In addition to the benefit of reducing cost, there are many other reasons to learn about and how to use open source GIS software:

• Bolster Your GIS Skills: Many advanced techniques in GIS are covered in costly classes, tutorials, and webinars, and are mostly aimed at practitioners employing commercial software. For those with lack of access or budgetary restraints, freely available courses and resources in open source software are available.

• Give GIS a Test Drive: Perhaps, you aren’t sure if you need to use GIS software at work. Open source GIS software will give you the opportunity to learn all aspects of GIS, so you can make an informed decision.

• Customization: Although one can integrate additional functionality into commercial software through scripting languages, having access to the source code allows GIS practitioners with programming experience to customize the software in any way they can think of.

• Business Solutions: For organizations with limited budget for software licenses, open source GIS software can be implemented in order to reduce overhead costs.

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GIS applications take many forms and serve a variety of purposes in GISystems. Some software providers offer enterprise-wide fully-featured desktop solutions that rival the functionality of ArcMap and ArcInfo, while other focus on specific aspects of GISystem software architecture. Your choice of software will largely depend on how you want your knowledge of GIS to augment your career. The following are examples of popular software providers for some of the main components of a geospatial software system:

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• Desktop GIS: Quantum GIS (QGIS) is one of the most popular and fully-developed desktop applications. It’s easy-to navigate user interface makes it a breeze to import data, query databases, and create gorgeous maps. QGIS interfaces with a number of other popular open source software including PostGIS, GRASS, and MapServer.

• Geospatial Database Design: PostGIS is a spatially-enabled implementation of the PostGRE SQL database software. PostGRE SQL is a fully-featured database management software with a powerful set of advanced enterprise features. Post GIS takes this free software into the realm of GIS with the inclusion of spatial data type storage capabilities and added functionality that allows users to perform spatial queries, indexing, and much more.

• Web Mapping Solutions: MapServer is a web server-based application that functions as an interface between local, online, and remote spatial databases and web browsers, providing a highly customizable platfor for the design and implementation of web-accessible GISystems. MapServer is a CGI application that processes requests from browsers and relays them to these databases to create maps based on end user inputs. Map Server integrates ell with PostGIS as well as other data sources based on OGC and GDAL specifications.