You can use the Layers pane of the Map Editor to add layers to your map, create layer groups to organize layers, and control the draw order and other layer display options. Layers reside in the Site Explorer, and you add them to maps by creating a reference to them within a map. When you create a new layer reference in the Map Editor, you must specify the layer resource that you want to reference.
To control the data associated with a layer and how it is displayed in the map, use the Layer Editor. For more information, see Working with Layers.