They are known as the Header (top) and the Footer (bottom). Unless enabled, they do not appear on the printed page, and are outside the page body area that can contain printable text. Use Word's Help for more instructions.
Maybe the number of the page?
a heading
a heading
a heading
Magnifying a page does not affect the printed document unless there is a very bad problem with your computer and/or printer.
It is the Footer.
The margin
Text that appears at the bottom of each page is called a footer.
The view that puts a blue line around each page that would be printed is the Print Layout view. This view displays the document as it will appear when printed, including margins and page breaks, helping users to visualize the final output.
The information that will appear at the top of every printed page is typically called a header. This can include details such as the document title, page number, date, or author's name. It provides context and organization to the printed document.
page printed between print jobs
Footnote is printed at the end of the document and Footer is printed at the bottom of each page.