The main element represents the major content part of a document or application's body. Authors are not permitted to add more than one primary element in a document. Aside from the footer, header, and navigation elements, authors MUST NOT use the main element as a child of an article. The main element can be used to highlight a particular section of content without affecting other parts of the page design. For example, if a newspaper has a front page with an article that is longer than normal print space allows, the paper could use multiple columns to display the full story. The main element provides a way to distinguish this important piece of content while keeping the rest of the page simple and easy to read. When you use the tag, each instance within the same document should have only one main element. If you have several pieces of relevant information that don't require separate pages, but do need to be included in the same document, use the main element to separate them out into different sections. In HTML5, the main element can only appear inside a paragraph or another main element.