DoubleLines

Some pages use DoubleLines to separate a DocumentMode OpeningStatement, thesis, or pattern at the top of a page and (usually ThreadMode) discussion below. The top part is generally the pages payload -- a short article on the page's title subject along with bibliographic information; while the bottom is meta-data about the page -- discussion, suggested changes, categorization, stories, indirectly related links etc...

Source: Wiki:DoubleLines