What is a "header" in document formatting?

In document formatting, a header is defined as text that appears at the top of each page in a document. This feature is commonly used in formal documents, reports, and essays to provide consistent information across multiple pages, such as the document's title, chapter titles, or the author's name. Including this information in a header helps readers navigate the document easily and maintains a professional appearance by ensuring that important details are readily available each time a new page is turned.

The other options describe different elements of document formatting. For instance, text that appears at the bottom of each page is referred to as a footer, while text in the margins may pertain to annotations or notes, which do not constitute a header. Text that appears on the cover page is specifically designated for that first page, which typically contains introductory details about the document, distinguishing it from the consistent layout provided by header text throughout the body of the document.