Way back when, when newspapers ruled the world and a Net was something used by fishermen and circus performers, "above the fold" was shorthand for a prominent story which would be featured on the top half of the broadsheet edition, or the visible portion of the paper when folded:
In the Internet age, it carries a similar meaning: a prominent story which would be featured on the top half of the screen, or the visible portion of the display before a user has to scroll down.
The "Above the Fold" note on the top of our pages indicates the top stories being covered that day, and provide links to either access the stories directly, or to advise the user to select the story from those rotating across the cover.