Metagaming was the innovator of the pre-programmed adventure. Those adventures allowed for solitary role-playing games, as you moved from paragraph to paragraph within the adventure module, depending on the options you selected.
The idea of the pre-programmed adventure spawned a whole industry of pick-your-path adventure books, everything from adventure novelizations to solitary D&D adventures.
The Fantasy Trip: Death Test was the first pre-programmed adventure ever published. While that adventure was designed for solitary and referee-less play, a gamemaster could also run it. You played the part of an adventuring party, fighting your way through a labyrinth in an attempt to impress the local Warlord. If successful in exiting the labyrinth, you were offered a job with the Warlord, based on how well you did within the maze.
Death Test was a lot of fun, in the day. I'm sure that was due to the innovative nature of the pre-programmed adventure product, in addition to the fact that this used the simple combat rules of The Fantasy Trip.
Like the microgame "game design", pre-programmed adventures all but disappeared from the mainstream of entertainment and gaming. They were replaced by computer games and, eventually, massively multiplayer online role-playing games. The reasons for that are pretty straightforward. Computers could do what the players did (navigating between adventure episodes, and keeping track of the gaming minutae), and you got pretty pictures, besides.
The downside to those pre-programmed adventures was that you only had a limited number of options to choose from, in navigating the story. This was a problem for those that preferred the game-mastered approach to rpgs, as a good game-master would allow you to do something outside of the pre-planned options. In addition, many of the products suffered from poor editing: you would often find "path orphans", where the editors had either forgotten to direct you to the next paragraph, or forgot to provide the reference to that particular paragraph.
The nice thing about those pre-programmed adventures was that they were very "details-light", meaning they were easy to embellish, change and augment.
EDIT: I stand corrected. Buffalo Castle, for Tunnels & Trolls, was first issued in 1976, and appears to be the first solo adventure ever published, pre-dating the Metagaming products by roughly two years.
Before Metagaming collapsed, they published no less than eight pre-programmed adventures, under the Microquest line, starting with Death Test and Death Test 2, and branching out to other adventure genres, such as proto-historical fantasy (Grail Quest) and Science Fiction (Security Station).
Metagaming popularized the "micro-game" format, with such firms as TSR, Operational Studies Group, Mayfair Games, Steve Jackson Games, Task Force Games, Heritage USA, and SPI all jumping into a format, which ultimated proved to be commercially unviable.
For an interesting trip down memory lane, you may want to visit The Maverick's Classic Microgames Museum, at http://maverick.brainiac.com/cmm/cmm_index.html which hosts cover images of most of the micro-games ever published.