From Wikipedia, the free encyclopedia
Jump to: navigation, search
For other uses, see Theos (disambiguation).

THEOS, which translates from Greek as "God", is an operating system which started out as OASIS, a microcomputer operating system for small computers that use the Z80 processor. Originally written in the late 1970s by Timothy S. Williams as a low-cost alternative to the more expensive mini- and mainframe- computers that were popular in the day, OASIS provided time-sharing multiuser facilities to allow several users to utilise the resources of one computer. Similar in concept to MP/M or UNIX, THEOS uses external device drivers rather than a kernel, allowing it to be more portable to other environments, though support has been primarily directed towards industry-standard hardware (i.e. PC's). THEOS is specifically aimed at small business users, with a wide range of vertical-market applications packages being developed and supported by individuals and companies.

The languages distributed with THEOS include THEOS Multi-User Basic and C. A powerful EXEC shell language can be used for task automation or to produce a turnkey system.

When the operating system was launched for the IBM Personal Computer/AT in 1982, the decision was taken to change the name from OASIS to THEOS, short for THE Operating System.

A number of security features exist, including dynamic passwords (where the password includes part of the date or time, or client IP address, or other dynamic elements), allow/deny security, a comprehensive inbound and outbound firewall, and an option to require a certain level of encryption in the workstation connection. In addition, the object file format is proprietary, and the operating system uses Intel "protected mode" to further increase defence against buffer overrun attacks.

THEOS was introduced in Europe by Fujitsu and other hardware manufacturers 30 years ago, and is distributed by a number of distributors in Great Britain, Spain, Portugal, Germany, Italy and more. The 'current' version is THEOS Corona Commercial Release 6, which was released in December 2008, and a number of updates have been released since that time. The current Windows Workstation Client (as of May 2009) is version 3.16 from July 2003.


BYTE in 1985 stated that "the functionality of THEOS is somewhere between MS-DOS and UNIX". The magazine criticized the documentation's quality, and concluded that the price was too high compared to other multiuser operating systems for the PC such as Pick and Coherent.[1]

See also[edit]


  1. ^ Rochkind, Marc J. (Fall 1985). "Pick, Coherent, and THEOS". BYTE. p. 231. Retrieved 19 March 2016. 

External links[edit]