A header often shows the title of a document or the date it was created.

A footer is an area for information that appears at the bottom of a page in a word processing document.

A footer often shows the page numbers of a document.

Whatever you type into a header or footer will show up on every single page of the document. If you change the header on one page, the headers on other pages in that document will also change.

You'll practice adding headers and footers soon.