Headings, if effectively used, provide a structural skeleton that enables readers to see the logic and flow of a document at a glance. Underline the words if effectively used. Most students use headings. Only rarely do we encounter a student who has been taught that an essay should be one long string of text unbroken by headings (if you were taught this, now is the time to unlearn it). Many, however, use headings ineffectively. Here are some guidelines for using headings.