What is Layer "Layer" in Adobe Illustrator CC 2015?

Question

Adobe Illustrator

What is Layer "Layer" in Adobe Illustrator CC 2015 is an additional organization element? Or is it more functional?

Answer 1

In the next question, I wrote, in principle, it fits here :)
In Illustrator, each object is in its own layer, so the layers that are visible in the Layers panel (Layer 1 on the screen) are essentially groups of layers. They can be combined into groups of layers of a higher order, and so on ad infinitum.