[Novice]

I am new to AS.
I've come across this code.

My question is: what is in this case
set((("mcNavigHold.mcNavigItem" + i) + ".myName"), root.NavigOb.NavigData.NavigItem[i].name);

suppose to do? Create new property
.myName and assign it a new value?
How was it done in AS 1.0?

How abot root? Isn't that supposed to be _root?

Actionscript:

function buildNavig() {
	NavigItems = root.NavigOb.NavigData.NavigItem.length;
	i = 0;
	while (i < NavigItems) {
		duplicateMovieClip("mcNavigHold.mcNavigItem", ("mcNavigItem" + i), (16384 + i));

		set((("mcNavigHold.mcNavigItem" + i) + ".myName"), root.NavigOb.NavigData.NavigItem[i].name);