomena, modeling their geometry (location and shape) and their properties or attributes. A GIS database may be stored in a variety of forms, such as a collection of separate data files or a single spatially-enabled relational database. Collecting and managing these ...
The georelational data model was the basis for most early vector GIS software. [19] The geometric data and the attribute data are stored separately; this was originally because the geometric data required GIS-specific code to process it, but existing relational database software (RDBMS) could be
QGIS is a geographic information system (GIS) software that is free and open-source. [2] QGIS supports Windows, macOS, and Linux. [3] It supports viewing, editing, printing, and analysis of geospatial data in a range of data formats. QGIS was previously also known as Quantum GIS.
The origin of the geodatabase was in the mid-1990s during the emergence of the first spatial databases.One early approach to integrating relational databases and GIS was the use of server middleware, a third-party program that stores the spatial data in database tables in a custom format, and translates it dynamically into a logical model that can be understood by the client software.
The World Wide Web is an information system that uses the internet to host, share, and distribute documents, images, and other data. [33] Web GIS involves using the World Wide Web to facilitate GIS tasks traditionally done on a desktop computer, as well as enabling the sharing of maps and spatial data. [7]
The scale of the Web can sometimes make finding quality and reliable data a challenge for GIS professionals and end users, with a significant amount of low-quality, poorly organized, or poorly sourced material available for public consumption. [13] [14] This can make finding spatial data a time consuming activity for GIS users. [13]
Shapefiles : are a data exchange format created by ESRI and one of the most widely used GIS/geodata formats. One "shapefile" usually include four different files : .shp, .shx, .dbf, .prj.