The Expanded Books Project was an undertaking at The Voyager Company during 1991, that investigated ideas on how a book could be presented on a computer screen in a way that would be both familiar and useful to regular book readers. The Expanded Books focused on perfecting font choice, font size, line spacing, margin notes, book marks, and other publishing details to work in digital format.
Much of the original impetus for the project, however, dated back a year earlier to a small meeting on digital books that Voyager sponsored on Bloomsday, 1990, attended by various pioneering multimedia and hypertext experts. Voyager had earlier released a successful CD companion to Beethoven's 9th Symphony, and Voyager President's president Bob Stein had obtained a grant to work on creating a similar product for literature.   At this meeting, the consensus emerged that, to overcome the relative inconvenience of being tied to a low-resolution and cumbersome digital display, digital books would have to offer "added value". Florian Brody, head of the Expanded Books project, was the first to have the idea to design the digital books specifically for the then-new Apple PowerBook 100, which Apple had donated to the Voyager Company. 
The actual programming for the initial products happened over a relatively short period, between October and December 1991; the first three book titles (The Complete Hitch Hiker's Guide to the Galaxy, The Complete Annotated Alice, and Jurassic Park) were released at MacWorld San Francisco in January 1992. These books and their successors relied upon a "book engine" that provided a simple but powerful feature set: various convenient and simple search methods, the ability to switch between large print and normal print versions, various unobtrusive navigation tools (such as a chapter menu that dropped down from the chapter heading on each "page"), a margin area on each page in which readers could write notes, and, interactive annotations. For example, Moby Dick included a sound clip of the sea as an annotation , and The Annotated Alice provided pop-up annotations derived from both editions of Martin Gardner's work.   However, some readers found these annotations unwieldy and difficult to navigate, with poor usability. 
"Expanded Books" was not initially the definitive title of the product range. One other favored contender was "Power Books", but that idea died when Voyager was told Apple's about-to-be-released notebooks were to be called PowerBooks. Hence, the original project name became the product name.
Between February 1992 and August 1992, Voyager created The Expanded Books Toolkit, which allowed authors to create their own Expanded Books. Voyager themselves went on to produce over 60 books as Expanded Books; the underlying software was also used in CD-ROMs such as A Hard Day's Night, Salt of the Earth, and Macbeth. 
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