Using createEmptyMovieClip

What’s the difference of using between _root[“mc”] and declaring a variable to createEmptyMovieClip?

here’s of what I mean:

_root.createEmptyMovieClip(“toto_mc”,1);
_root[“toto_mc”]._x = 0;
_root[“toto_mc”]._y = 0;
_root[“toto_mc”].loadMovie(“ruban.swf”,1);

var toto = _root.createEmptyMovieClip(“toto_mc”,1);
toto._x = 0;
toto._y = 0;
toto.loadMovie(“ruban.swf”, 1);

Both seem to do the same. Does anyone have any ideas? I’m just curious to know…