The following is a simple example of how layers work in in the GIS Viewer. The idea here is to show you a simple example so you will undersand how the layer parmeters are used. Then you can look at at the set of layer parameters and make some sense of them.
Simple layers are things like a raster image or a dot.
Composite layers are layers that are made up of sub layers, usually a list or array of layers. In the example below there is the base layer a single raster layer. Each layer parameter is a name value pair and the value part of the layer has a pretty consistent format. The name part actually has a consistent format as well. I'll explain the naming convention under the Base Layer section.