19 Aug 2014


The Multicians web site presents the story of the Multics operating system for people interested in the system's history, especially Multicians. The site's goals are to

  • preserve the technical ideas and advances of Multics so others don't need to reinvent them.
  • record the history of Multics, its builders, and its users before we all forget.
  • give credit where it's due for important innovations.
  • remember some good times and good people.

The Multicians web site contains 425 HTML files (see the Site Map) comprising over 1,000,000 lines, 22 PDF files, and 399 graphic images. The site has benefited from the contributions of many authors. Contributions are invited: if you have a correction, fact, date, name, anecdote, or picture, please share it with Multicians everywhere by sending mail to the editor.

Open Source for Multics is hosted at MIT, courtesy of Bull HN. It is available "for any purpose and without fee" provided that the copyright notice and historical background are preserved in all copies.
MIT held a 50th anniversary celebration of Project MAC/ LCS/ CSAIL in Cambridge, MA on May 28 & 29, 2014. There was also an associated Multicians' reunion event on May 29. At the reunion, Michael Pandolfo proposed activities leading up to the 50th anniversary of Multics in 2015.
A project to create a software simulator for the Multics CPU, started by Harry Reed, has run several million instructions of a Multics cold boot, and has begun to process a page fault. Volunteers are welcome.

Multics (Multiplexed Information and Computing Service) was a mainframe timesharing operating system begun in 1965 and used until 2000. Multics began as a research project and was an important influence on operating system development. The system became a commercial product sold by Honeywell to education, government, and industry.

Multics was a prototype of a Computer Utility, providing secure computing to remote users at their terminals. Multicians still miss the elegant, consistent, and powerful programming environment; some Multics features are only now being added to contemporary systems.

Recent Changes
History: Additional clarifications and details.
Project MAC: Moved Project MAC history to its own page.
Bibliography: Added two more MAC TMs.
Bibliography: Added an interview with Roger Schell and two papers by John McCarthy.
USGS Site History: Updated with info from Dave Jordan.
Bibliography: Added 11 Project MAC Progress Reports.

all changes