In typography, a column is one or more vertical blocks of content positioned on a page, separated by gutters (vertical whitespace) or rules (thin lines, in this case vertical). Columns are most commonly used to break up large bodies of text that cannot fit in a single block of text on a page. Additionally, columns are used to improve page composition and readability. Newspapers very frequently use complex multi-column layouts to break up different stories and longer bodies of texts within a story. Column can also more generally refer to the vertical delineations created by a typographic grid system which type and image may be positioned. In page layout, the whitespace on the outside of the page (bounding the first and last columns) are known as margins; the gap between two facing pages is also considered a gutter, since there are columns on both sides. (Any gutter can also be referred to as a margin, but exterior and horizontal margins are not gutters.)