This accordion gives you the ability to modify the header and footer sections of your public site. When these sections are populated, they will appear on all pages of your site. In both sections, you can add text using the design tools in the Toolbar or you can put in text marked up in HTML.
For the header, many organizations do not add additional text. However, one common option is to add HTML code to make your logo a clickable link back to the home page of your organization's website.
The footer section can be used for a variety of purposes. You might want to include your organization's contact information, museum hours, featured thumbnail images, copyright statements, or donor/sponsor acknowledgements.