In this recipe, you will use the MapServer and Geoserver WMS you created in the first two recipes of this chapter using the OpenLayers open source JavaScript API.
This excellent library helps developers quickly assemble web pages using mapping viewers and features. In this recipe, you will create an HTML page, add an OpenLayers map in it and a bunch of controls in that map for navigation, switch the layers, and identify features of the layers. We will also look at two WMS layers pointing to the PostGIS tables, implemented with MapServer and GeoServer.
