Free and Open Source Geospatial Software

This is in no way intended to be a complete list of open source GIS software. I attempted to focus on those software suits that had the most promise for use in historic preservation site documentation and which were also relatively easy to learn. If you feel that there are other tools which should be listed here, please contact me.

Geographic Resources Analysis Support System (GRASS)
GRASS is a Free Software Geographical Information System (GIS) with raster, topological vector, image processing, volume voxel management/visualization, 2D/3D vector engine with vector network analysis and graphics production functionality that operates on various platforms through shell and a graphical user interface.
Books:
Open Source GIS: A GRASS GIS Approach. Third Edition.
ISBN-13: 978-0-387-35767-6
Links:
http://grass.osgeo.org/
http://grass.itc.it/
http://grass.itc.it/

MapServer
The heart of UMN MapServer is a CGI-based application for delivering dynamic GIS and image processing content via the World-Wide Web (WWW). The package also contains a number of stand alone applications for building maps, scalebars and legends offline. Access to the development environment of MapServer is possible with a number of different programming languages.
Links:
http://www.mapserver.org/
Installs MapServer on a Linux system:
FGS Linux Installer

MapWindows
The MapWindow GIS project includes a free and open source desktop geographic information system (GIS) with an extensible plugin architecture; a GIS ActiveX control; and C# GIS programmer library called DotSpatial. We would be happy to have you join our project. Feel free to browse this site, or follow the links below depending on if you are a GIS user, GIS programmer, or potential project contributor.
http://www.mapwindow.org/

POSTGIS
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 ESRI’s SDE or Oracle’s Spatial extension. PostGIS follows the OpenGIS “Simple Features Specification for SQL” and has been certified as compliant with the “Types and Functions” profile.  PostGIS has been developed by Refractions Research as a project in open source spatial database technology. PostGIS is released under the GNU General Public License. We continue to develop PostGIS, and have added user interface tools, basic topology support, data validation, coordinate transformation, programming APIs and much more. Our list of future projects includes full topology support, raster support, networks and routing, three dimensional surfaces, curves and splines and other features. Ask us about consulting services and implementing new features.
http://postgis.refractions.net/

SAGA GIS
SAGA GIS (System for Automated Geoscientific Analyses) is a free and open source geographic information system used for editing spatial data. It was originally developed by a small team at the Department of Physical Geography, University of Göttingen, Germany, and is now being maintained and extended by an international developer community.
SAGA GIS is a GIS software with the purpose to give (geo-)scientists an effective but easily learnable platform for the implementation of geoscientific methods. This is achieved by the API. SAGA has a fast growing set of geoscientifc methods, bundled in exchangeable Module Libraries.
http://www.saga-gis.org/

Quantum GIS
Quantum GIS (QGIS) is a user friendly Open Source Geographic Information System (GIS) licensed under the GNU General Public License. QGIS is an official project of the Open Source Geospatial Foundation (OSGeo). It runs on Linux, Unix, Mac OSX, and Windows and supports numerous vector, raster, and database formats and functionalities.
http://www.qgis.org/

Specific GIS Application Tools

Geospatial Data Abstraction Library (GDAL)
GDAL is a translator library for raster geospatial data formats. As a library, it presents a single abstract data model to the calling application for all supported formats.
Links:
http://www.gdal.org

The Generic Mapping Tools (GMT)
GMT is a collection of about 60 UNIX tools that allow users to manipulate (x,y) and (x,y,z) data sets (including filtering, trend fitting, gridding, projecting, etc.) and produce Encapsulated PostScript File (EPS) illustrations ranging from simple x-y plots through contour maps to artificially illuminated surfaces and 3-D perspective views in black and white, gray tone, hachure patterns, and 24-bit color. GMT supports 30 common map projections plus linear, log and power scaling, and comes with support data such as coastlines, rivers, and political boundaries.
http://gmt.soest.hawaii.edu/

Web Mapping:

Chameleon
A highly customizable and adaptable environment for deploying and managing Web mapping applications.

Fusion
An application development framework for both MapServer and MapGuide Open Source built primarily in JavaScript.

ka-Map
An Open Source package that provides a javascript API for developing highly interactive web-mapping interfaces. It has been developed to work with MapServer, but can be easily integrated with other software packages.

MapFish
An easy-to-use and extensible web 2.0 mapping application framework based on OpenLayers.

OpenLayers
A pure JavaScript library for displaying map data in most modern web browsers, with no server-side dependencies. OpenLayers implements a JavaScript API for building rich web-based geographic applications.

Photography/Graphic Design Software:

ArcheOS
ArcheOS is the acronym of Archeological Operating System. It is a GNU/Linux live distribution built for archaeological aims. Actually a new version (4.0) based on Debian “Squeeze” is under development. This distro of Linux comes with Photogramatry tools.
http://www.archeos.eu/wiki/doku.php?id=start

Insight3D
insight3d lets you create 3D models from photographs. You give it a series of photos of a real scene (e.g., of a building), it automatically matches them and then calculates positions in space from which each photo has been taken (plus camera’s optical parameters) along with a 3D pointcloud of the scene. You can then use insight3d’s modeling tools to create textured polygonal model.
http://insight3d.sourceforge.net/

OSMBundler
Constructs 3D Geomoetry from a set of photographs. Available for Windows.
http://code.google.com/p/osm-bundler/downloads/list

OSSIM
OSSIM is a high performance software system for remote sensing, image processing , geographical information systems and photogrammetry. It is an open source software project maintained at ossim.org and has been under active development since 1996.
www.ossim.org

Site Documentation:
http://www.openpilot.org/