How do I apply a two-column layout?
On the Layout tab, click Columns, then click the layout you want. To apply columns to only part of your document, with your cursor, select the text that you want to format. On the Layout tab, click Columns, then click More Columns. Click Selected text from the Apply to box.
What do readers like about two-column layouts for documents?
Two columns makes it easier to have short lines, without resorting to small paper size, large font sizes, or huge margins. Thus you still get a high density of text per page, and it keeps page counts down (and the associated costs).