CircleMUD is a multi-user dungeon game system (MUD) written by Jeremy Elson, originally at Johns Hopkins University's Department of Computer Science (I graduated in May of 1996). CircleMUD is a derivative of DikuMUD Gamma 0.0, which was written in 1990 at DIKU, the Department of Computer Science at the University of Copenhagen, by Katja Nyboe, Tom Madsen, Hans Henrik Staerfeldt, Michael Seifert, and Sebastian Hammer.
A MUD (Multiple User Dimension or Multiple User Dungeon) is a computer program which allows Internet users from around the world to connect to it, create fictional characters for themselves, and then interact with other real users as well as computer-generated entities in a virtual environment. Users can explore their virtual world, talk to or perform actions with other human players, roam through dangerous monster-infested areas, solve puzzles, and seek treasures. Player-to-player interaction is common in modern-day games but MUDs were among the first to do so. DikuMUD is a particular class of MUD which tends to be combat-oriented with a look and feel similar to some (non-computerized) role-playing games. CircleMUD is a derivative of DikuMUD. While Circle still retains the "look and feel" of the original DikuMUD, it has dozens of additional features and bug fixes, and much of the code has been rewritten to be more flexible, efficient, easy to understand, and easy to extend.
CircleMUD is freeware! You can download all of Circle's source code, libraries and documentation absolutely free. The code compiles under most versions of UNIX (including Solaris, SunOS 4.x, Ultrix, Linux, AIX, and HP/UX), Microsoft Windows (Windows 95 and Windows NT), IBM OS/2, Mac System 7/8, OpenVMS, and the Amiga.
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