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Guide was a hypertext system developed by Peter J. Brown at the University of Kent in 1982. The original Guide implementation was for Three Rivers PERQ workstations running Unix. The Guide system became the third hypertext system to be sold commercially, marketed by Office Workstations Ltd (OWL) in 1984 and later by InfoAccess. "Guide" won Brown the British Computer Society's award for technical innovation in 1988. He retired in 1999 and died of cancer in 2007, according to a tribute page at the University of Kent website.
Ian Ritchie, founder of OWL, presented a Ted talk in 2011 describing his missed opportunity to convert Guide to a graphical browser for the Web at its inception in 1990, titled "The day I turned down Tim Berners-Lee." 
In September 1986, Guide was ported by OWL to the Apple Macintosh, and in July 1987 to Microsoft Windows. (In 1987 Apple had begun giving away its own graphical programming system, HyperCard, which had some hypertext features.) According to news reports in 1988, OWL announced plans to release a version of Guide for the IBM PS/2 line of computers under the name "Hyper Document," in competition with Hypercard on the Apple Macintosh.
OWL gradually shifted the focus of Guide from a low-cost "hypertext word processor" to a more expensive CD-ROM multimedia development system.
Unlike most hypertext systems, the main link mechanism in Guide is based on replacement, meaning that when following a link, the current node breaks open, making room for the destination node. The anchor of the link is replaced by the contents of the destination node. One can close the destination node, which means that it is once again replaced by the text of the anchor. Thus, the basic method of navigation using Guide was the expansion button, in which a section was replaced when selected and in which an expansion would provide additional levels of detail. This allowed the user, whether they were a document author or a reader, to expand and contract a document, viewing the desired level at any time, not unlike viewing methods used in Adobe Acrobat files. Using this method means that the structure of the document must be strictly hierarchical.
Guide supported pop-ups for small annotations, and so-called jumps, which behave like the follow-link operation in most hypertexts (as in van Dam's FRESS system). The jumps allow for the creation of non-hierarchical links.