Above the fold is the upper half of the front page of a newspaper or tabloid where an important news story or photograph is often located.
[1] As screen sizes vary drastically[2] there is no set definition for the number of pixels that define the fold.
Further complicating matters, many websites adjust their layout based on the size of the browser window, such that the fold is not a static feature of the page.
Many web site optimization efforts may be exerted in an attempt to gain the highest "search indexing" or "ranking" placement (as close to first place as possible) for directed term(s) or phrase(s).
Using natural or "organic" web site optimization practices has been the standard operating procedure for attaining higher indexing with the result being the web site appearing in the view area or "above the fold" of the search results pages and especially the first page.
The term is infrequently used in reference to resume and CV (curriculum vitae) layout, where the most crucial and relevant (to the job sought) information must be in the top third, alternately called the "hot zone", to catch the attention of the reader.