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Hypermedia Cooper and Davis What Is Hypermedia? The combination of text, video, graphic images, sound, hyperlinks, and other elements in the form typical of Web documents. hypermedia is the modern extension of hypertext, the hyper linked, text–based documents of the original Internet. Hypermedia and Hypertext Hypermedia is an acronym which combines the words hypertext and multimedia. Hypertext is defined as a database that has active cross-references and allows the reader to “jump” to other parts of the database as desired. Hypertext is the concept of interrelating elements (linking pieces of information) and using these links to access related pieces of information. Hypertext is a collection or web of interrelated or linked nodes. Hyperdocument Below is a simplified view of an extremely small hyperdocument, having only five nodes and seven links. This figure also shows that links are tied to a specific point (or word or region) within a node, called an anchor. Historical Perspective 1945 Vannevar Bush- first article on hypertext-the mechanical Memex system. 1960s Theodore Holmes Nelson coined the terms hypertext and hypermedia. Xanadu system 1968 Douglas Engelbart first distributed, shared screen, collaborative hypertext system at the Fall Joint Computer Conference. 1970s and 1980s other prototype and commercial hypertext systems appeared-Document Examiner, gIBIS, Guide, Hypergate, HyperTIES, Intermedia, MacWeb (by LIRMM), Max, Neptune, NoteCards, PHIDIAS, StorySpace, Writing Environment and ZOG/KMS. Historical Perspective Cont. The first major hypertext research conference, ACM hypertext’87, was held in April 1987 in chapel hill, USA. 1990s, HyperG (now called HyperWave) and the World Wide Web (WWW) appeared the first distributed hypertext systems to take full advantage of the Internet after NLS/Augment. Hypertext Components Nodes Composites Link Anchor Link Markers Links Hypertext Features Navigation features-they include browsing (link traversal), backtracking, standard content-based query, and structural query based on interrelationships. Annotation features include bookmarks, landmarks and comments. Structural features enable navigation through local and global overviews, and along recommended paths and guided tours of interrelated items. Hypertext Subfields Adaptive hypertext Hypertext design Evaluation Writing Hypertext functionality Open hypertext systems and standards Hypertext Subfields Adaptive hypertext systems employ a user model to customize node content and filter the available link set. Adaptive hypertext systems try to guide users towards interesting and relevant information and shield them from irrelevant information. Hypertext design concerns analysis and design methodologies for creating hypertext systems. Hypertext design differs from standard design techniques due to its emphasis on links as first class objects and navigation. Evaluation techniques judge the ability for users to navigate effectively within a hypertext web and remain oriented when jumping into the web at random (e.g., to a node found by a search engine). Subfields Authors of hypertext literature (novels, short stories and poetry) work in a non-linear creativity space in which they design not only content, but also link structure, structural features and navigation. Hypertext Functionality group (HTF) studies techniques for applying hypertext constructs and features to the everyday, non-hypertext applications found in business, engineering and personal applications. Open Hypertext Systems group (OHS) studies ways for different hypertext systems to coordinate information and services over the Internet.