Any Designer can answer me? Is there any difference between artwork and visual? if yes, answer me, what is different ? if no, answer me why ?

I am not sure what do you mean about visual, but visual stands for anything could be seen, and artwork any piece of art made using one of art principles.

As per wikipedia and wiktionary:

Artwork (also known as art layout drawing) is a type of drawing that serves a graphical representation of an image for its reproduction onto a substrate via various processes, such assilkscreen, label making and other printing methods. Transfer of the image often involves a photographic process.

Noun[edit]

visual (plural visuals)

Any element of something that depends on sight.

An image; a picture; a graphic.

(in the plural) All the visual elements of a multi-media presentation or entertainment, usually in contrast with normal text or audio.

(advertising) A preliminary sketch.

Your question is not clear actually.

If your mean of visual "What we see" then it depend on artist's skills. 

Visual is "what we see" and artwork is the first step of making anything or immagination. 

Artwork is real work area, whose final output work area will be same with artwork area, And Visual area can be small or large than Artwork area which we see on screen.

Do you mean "The Difference Between Visual Art and Graphic Design"?