The “fold” is the point on your website where the page gets cut off by the bottom of a user’s monitor or browser window. Anything below the line can be scrolled to but isn’t seen right away. Search engines place some priority on content above the fold since new visitors will be seen right away. Having too many ads above the line can be seen as a negative issue, too. (See Panda).
What should we put above the fold?
When you are designing a web page you must consider putting the most important elements like headlines, videos, images right at the beginning and transfer the secondary element to the rest of the page.
Also, I strongly suggest putting an element right on the line, as the user will only see half of the element. This will let the users know that there are more on this page and they should scroll down.