Books written in this fashion have the "choice element" in them, with an option to go to page xx if, or page yy else. These books can have a multitude of story lines and endings, but are limited, to the existing pages in the book, as to the number of options or story lines that can be followed.
Plays can also be written in a similar fashion, to enable the reader to work their way through, so that they end up at the outcome they have chosen.
The main advantage of a hypertext play, is that they can be used in such a way, to give the reader the ability to "jump" around the text of the script. This can be very useful, in order to analyse a play, such as Shakespeare's A mid-summer night's dream.
