The Muddle programming languge is a member of the Lisp family. It started at MIT's Project MAC. It's hard to pin down exactly when development began. The first documented reference to it seems to be in the Project MAC Progress Report VIII at which covered the period of July 1970 to July 1971 although some have claimed as early as 1969 but provide no sources. The original MIT-DMS (along with other historically important systems like AI, MC, anmd ML) were KA- and KL-10 based PDP-10 systems running the Incompatible Timesharing System (ITS.) When they were retired in 1982, four KS-10 systems ("DECSYSTEM-2020") were put in their place in order to keep ITS running. These were retired from service around 1995. This mudman.git repository is named after the MUDMAN directory on MIT-DMS, which contained documentation about Muddle. Many people have worked on Muddle in one aspect or other over the years. These include (in alphabetical order by first name): Brian Berkowitz, Bruce Daniels, Carl Hewitt, Chris Reeve, Dave Lebling, David Cressey, Gerald Sussman, Greg Pfister, Jim Michener, Joel Berez, Marc Blank, Michael Broos, Neal Ryan, Roger Banks, Stu Galley, Sue Pitkin, Tak To, Tim Anderson and others that will probably never be known. This represents an effort to preseve information about the Muddle programming language by migrating the documentation from aging books into modern formats. Despite efforts to preserve the documentation as much as possible one change is made: Changing MDL references back to Muddle. In talking to people that originally worked on the language it was always called Muddle. The Muddle name was in the MIT AI Lab's tradition of naming Lisp dialects with somewhat sarcastic names. Reference other names from there like Planner, Scheme (which was actually named Schemer but ITS limited file names to a maximum of 6 characters), Conniver, etc. and it shows a pattern. Chris Reeve says that the Muddle name came from the nickname of the Project MAC Dynamic Modeling Group from either Gerald Sussman and/or Carl Hewitt, which was "Dynamic Muddlers." The MDL name was actually invented by an administrator at the project that feared losing DARPA funding over a funny name. No one actually called it "MDL" except in documents DARPA might see and even then they wrote "MDL" but said "Muddle." The name "MIT Design Language" is, consequently, a backronym. The Muddle name itself eventually got a backronym of "MAC's User Defined Data and Language Evaluator", with "MAC" representing "Project MAC". Changing the MDL references back to Muddle is believed to be in support of the original naming decision of those that made the language, especially since there are no longer any DARPA funding concerns. The documents in this repository, including this one, are made following the CommonMark specification: . Converting them to other formats requires that cmark, which is the reference implementation of Commonmark in C from or Pandoc from or some other program that can understand CommonMark be installed on your system. --- This document by Jason Self is licensed under the Creative Commons Attribution-ShareAlike 4.0 International Public License and all future versions: .