The map layers are shown in the list in the upper portion of the dialog. Drag layers up or down. Double-click a layer to open the Layer Symbology Editor for the clicked layer
From the context menu a set of actions for the map layers are available. Most of these actions are also available from the toolbar.
Note: Setting a layer invisible in the Layer Manager does not unload the layer from the Toolbox.
Add Layer…
Adds a GIS file from a local disk or network location.
Remove Selected Layer
Removes the selected map layer. Only external layers can be removed from the Layer Manager.
Layer Symbology…
Shows the Layer Symbology Editor for the selected layer.
Move Up
Moves the selected layer up.
Move Down
Moves the selected layer down.