Headers and Footers are used for automatically putting things on every page on a document or on alternating pages, without having to put them in page by page. In a book you will have the number on every page. That is done by putting them into the Footer or Header. Sometimes you will see the name of the book or the chapter on every page. That is done with Headers and Footers. Sometimes the pages will alternate, with different things on odd and even pages. Sometimes you have the name of the book on one page, and the chapter on the other page, when you have the book open. Using Headers and Footers you can put other things automatically for every page, like the date or the time, or the author of the document.