The term hypertext is used to refer to full-text indexing schemes which are more elaborate and, ideally, more useful in creating "links" or connections between related subjects or terms. [...] Hypertext allows the user to move from within one section of text to another, related section of text, without having to exit the current document (or section of document) and re-enter a new document. (O'Connor, "Markup, SGML, and Hypertext for Full-Text Databases--Part III" 130)