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For example , the capability of digital technology to enhance learner control over the pace and detail of information delivery has been claimed to have a positive affect on learning by many authors ( Dryden , 1994 ; Landow , 1992 ; Landow and Delany , 1991 , though see Hooper and Hannafin , 1988 , and Relan , 1991 for alternative viewpoints ) . In their introductory essay , Landow and Delany address the impact of such developments as the dematerialization of text ( which exists only as a piece of code ) and the manipulability of text-based computing ( searches , editing , comparison , and analysis ) , which shifts the balance of power from text to reader . the real and the imaginary ; from the internal and external realms of experience " ( Landow and Delany 1991 , 7f ) . Hyperlinks in hypertexts and hypermedia documents generally emphasise such intertextuality in a particularly neat way that is impossible in printed texts : they can lead directly from the hyperlinked terms , phrases or images to other contexts in which the same terms , phrases or images are meaningful , whether inside or outside the given work ( Landow and Delany 1991 ) . The sixteen essays collected in The Digital Word continue Landow and Delany 's exploration of the new fluid , digitized text begun in Hypermedia and Literary Studies ( 1991 ) , which focused on the linking of text , graphics , or sound into structures typically bound within a single computer or local-area network .