Browse Definitions:

Multics (Multiplexed Information and Computing Service)

Contributor(s): Simon Smith

Multics (Multiplexed Information and Computing Service) was a mainframe time-sharing operating system that was developed in the 1963-1969 period through the collaboration of the Massachusetts Institute of Technology (MIT), General Electric (GE), and Bell Labs. Multics was the first or one of the first operating systems that used page-segmented storage. The operating system was written in PL/I and ran on GE hardware. By 1970, Bell Labs had withdrawn from the project, and Honeywell, which had bought GE's computer division, continued as the hardware provider. Support from the Advanced Research Projects Agency helped sustain the project.

In 1973, Honeywell announced a commercial system, the 6180, consisting of two processors that ran at 1 MIPS each, 768 kilobytes of memory, an 8 megabyte bulk store, a 1.6 gigabyte hard disk, 8 tape drives, and two communication controllers. The price was about $7 million. Later, a multiple disk system called the New Storage System (NSS) was added. In 1977, Honeywell offered the first commercial relational database, the Multics Relational Data Store (MRDS).

Over time, Multics customers included General Motors, Ford, and Industrial Nucleonics (later AccuRay). By the late 1980s, efforts to migrate Multics to more strategic processor architectures such as Intel's had failed and Honeywell transferred maintenance to one of its last customers, the University of Calgary, which has passed it on to a local company, CGI Group Inc. As of September, 1998, CGI Group continued to operate the one remaining Multics system.

In 1969, the Multics name (pronounced MUHL-tihx) inspired the creators of a newer operating system to call it Unix.

This was last updated in November 2005

Continue Reading About Multics (Multiplexed Information and Computing Service)

Start the conversation

Send me notifications when other members comment.

By submitting you agree to receive email from TechTarget and its partners. If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. Privacy

Please create a username to comment.


File Extensions and File Formats

Powered by:


  • risk map (risk heat map)

    A risk map, also known as a risk heat map, is a data visualization tool for communicating specific risks an organization faces.

  • internal audit (IA)

    An internal audit (IA) is an organizational initiative to monitor and analyze its own business operations in order to determine ...

  • pure risk (absolute risk)

    Pure risk, also called absolute risk, is a category of threat that is beyond human control and has only one possible outcome if ...


  • federated identity management (FIM)

    Federated identity management (FIM) is an arrangement that can be made among multiple enterprises to let subscribers use the same...

  • cross-site scripting (XSS)

    Cross-site scripting (XSS) is a type of injection security attack in which an attacker injects data, such as a malicious script, ...

  • firewall

    In computing, a firewall is software or firmware that enforces a set of rules about what data packets will be allowed to enter or...



  • business continuity and disaster recovery (BCDR)

    Business continuity and disaster recovery (BCDR) are closely related practices that describe an organization's preparation for ...

  • business continuity plan (BCP)

    A business continuity plan (BCP) is a document that consists of the critical information an organization needs to continue ...

  • call tree

    A call tree -- sometimes referred to as a phone tree -- is a telecommunications chain for notifying specific individuals of an ...


  • volume manager

    A volume manager is software within an operating system (OS) that controls capacity allocation for storage arrays.

  • external storage device

    An external storage device, also referred to as auxiliary storage and secondary storage, is a device that contains all the ...

  • NetApp SolidFire

    NetApp SolidFire is a business division of NetApp Inc. that specializes in all-flash storage systems.


  • hybrid hard disk drive (HDD)

    A hybrid hard disk drive is an electromechanical spinning hard disk that contains some amount of NAND Flash memory.