The search engine used underneath the SiteSurfer is intelligent about different types of information that describe a document. It knows that documents can have authors, keywords, titles, descriptions, text, dates, etc.
In HTML (the language of Internet documents), most of these attributes are defined in "meta tags". Advanced users can add their own meta tags to be indexed.
Simply type the name of the meta tag into the "Add tag name" field, and click the button. To remove a tag, select it in the list box, and click the button.