Underscore files (_filename.pcf) control editable elements of your entire site. They are named with an underscore so that they will always display at the top of the Pages List view in Omni CMS when sorting alphabetically. This makes finding these site template files easy. Underscore files can control your sites top navigation and notification message. They also allow you to create breadcrumbs, side navigations, and a footer that can be nested inside of folders.