What is a layer?
Put simply, a layer is just an invisible drawer to store things. Using groups alone is like piling objects together to clean up a room. Sure, it makes the room appear cleaner, but after a while, the groups just become another mess. Wouldn’t it be nice if we could put our neat piles of objects in drawers?
This would then enable us to close the drawers and hide those objects until we need them. This is precisely how we use layers in projects. A layer can be seen as a metaphorical drawer, and closing said drawer is equivalent to hiding the layer.
