A representation of a real-world spatial phenomenon which can be modelled by a geometry and zero or more scalar-valued properties.

Feature collection

A set of features from a spatial dataset. In pg_featureserv, these are mapped to database tables and views.

Spatial database

A database that includes a “geometry” column type. The PostGIS extension to PostgreSQL adds a geometry column type, as well as hundreds of functions to operate on that type. For example, it provides the ST_AsGeoJSON() function that pg_featureserv uses.


An Application Program Interface (API) allows client software to make programmatic requests to a service and retrieve information from it.

A Web API is an API founded on Web technologies. These include:

  • Use of the HTTP protocol to provide high-level semantics for operations, as well as efficient mechanisms for querying, security and transporting data to clients
  • Following the REST paradigm to simplify the model of interacting with data
  • Using the standard JSON and GeoJSON formats as the primary way of encoding data