Every layer has a name. Typically, the name of the layer is the page number, but it can be labeled  as you want.

Every layer has a type.

Every page has own set of layers and it may have different number of layers. For details, see How many layers do you need?

Layers on a specific page can be stacked at will and made visible or hidden independently of other layers.

Layer may have own set of column guides. See Layer grid properties.

Layers can be locked and protected against unauthorized access. The advertisement layer can be locked so that the editorial staff cannot make modifications and vice-versa.

 

Use the Table of Contents to find information. See also Using table of contents in help.