Paddy Donnelly on an excellent article about the concept of "the fold" in web design:
We all know, people have learned to scroll. They did a long time ago, but still the 'everything needs to be above the fold' concept lingers on.
It's not new, and others have argued that there is no fold in a very compelling way. But today I had an discussion about this when someone mentioned, again, that a key element was below the fold.
We were looking at the website on my 13 inch MacBook Air. Fortunately, I had it connected to a 24 inch display, so I just dragged the browser to the bigger screen and presto! The whole thing was above the fold.
I then showed them the site on the iPad. And then on the iPhone.
It's time to move on. Scrolling is simple and everybody does it naturally. There is no fold.