Development

Art of Building - Guide, technical tips and resources for MUD building and administration.
The Builder's Clan - Builder and administrator resource site for MUDs.
How to Learn MOO Programming - Annotated list of tutorials in MOO programming, intended for non-programmers.
MOO Database Browser - Command-line and web-based tools to view information in MOO database files which are not executing.
MOO Hardware and Software Requirements - Information about the requirements to run a MOO.
MOO Programmer's Quick Reference Sheet - A cheat sheet of the vocabulary used in MOOs. Cryptic for non-programmers.
XYZZYnews: Dungeons, Dragons, Shovels, and Telepathy - A brief look at MUD design, by Miron Schmidt.