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QGIS, formerly Quantum GIS, is a user friendly open source Geographic Information System (GIS) licensed under the GNU General Public License that runs on Linux, Unix, Mac OSX, and Windows and supports numerous vector, raster, and database formats and functionalities.

GRASS GIS (Geographic Resources Analysis Support System) is an open source, free software (FOSS) Geographical Information System (GIS) with raster, topological, vector, image processing, and visualization functionality. Used for geospatial data management and analysis, image processing, graphics/maps production, spatial modeling, and visualization, GRASS is currently used in academic and commercial settings around the world, as well as by many governmental agencies and environmental consulting companies. »

PostGIS adds support for geographic objects to the PostgreSQL object-relational database. In effect, PostGIS "spatially enables" the PostgreSQL server, allowing it to be used as a backend spatial database for geographic information systems (GIS), much like ESRIs SDE or Oracles Spatial extension. PostGIS follows the OpenGIS "Simple Features Specification for SQL" and has been certified as compliant with the "Types and Functions" profile.

ArcGIS is geographic information system (GIS) software for visualizing, managing, creating, and analyzing geographic data. Using ArcGIS, you can understand the geographic context of your data, allowing you to see relationships and identify patterns in new ways.

gvSIG is a Geographic Information System (GIS), that is, a desktop application designed for capturing, storing, handling, analyzing and deploying any kind of referenced geographic information in order to solve complex management and planning problems.

SAGA - System for Automated Geoscientific Analyses - is a Geographic Information System (GIS) software with immense capabilities for geodata processing and analysis. SAGA is programmed in the object oriented C++ language and supports the implementation of new functions with a very effective Application Programming Interface (API). Functions are organised as modules in framework independent Module Libraries and can be accessed via SAGA’s Graphical User Interface (GUI) or various scripting environments (shell scripts, Python, R, ...). »

The GEOCONCEPT solution was designed first and foremost to respond to expectations of users who wanted to leverage the power of geographical data to the fullest.

Mapline is the simplest mapping software on the planet! Be empowered with map visualizations from Excel spreadsheet data to optimize logistics, enhance market planning, identify growth opportunities, or mitigate market risks. Create your first map now!

uDig is a GIS software program produced by a community led by Canadian-based consulting company Refractions Research. It is based on the Eclipse platform and features full layered open source GIS. It is written in Java and released under GNU Lesser General Public License.

MapInfo Professional is a powerful, functionally rich desktop mapping application from Pitney Bowes MapInfo, designed to enable organisations to solve business problems that have a geographical element.

Beautiful, User Friendly online mapping software that scales to big data.

What3words encodes geographic coordinates into 3 dictionary words (for example, the Statue of Liberty is located at planet.inches.most). what3words is different from other alphanumeric location systems and GPS coordinates in that it displays 3 words rather than long strings of numbers or letters. what3words has a website, apps for iOS and Android, as well as an API that enables bidirectional conversion of what3words address and latitude/longitude coordinates.Source: Wikipedia

Business mapping software (geographic information system) that delivers affordable, easy-to-use, professional mapping tools for mapping in these sectors: franchising, health care, business, territories, site selection, sales, marketing, banking, more

MapET Spatial Feature Server is software that makes your geographic information (vector data) available to others in your organization and optionally anyone with an Internet connection. This is accomplished through web services, which allow a powerful server computer to receive and process requests for information sent by other devices. MapET Spatial Feature Server opens your GIS to devices that can connect to web services.