What is OGC WMS?
WMS (Web Mapping Service) servers provide georeferenced images over the internet using the OGC WMS protocol (http://www.opengeospatial.org). There are literally hundreds of services available today that provide a wide variety of information useful to geoscientists. Each service will have a catalog of one or more visible layers organized in a hierarchical view from the URL of the service. WMS servers also provide limited metadata about both the servers and the layers of information that they host.