The early days of ebooks. Interactive electronic books that came on either a floppy disk or a CD ROM from a company named Voyager.
From Apple’s Summer 1993 catalog:
Voyager introduces a dynamic new way to read exciting best sellers. Expanded books combine the most enjoyable aspect of traditional books with Macintosh benefits such as variable type size, customize word search and indexing, and on-screen pop-up annotation-even the ability to read at night without the light on!