Question

what is header footers

Answer 1

Space on top of pages in a document is called as a header.

Such spaces on bottom of pages is called as a footer.

Answer 2

A header refers to the section at the top of a page of a document that can bear a title, date, page number, a picture, our name, or anything we want.
A footer refers to the section at the bottom of a page that can bear exactly the same thing as header.

Hope this answer helps you.