is it possible within a page ex domainname.com/offers to be a menu with links and when selecting one link from the menu to load the document or image or pdf within the same page(domainname.com/offers) instead of create a new one that will contain only the document?

i want to display it in a certain place of my skin layout

yes i know about the IFrame module and am using it in other parts of the site.

but my question is that 

i want on the left corner of the page (domain.com/offers) to be the links(menu). by selecting one of the links to be display inside my side but on the same page(domain.com/offers) on the content pane and not redirect me to other page and not all my document to be display all the time on the page.

by selecting a link only this document to be diplay

with iframe the document is be display and if i want to display 5 documents are all be display the same time.