Note: "Dungeon" redirects here. For other game called Dungeon, see Dungeon (disambiguation).
- Zork was originally written in an obscure LISP-variant language called MDL (and sometimes informally referred to as 'Muddle'), designed at MIT, which ran on the operating system ITS (also designed at MIT) for the PDP-10, a large computer of the 1970s. Matthew Russotto has created an MDL interpreter that is sufficient to run this original Zork, called Confusion. (The link gives the source, a Windows executable and instructions on how to get it to work with the original Zork MDL program.)
- A DEC (Digital Equipment Corporation) engineer, Bob Supnik, acquired the ITS source code for Zork and converted it to Fortran. This version is commonly known as 'Dungeon' and is widely available, both as Fortran and as mechanically converted C source code. Several versions can be obtained from the games/pc and games/source directories of the IF-Archive.
- An Inform 6 port of the original MDL source code has been created by Ethan Dicks: zdungeon.z5.