I have the Standard Dining Room Light Fixture that Hangs by a Chain.

I know at the Top of the Chain is what I call a Nut.
And you would Turn the Nut to make it Slid down the Chain.

Then the Faceplate would Slid down the Chain.

And from here you can get to the Wires and so on.

But am I Right is that little thing called a Nut or what is it?