Foreground and Background Layers
By default, objects you add to a patcher are in the foreground layer. Objects in the background layer appear behind all objects in the foreground layer. In addition, the background layer can be locked, so you can reposition objects in the foreground layer on top of the background without it getting in the way.
The two layers exist in both patching and presentation modes. However, the layer an object belongs to is the same in both modes.
Moving an object to the background layer

Moving an object to the background layer

Locking and unlocking the background layer

Hiding layers

Note that the invisibility of the background or foreground layers is only a temporary setting for editing purposes. Both layers will always be visible when you open a patcher. Hiding the foreground is useful for making changes to objects in the background without the foreground objects getting in the way.