An interactive fiction (IF) game is almost like a fancy computerised version of a "choose your own adventure" book with more choices available. An interactive fiction game occurs all in text input and output, making it accessible to those using VoiceOver's spoken or braille interfaces. IF games are also turn-based rather than time-based, so if it takes the user several minutes or more to enter their portion of the text this won't affect the game. This makes IF games ideal for those who have difficulty with the pace of real-time games.
Wikipedia provides a sample transcript of a short IF game which gives the flavour of these games and TADS has an Introduction to Interactive Fiction which is longer.
One piece of fantastic news for Mac based interactive fiction players is that there's a brilliant client available called Zoom. As well as being free, Zoom is fully compatible with VoiceOver and also provides an option to have the text of a game spoken automatically as you play.
The most recent version of Zoom is currently not listed on the regular page - you can now download Zoom 1.1.4 which is more compatible with Leopard and has some bug fixes for the speech generation. It also has a built-in browser for selecting new games to download and play.
For those new to IF games, I suggest you look at Eric Eve's IF Games For Beginners list. Once you are thoroughly hooked, you can find enough freely downloadable games at the IFDB to keep you occupied for at least the next decade. After than, perhaps you can learn to write you own games!
- Ricky Buchanan