The EPSG Coordinate Systems is a dataset of parameters for coordinate reference system and coordinate transformation description. This dataset is known as the EPSG Geodetic Parameter Dataset, published and maintained by the IOGP Geomatics Committee. This committee was formed in 2005 by the absorption into IOGP of the now-defunct European Petroleum Survey Group (EPSG).
The EPSG geodetic parameter dataset is a repository of parameters required to identify coordinates such that position is described unambiguously through a coordinate reference system (CRS) definition, and define transformations and conversions to allow coordinates to be changed from one CRS to another CRS.
The EPSG dataset uses numeric codes for the map projections. For example, map projection NAD83/UTM zone 17N is defined as code EPSG::26917.
The EPSG geodetic parameter dataset and documentation is maintained at www.epsg-registry.org.