GeoJSON

•  GeoJSON is a format for encoding a variety of geographic data structures.

 http://geojson.org/

Geography Markup Language (GML)

• Geography Markup Language (GML)

 The OpenGIS® Geography Markup Language Encoding Standard (GML) The Geography Markup Language (GML) is an XML grammar for expressing geographical features. GML serves as a modeling language for geographic systems as well as an open interchange format for geographic transactions on the Internet
 http://www.opengeospatial.org/standards/gml

•  OGC Web Services Context Document defines the application state of an OGC Integrated Client

 http://en.wikipedia.org/wiki/Open_Geospatial_Consortium

•  The ISO 19100 is a series of standards for defining, describing, and managing geographic information

 http://www.slideshare.net/Databaseguys/iso-19100-geographic-information-and-geomatics
 

PostGIS

•  PostGIS

 PostGIS is a spatial database extender for PostgreSQL object-relational database. It adds support for geographic objects allowing location queries to be run in SQL.
 http://postgis.net/