Layer Visibility and Locking Layers
Maya 2012 Tutorial
How to Lock and Set Layer Visibility in Maya
Once you have your objects organized in layers, you can turn the visibility on an off for all the objects on the layer by clicking the Visibility icon. You can also lock all the objects on a layer to prevent them from being moved.
Open a scene with a pyramid and a sphere. Each object should be on it's own layer. For more information, see topic, Adding Objects to Layers.
Click the left box on the sphere layer. The "V" disappears along with the object. This is the visibility icon.
Click the box again and the object reappears.
If you click the second layer box, it has three options, empty, T or R.
The empty setting means Normal, T indicates a Template layer. Template layer objects display as ghosted. Objects on a template layer are visible in the workspace but do not appear when your scene is rendered.
The R setting means Reference. It locks the layer contents once all the layer objects are deselected.
The final layer option box is used to access the Edit Layer dialog box.