button instance

Whenever I use button, and need to set its property (visibility etc) with action script, i always have to put the button to a movie clip, and then named the movieclip intance. by that way i can do action to that button such as : setProperty(clipThatContainButton,_visible,0)
or clipThatContainButton._visible = 0

Question : can I target the button without having to place it into a movieclip ? what is the "Track As A button" option for ? it is in the button instance (right click button > intance > option)

thank you.