The Web Map Service (WMS) is defined by the Open Geospatial Consortium (OGC) in order to produce maps using geographic information dynamically. This standard defines a map as a representation of the geographic information using a digital raster file. WMS maps are usually generated as a raster file (PNG or JPEG), and they can be invoked by any web protocol or prepared software which is able to support this kind of services.

This standard defines three basic actions:
  1. GetCapabilities, it returns metadata of the service.
  2. GetMap, it returns a map using an image.
  3. GetFeatureInfo, it returns the information of the geographic features coming from the cartographic coverages of the map.

The URLs of the WMS are the following:

The previous urls allow users to download an XML file with the service specifications such as reference system, monitoring available cartographic coverage at scale to name but a two. The integration of the mentioned WMS can be carried out from web environments as well as other public entity viewers, Google Maps and SIG clients. Below, more detailed examples of these WMS: