Explanation of the "LEVELs" parameter...?

Would someone please be so kind, and explain the concept of the Levels parameter… For some reason i just cant grasp it, and feeling pretty dumb :block:
I learned Flash by just “jumping right into it” (by need), and unfortunately I find myself bumping into terms I dont quite grasp.

*Example:
loadVariablesNum (“url” ,[color=Red]*level *[/color][, variables])

My current project includes trying to load a movie/swf when a user presses a button. The Flash Help says:
*[color=Black]“If you want to load a SWF or JPEG file into a specific level, use loadMovieNum() instead of loadMovie().”

[/color]*[color=Black]I’m not quite sure of which to use.

Any help / examples would be appreciated.

Thanks.

-kaanuki-
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