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 will be submitted for conformance testing at version 1.0.

Highlights include:

Geometry building functions, including line merging, polygon creation and vertex manipulation,
Linear referencing functions, including support for measures,
Performance improvements to coordinate reference transformations,
Autoconfiguration support, removing the old installation requirement for a built PostgreSQL source tree (for PostgreSQL 8.0 and up),
JDBC2 support in Java classes, and
A renewed and improved regression testing suite.