OGC Standards Overview

A quick list of major OGC standards for GIS.

Official Specification: WFS
Latest Version: 1.1
Brief Introduction: The OGC Web Feature Service allows a client to retrieve geospatial data encoded in Geographic Markup Language (GML) from multiple Web Feature Services.. WFS operations support insert (INSERT), update (UPDATE), delete (DELETE), query (QUERY) and localization (DISCOVERY) of spatial feature through the HTTP protocol (web). All requests and responses are in XML format, it means that data (feature) are delivered in vectorial mode (unless feature type is bitmap of course).

Official Specification: WMS
Latest Version: 1.3
Brief Introduction: A Web Map Service (WMS) produces maps of spatially referenced data dynamically from geographic information. This International Standard defines a “map” to be a portrayal of geographic information as a digital image file suitable for display on a computer screen. A map is not the data itself. WMS-produced maps are generally rendered in a pictorial format such as PNG, GIF or JPEG, or occasionally as vector-based graphical elements in Scalable Vector Graphics (SVG) or Web Computer Graphics Metafile (WebCGM) formats.

Official Specification: SLD
Latest Version: 1.0.0
Brief Introduction: allow user-defined symbolization/portrayal of feature data based on the geometry type or a specific feature attribute. Can be used in both WMS and WFS services.

Official Specification: Filter , see also the Catalog Interface which define in more details filters.
Latest Version: 1.0
Brief Introduction: allow filtering of feature set to a user specific requirement (correspond to the WHERE clause is a SQL request).

Official Specification: GML
Latest Version: 3.0
Brief Introduction: The Geography Markup Language(TM) (GML) is an XML grammar for the encoding of geographic information including geographic features, coverages, observations, topology, geometry, coordinate reference systems, units of measure, time, and value objects.