Adding WMS layer
Web Map Service (WMS),is a standard developed by the Open Geospatial Consortium (OGC) implemented by many geospatial servers, among which we can find the free and open source projects GeoServer (http://geoserver.org) and MapServer (http://mapserver.org). More information on WMS can be found at http://en.wikipedia.org/wiki/Web_Map_Service.
As a very basic summary, you can understand a WMS server as a normal HTTP web server that accepts request with some GIS-related parameters (such as projection, bounding box, and so on) and returns a map similar to the following screenshot:
Note
We are going to work with remote WMS servers, so it is not necessary you have one installed. As an advise, note that we are not responsible for these servers and that they may have problems, or are not available when you read this section.
Any other WMS server can be used, but the URL and layer name must be known.
How to do it...
To add a WMS layer, perform the following steps:
Create an HTML file and...
