GeoServer connects your information to the Geospatial Web. With GeoServer, you can publish and edit data using open standards. Your information is made available in a large variety of formats as maps/images or actual geospatial data. GeoServer's transactional capabilities offer robust support for shared editing. It supports WFS-T and WMS open protocols from the OGC to produce JPEG, PNG, SVG, KML/KMZ, GML, PDF, Shapefiles, GeoRSS, JSON, and more. It is built on the GeoTools2 Java GIS toolkit.
This version contains a vast number of bugfixes. Since 1.5, performance for rendering maps has improved drastically. The WFS 1.1 specification is now fully supported, as GeoServer is the reference implementation. There is also versioning support, to allow wiki-style maps with diff, history, and rollbacks in editing. Google Earth and Maps support is much improved, as are the Oracle and ArcSDE backends.