Fast Loading Time For Image

[Abbster22]

I know that there are many scripts (Jquery and Javascript) and CSS tricks that allow an image as a background to scale with the browser.

There's this one website that I find a very good example of what I would like to achieve, which is below:
http://g2geogeske.com/

I wanted to know on this website how they are able to have a huge image file like this website has download in 3 seconds or less?

[jscheuer1]

Once it loads once, it's in the browser's cache so should take almost no time to load again. For the first time though, 3 seconds is not unreasonable for an image of 278 KB. That's at 100mbps like my current connection. If you have fiber optic or cable or any of the G4 wireless, you probably have the same speed. Even at 56mps, common for many wireless, 3 seconds is still reasonable. The key is that it's the only image on the page. The others are background images, so presumably the image takes priority. But the background images are few and very small 3 to 18 KB abouts. Any decent multi-threading browser can get them during the 3 seconds it takes to get the large image.