Web users spend 80% of their time looking at information above the page fold. Although users do scroll, they allocate only 20% of their attention below the fold.
There has always been a lot of talk in the web design circle about the “page fold” concept and the significance of keeping the most important information within a page’s initially viewable area. (For those who are not familiar: “above the fold” simply means "viewable without further action.")
During the first years of internet people didn’t scroll at all. Over the time this has changed but to some extent.
The good news is that users are scrolling today. However, you don’t have to ignore the fold and create endless pages. Why? Firstly, long pages are not effective enough because of the users’ limited attention span. And secondly, you will be able to attract and keep users’ attention with the stuff above the fold rather than below the fold.
Scrolling beats paging
if you have a long article, it's better to present it as one page piece instead of splitting it across multiple pageviews. Scrolling beats paging because it's easier for users to simply keep going down the page than it is to decide whether or not to click through for the next page of a fragmented article.
But even in this case, always make sure that anything truly important remains above the fold.
What Eyetracking Data Shows?
An eyetracking research conducted by Nielsen Norman Group, reveals how much users looked at different parts of a Web page.
The research clearly shows: users’ attention is focused at the top
According to this study, user viewing time is distributed as follows:
Above the fold: 80.3%
Below the fold: 19.7%
Scrolling Behaviors
The study also examined users’ behavior when they do scroll down an entire page, which happen seldom though.
The left gaze plot reveals an interesting fact: the last element in a list often attracts additional attention. The first few items are definitely the most important, but the final item gets more views than the one before it.
The two other gaze plots show more common scrolling behaviors: intense viewing of the top of the page, moderate viewing of the middle, and fairly superficial viewing of the bottom. (It has been picked examples where users scrolled more or less all the way down — often there's no viewing of the bottom because users don't scroll that far.)
Design Implications stated by Jakob Nielsen:
"The implications are clear: the material that's the most important for the users' goals or your business goals should be above the fold. Users do look below the fold, but not nearly as much as they look above the fold.
People will look very far down a page if (a) the layout encourages scanning, and (b) the initially viewable information makes them believe that it will be worth their time to scroll.
Finally, while placing the most important stuff on top, don't forget to put a nice morsel at the very bottom."