What is the purpose of the "active" toggle on fcurve modifiers? What is the purpose of this toggle?



What can it be used for?
The manual page doesn't mention anything about it as far as I can see.
For example, if I click on the noise modifier and it put my mouse over it, it says "F-curve modifier is the one being edited":


and if I click on the noise modifier and it put my mouse over it, it says "F-curve modifier is the one being edited":


The graph displayed looks the same whether one or the other is selected.

It basically says which modifier you clicked on

Maybe this could help:
http://www.blender.org/api/blender_python_api_2_75_3/bpy.types.FModifier.html