what this means : var questionNumber = $(this).parents().eq(2).index(); ?

Hi,
I am new to jquery, can you please explain to me what this line means :
var questionNumber = $(this).parents().eq(2).index(); ?
Thanks

 

Looks to be a complicated way of returning the index of the given matching element.
The code assigns a variable (var) named questionNumber - this variable looks for the containing object's ($(this)) parents, finds number 3 (.eq(2) <- zero-based indexing) and returns that items index() - I'm a little unsure as to what this is supposed to do.
Have a look here:
https://api.jquery.com/eq/ regarding .eq()
and here:
http://api.jquery.com/index/
regarding .index()

 

Thanks lot,