For most pages in an instance there would two frames that are displayed:
Top frame that shows the instance banner as well as the user name and other icons
Left frame that shows the filter navigator
This article details the procedure on how to hide these two frames.
The frames are displayed due to the URL of the page containing the "nav_to.do?uri=" parameter. So in order to not display these frames users can manually remove that parameter from the URL or update the processes that generate the URLs to not contain that parameter.