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Abstract : |
This powerful underlying concept is usually realized in both research and practical efforts within a nodelink model: nodes are the holders of content, and links are the means by which the content is given context. In this model, links are closely associated with navigation and mechanisms for traversal; they are a way to move from node to node, to keep readers focused on the current node or document, until they decide to move on to the next. We refer to this style of hypertext as document-centered hypertext. As systems and applications designers have gained more practical experience with hypertext, models of structure have grown more sophisticated, more expressive, and in many cases, more flexible than conventional node-link models. To address the needs of specialized applications, some models diverge entirely from stan-88 August 1995/Vol. 38, No. 8 COMMUNICATIONS OF THE ACM ypertext, 1 in its most general sense, allows content to appear in different contexts. The immediate setting in which readers encounter a specific seg-ment of material then changes from reading to reading or from reader to reader. Authors collect and structure materials to reflect their own under-standing or in anticipation of readers ? possible interests, needs, or ability to comprehend the substrate of interrelated content. 1 We use the term hypertext broadly, to cover both textual and multimedia content., |
