What is the WMS

A Web Map Service (WMS) is a standard protocol for serving georeferenced map images over the Internet that are generated by a map server using data from a GIS database.

Ok, that's the definition from Wikipedia, not exactly very useful is it ? In human language, WMS is a way to exchange maps. The cool thing with maps is that though they usually look like simple images, they're in fact a little more complicated. On a simple image, the two axes X and Y start at 0. That means that if you superimpose two images, their 0 will overlap and that's it. You will have to manually adjust them. Maps are different:

Georeferencement

Maps use a coordinate system a little more complicated which allow them to be in the right place when you superimpose them. For example, if you superimpose a map of Australia over a map of the World, you'll most likely want Australia to be at the right place, well that's exactly what WMS does. A WMS Server send an image of the map and its coordinates.

Why should we care ?

WMS on MapsGeek works both ways. You can import WMS maps from external servers in your own maps, usually saving you a lot of work mostly because the map is already done. And you can 'export' maps via WMS. That means you can access MapsGeek maps from other sites and superimpose your MapsGeek maps with others. Here is a website that has a catalog of WMS Server, including MapsGeek: http://wms-sites.com/.

MapsGeek WMS Server address is : http://www.mapsgeek.com/wms/