(Originally posted to rec.games.mud in November, 1990)
Roy rewrote it almost immediately, and the next version, also in MACRO-10, was much more sophisticated. This one was definitely called MUD (I still have a printout of it). The database (ie. the rooms, objects, commands etc.) was defined in a separate file, but it could also be added to during play. However, the result was that people added new rooms that were completely out of keeping with the rest of the environment, and, worse, added new commands that removed any spirit of exploration and adventure that the game may have had.
In those days, memory was at a premium, and on Essex University's DEC-10 we had something like 50K maximum (36-bit words) to use. The game definition stuff took up too much memory, so Roy decided to ditch it. The program was also becoming unmanageable, as it was written in assembler. Hence, he rewrote everything in BCPL, starting late 1979 and working up to about Easter 1980. The finished product was the heart of the system which many people came to believe was the "original" MUD. In fact, it was version 3.
I had been helping Roy with the game-side of things for some time, starting with suggestions for version 1. Roy was mainly interested in the programming side of things, rather than the design of rooms, puzzles and so on. When he left Essex, I took over full control. At that point, there was no objective for the players, and only primitive communication. There was no points-scoring system, there were no mobiles, no containers, and even some of the infrastructure was missing (eg. two people in a dark room, one with a torch: the other still couldn't see). In terms of lines of code, Roy gave me about 25% of what was in the final program (mind you, it was the most essential 25%!). I added all the stuff about getting to be a wizard (which was previously 'debug mode' so implementors - Roy and I - could test out new room complexes we'd added.
Roy's reasons for writing MUD were twofold: to make a multi-player adventure game; to write an interpreter for a database definition language. The language he developed was rather crude, and I had to hack it to get it to do a lot of the things I wanted to do. This was partly because Roy didn't know the kind of things that would be needed from a game-design perspective, and partly because the multi-user aspect came to dominate the project. However, the core of the database definition language (MUD definition language - MUDDL) was all Roy's. I didn't add it, I added TO it.
Although Roy had written the basis of the system, it wasn't really a game, nor was it completely usable. Sometimes, the implication is given that I merely modified his program, or tidied up a few loose ends, whereas actually I wrote most of it (and unwrote some of it!). At other times, there's the suggestion that Roy just knocked together a basic shell devoid of anything really original or interesting; again, that's incorrect - Roy pioneered MUD programming, and had to design everything from scratch. So the writing of that first MUD was basically a team effort, and the way Roy and I expect to see it described is "MUD was created and written by Roy Trubshaw and Richard Bartle at Essex University in the UK", or words to that effect.
At this time, there was an experimental packet-switching system (EPSS) linking Essex University to ArpaNet in the USA. In Spring 1980, we got our first few external players logging in and trying the game out (one of whom I met recently by complete chance in a hotel in Annapolis, MD). There's a reference to MUD in an article on Zork in the December 1980 issue of Byte. Interestingly, it also mentions an earlier multi-player version of Zork, but neither I nor Roy were aware of it at the time. I've never found any other references to it, so I don't know how MUD-like it was.
MUD only had one database for the first couple of years, then I took out all the "generic" bits (eg. get/drop/quit commands, spells, common objects like doors & keys) and put them into a set of include files. I then wrote another game called Valley, using the MUD interpreter and the include files, but with another set of rooms and puzzles. Although I'm only a year younger than Roy, I was able to stay on at Essex and work on the system because I became a postgraduate (and, later still, a lecturer) there. Some undergraduate friends took the interpreter and include files (with my permission), and used them as a basis for their own games.
The first of these was Rock (based on Fraggle Rock, the TV show), but others that spring to mind were BLUD (very deadly), UNI (a simulation of the University, with spoof monsters for the members of staff), and MIST (about which you know). After I left Essex, I let them run MUD for two or three years for old time's sake, but after a while its code was adulterated by a new bunch of well-meaning undergrads, so I took it away; people were getting a false idea of what the game was meant to be like (and besides, they'd removed my name from the arch-wizard list!). The original MUD is back now, I understand, and will remain there until the DEC-10 is switched off (if it hasn't gone already).
The game was initially populated primarily by students at Essex, but as time wore on and we got more external lines to the DEC-10, outsiders joined in. Soon, the machine was swamped by games-players, but the University authorities were kind enough to allow people to log in from the outside solely to play MUD, so long as they did so between 2am and 6am in the morning (or 10pm to 10am weekends). Even at those hours, the game was always full to capacity. Thus, MUD became a popular pastime throughout the modem-using computer hobbyists of Britain. I also sent copies of the code to Norway, Sweden, Australia and the USA.
I could go on, but then we stop being early days and start being present days, so I won't! Suffice to say that the original game was licensed to CompuServe, where it still runs to this day, labouring under the name of "British Legends".