The entire thing is a theme, it sticks to a theme. The skins are what are used to make a theme, you make a theme, with skins. As an example, I shall make a peanut butter sandwich, now, I have bread, and the peanut butter sitting in front of me. Is it a sandwich? No, not until I spread the peanut butter on the bread, and stick the two pieces of bread together.
Same concept as the skin, theme thing, you get skins, and make a theme.
Battlefire. A wallpaper is part of a fucking theme.
He is using
Rainmeter to set up his theme. If you search his image you can find similar themes made from rainmeter skins.
Like this: <!-- m --><a class="postlink" href="http://fav.me/d55yc3z">http://fav.me/d55yc3z</a><!-- m --> and this: <!-- m --><a class="postlink" href="http://fav.me/d6ctga8">http://fav.me/d6ctga8</a><!-- m --> and this: <!-- m --><a class="postlink" href="http://fav.me/d54z5ky">http://fav.me/d54z5ky</a><!-- m --> and this: <!-- m --><a class="postlink" href="http://youtu.be/2FgDnHOFmTY">http://youtu.be/2FgDnHOFmTY</a><!-- m -->
The last one is a video from one of those I linked, showing how it works.
It is NOT just a background or a wallpaper, it is actually interactive, you can click things, bars change and stuff. It's real time stuff. It is NOT a wallpaper. It's a rainmeter theme.