Hypertext exists solely on computers. Through common word processing we are now accustomed to text that can be formed and re-formed like a piece of clay, time after time. These texts and pictures might then be linked further. But the structure of ideas is not sequential. They tie together every whichway.
Electronic publications are often cheaper to produce than printed ones.
The publishers claim that the CD-version will be affordable even for smaller libraries, colleges and schools. Updating of technical documentation is much cheaper when stored on electronic media, since you don't need to reprint perhaps hundreds of books. One great advantage with source text stored in large databases is the possibility to execute very fast and flexible searches. Suppose you are writing an essay on stomach diseases through the ages. This could be a better method than microfilming or photocopying old brittle books, now deteriorating due to the acidic paper on which they were printed.