ZZT is an ANSI-based computer game, created in 1991 by Tim Sweeney, of Epic Games (then Epic Megagames), who later designed Unreal. It remains one of the most popular DOS game creation systems. ZZT itself is not an acronym for anything; its title was simply chosen so it would always appear at the very bottom of newsgroup listings. However, it was later jokingly mentioned by Sweeney as being short for Zoo of Zero Tolerance, which has mistakenly become a popular belief.
ZZT's graphics were obsolete before it was even created; it used the same style of text-mode graphics that Kingdom of Kroz used 4 years earlier. However, ZZT managed to become fairly popular because of its integration of a simple but effective object-oriented scripting language known as ZZT-OOP. At the time this was groundbreaking, as most functionality in prior games had been hard-coded. The language allowed extensibility that no other game was able to provide, and allowed a large degree of community involvement that extended far beyond simply creating level terrain with the built-in editor, but rather involved writing programs to make the game run.
Originally ZZT was shareware, with only one of the four level-sets or "worlds" released without payment. The level released with the shareware copy is called Town of ZZT. The shareware versions also included Demo of ZZT, which displayed the basic features of ZZT worlds, and Tour of ZZT, which allowed the player to view select rooms (some playable) of the four worlds. Three different versions of shareware ZZT were released, with three corresponding registered ZZT versions. With about 30,000 registrations worldwide, ZZT was successful enough to finance the production of Jill of the Jungle, a game seen as Epic Megagames' answer to Apogee classics such as Duke Nukem. However when the game became obsolete it became freeware, with all four worlds of the registered version released for free. The worlds are: "Town of ZZT", "Caves of ZZT", "Dungeons of ZZT", and "City of ZZT"; they can best be described as adventure games.
