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QGIS: A Free, Open-Source GIS Tool

There are many graphic information system software packages on the market. Quantum GIS (QGIS) is a free, open source option which can run on multiple operating systems and has many of the same features as "enterprise" solutions that can cost thousands of dollars. For beginner or intermediate GIS users, its features are comparable with ARCMap for making maps and for performing basic data mapping functions.

For advanced users, QGIS works with both malleable and fixed layers including shapefiles and ESRI personal geodatabase layers. One of the benefits of QGIS is that it utilizes plugins from official and 3rd party repositories, which offer a wide range of functionality. These allow for basic operations like clipping, buffering, and joining tables as well as more advanced functions like Python scripting.

Though stable on Windows, the software suffers from some reliability issues on Mac OS X. Also on Mac, installing the software is a two-step process, which can be difficult for some users. QGIS's "projections" feature is lacking: there are common projections that are not listed and new users often find it difficult to define a custom Coordinate Reference System on their own.

Despite its quirks, QGIS is a powerful GIS software package that is well suited for faculty who wish to analyze graphic information system data with students. As an example, Marcus Lam, an instructor at the School of Social Work, is using QGIS with his students. He developed a series of screencasts for his students, which we described in another EnhancED article.

(Editorial Note: Thanks to Jeremiah Trinidad, GIS/Map Librarian, and Marcus Lam for their input on this article).