Categories of interactive fiction

Find a pack of cards. Take a card at random. Replace, shuffle well, draw again. If you get the Queen of Spades twice in a row, you are born dead. Go to 0.
-- Kim Newman, Life's Lottery

I have been noodling about with a visual model of the various sorts of interactive fiction, which I have here:

Visual model

Some examples of each:

"IF Games" (world state stored, high freedom of input): Zork, Curses, Pick Up the Phone Booth and Die

"Gamebooks" (world state stored, low freedom of input): the Lone Wolf series, the Fighting Fantasy series

"Hypertext" (world state not stored, low freedom of input): Patchwork Girl

"CYOA [Choose-Your-Own-Adventure]" (world state not stored, low freedom of input): the series by the same name, Life's Lottery

"Chatterbot" (world state not stored, high freedom of input): ELIZA

Caveat #1: The term "gamebooks" is sometimes generalized to include choose-your-own-adventure style books. I have separated it here to indicate that there is some sort of world storage state, generally referring to a player inventory and RPG-like statistics.

Caveat #2: I am using "chatterbot" here to refer only to "dumb" chatterbots with no memory beyond the previous command.

Caveat #3: These categories aren't exactly parallel. ELIZA has a great deal more freedom of input than any IF game; gamebooks tend not to store nearly as much detail as an IF game. It may help to think of the corners as directions rather than absolute points.

Some relatively interesting effects can be attained by adding more variables. For example, here's what happens if you care about whether or not the user is a character in the story or not:

Visual Model #2

The left square represents "the user is a character in the story" and the right square represents that "the user is not a character in the story".

The hypertext and CYOA categorize get separated, so that's rather pleasant.

"Expert model" refers to things like a taxonomy system that answers simple questions and routes down a branching tree (what color are the feathers on the bird? does it fly? etc.) Unfortunately, expert models tend to be in truth limited in choice (even though they have free entry) so the position is filled somewhat uncomfortably.

"Expert system with world model" refers to a system like SHRDLU which resembles a chatterbot but keeps track of world state. Nick Montfort cites it in his book Twisty Little Passages as an early form of IF, and by this model his statement is accurate (although it still does not get lumped together with "games", which makes logical sense).

"Advanced hypertext" is a word I invented because I was unable to come up with anything that met the criteria. It would require a hypertext that stores information about the world state; for example, perhaps if the user picks links related to death scenes across the entire hypertext become darker. There are some Japanese games that appear to come close like Radical Dreamers but I don't know the genre in detail enough to make an authoritative statement here.

"Interactive poetry" is another word I invented, and really only matches (at the moment) with Andrew Plotkin's work The Space Under the Window. (The title of this weblog also hints at a work in progress of my own which falls into this category.)

The blank spaces and invented words may seem a bit of a stretch, but it's really the blank spaces on the map that interest me most. Different variables like "RPG elements" and "graphics" have brought up things of interest. I'll cover these results in the future.