Gamebook

At the end of a text section, the reader is usually presented with a choice of narrative branches that they may follow, with each option containing a reference to the number of the paragraph that should be read next if the option is chosen. The reader may eventually reach a concluding paragraph which will bring the narrative to an end. In most gamebooks only one (or if more than this, a distinct minority) of the concluding paragraphs will end the narrative with a "successful" ending, with the others ending the narrative with a "failure" ending.

Gamebooks are usually written in the second person with the reader assuming the role of a fictional character. The titles are usually published in series containing several books, although individual gamebooks have also been published. While the books in many series are stand-alone narratives, others continue the narrative from the previous books in the series.

There are three types of gamebooks. The first is the branching-plot novel (an example of this is the Choose your own adventure series of gamebooks), which require the reader to make choices but are otherwise like a regular novel. The second type is the role-playing game solitaire adventure (an example of this is the Tunnels and Trolls series of gamebooks), which combines the branching-plot novel with the rules of a role-playing game, allowing the game to be played without a Gamemaster but requiring the purchase of separate manuals. The third type is the adventure gamebook (examples of these are the Fighting Fantasy and Lone Wolf series of gamebooks), which combines the branching-plot novel with simple role-playing rules included with each book.

The first gamebook was published in 1941, it was titled 'Examen de la obra de Herbert Quain'  by Argentinian author Jorge Luis Borges. It had 9 possible endings. 

Another early example of use of the form for literary experimentation is the work of American writer John Sladek, who towards the end of the sixties published the short stories Alien Territory and The Lost Nose: a Programmed Adventure.

At nearly the same time, Lucky Les, a book by E.W. Hildick published in 1967. The book allowed the reader to determine the fate of a fictional cat by making choices and turning pages accordingly.

Gamebooks didn't really get popular till the 1970's with the release of the Choose your own adventure series.