Glossary

The names “Medley,” “Interlisp-D,” “Interlisp.org,” “Common Lisp,” etc. are often used in confusing ways. We’re talking about a lot of different things that evolved over decades. These are cemented in by usage in different publications over time. We hope this glossary of terms will help.

Vocabulary and relationships

AltoLisp
An (unsuccessful) attempt to build a Lisp-based OS for running Interlisp on an Alto.
Carol, Fugue, Harmony, Intermezzo, Koto, Lyric, Medley
Named releases of Interlisp-D. All are obsolete except Medley.
Common Lisp
The subject of a 10-year standards process to converge multiple dialects of the Lisp language. Strong influences from many Lisp dialects, including Interlisp.
Common Lisp the Language
Book by Guy Steele with two editions:
  • CLtL1 – edition 1, 465 pages
  • CLtL2 – second edition, 1029 pages
Common Lisp dpANS
The ANSI Standard for Common Lisp.

Starting with the Lyric release of Interlisp-D and then the Medley release, the implementation of Medley included implementations of Common Lisp (CLtL 1) as well as the Interlisp dialect in a single development environment; this was made possible by using the (Common Lisp) “package” feature to allow both dialects to be intermixed.

Dfasl
A compiled form of Medley Interlisp files with the extension “.dfasl”.
DLISP
By Warren Teitelman: a first attempt at building a “Display” (GUI) with Interlisp running on MAXC (a PDP-10 clone) connected by Ethernet to a Xerox Alto acting as a graphics terminal.
Dorado Lisp
The reimplementation of the AltoLisp microcode on the Dorado – a research prototype.
Fugue
An obsolete named release of Interlisp-D.
Harmony
An obsolete named release of Interlisp-D.
Intermezzo
An obsolete named release of Interlisp-D.
Interlisp
A GitHub “organization” with ~20 repositories, see https://github.com/Interlisp
Both a language and, in some cases, the implementation of that language. Usually used with some other wording or refinement.
Interlisp: The Language and its usage
A book by Steve Kaisler which describes Interlisp of the 1970s & 80s.
Interlisp.org
The project’s Internet domain name, used for its websites and email addresses.
Interlisp-10
The first implementation of Interlisp for the Digital Equipment Corporation (DEC) PDP-10 / Tenex.
Interlisp-360
Implemention of Interlisp for the IBM-360.
Interlisp-D
What Dorado Lisp became. The D stood for both “Display” and “D-machine”. An implementation of
  • Interlisp the language
  • The Interlisp programming tools
  • A Graphical User interface to Interlisp programming development
  • A large number of tools, utilities, games, screen-savers
  • A Lisp-based operating system for D-machines which, when coupled with microcode implementation of a Virtual Machine, allowed the D-machines to operate as a personal workstation. Each D-machine had its own microcode with different configurations and micro-instructions.
Interlisp-VAX
Implementation of Interlisp for Digital Equipment Corporation VAX systems.
Koto
An obsolete named release of Interlisp-D.
Lcom
Used as a file ending, xxx.lcom, for compiled Medley files.
Lyric
An obsolete named release of Interlisp-D.
Medley
The final named release of Interlisp-D.
Medley 1.0, Medley 2.01, Medley 3.5 numbered releases of Interlisp-D
At some point the name Interlisp-D was retired and Medley used to name the software.
Maiko
An implementation of the functions of the D-machine microcode, but written in C for the Sun Microsystems SPARC processor workstation, initially developed by Fuji Xerox. Subsequently ported to little-endian processors and other operating systems.
SDL
Structured Design Language.
Sysout
A file containing the saved state of Interlisp virtual memory.
X11
The X Window System.

Organizations

BBN
Bolt, Beranek, and Newman, a Cambridge, Mass. consulting firm which sponsored the creation of BBN Lisp, Interlisp’s immediate ancestor, as well as the Tenex operating system.
Xerox PARC or just PARC
Palo Alto Research Center, which continued in collaboration with BBN on (renamed) Interlisp. PARC developed the Alto and Dorado. Now part of SRI International.
SRI International
A non-profit scientific R & D institute, headquertered in Menlo Park, California.
Xerox Electro-Optical Systems (XEOS)
A former Xerox division supporting government customers.
Xerox Artificial Intelligence Systems (XAIS)
The former Xerox division working to commercialize Xerox workstations running Interlisp-D.
Rank Xerox
Xerox’s European subsidiary, a joint venture of Xerox Corp. and the Rank Organization, which sold Interlisp-D workstations in Europe.
Fuji Xerox
Xerox’s Japanese subsidiary, owned jointly by Rank Xerox and Fujifilm Corp., responsible for selling and supporting Interlisp-D systems in Japan.
Envos
Company founded in 198x to take on the Lisp business from Xerox. Closed within 10 months and folded back into Xerox.
Venue
Company founded by John Sybalsky, former Xerox and Envos employee, which obtained a license to create and distribute derivative works of Maiko and Medley.
Medley Interlisp Project
Began late 2010’s with Nick Briggs getting Maiko to run on macOS. The group expanded and began holding weekly online meetings in 2020. Subsequently ported Maiko (and therefore Medley) to Linux, Windows, and other operating system. Maintains a mailing list for developers and interested users, sponsors the maintenance of an exhaustive bibliography and the very website where you’re reading this.
InterlispOrg
A California-registered non-profit organization (DBA Interlisp.org) Established August 2021. 501c3 EIN 87-2528093 California registered charity CT0278267. The Board of Directors consists of Larry Masinter, President; Ron Kaplan, Treasurer; and Herb Jellinek, Secretary.