Xenix is a discontinued version of the

Unix Unix (; trademarked as UNIX) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, and ot ...

operating system An operating system (OS) is system software that manages computer hardware, software resources, and provides common services for computer programs. Time-sharing operating systems schedule tasks for efficient use of the system and may also in ...

for various

microcomputer A microcomputer is a small, relatively inexpensive computer having a central processing unit (CPU) made out of a microprocessor. The computer also includes memory and input/output (I/O) circuitry together mounted on a printed circuit board (PC ...

platforms, licensed by

Microsoft Microsoft Corporation is an American multinational technology corporation producing computer software, consumer electronics, personal computers, and related services headquartered at the Microsoft Redmond campus located in Redmond, Washing ...

from

AT&T Corporation AT&T Corporation, originally the American Telephone and Telegraph Company, is the subsidiary of AT&T Inc. that provides voice, video, data, and Internet telecommunications and professional services to businesses, consumers, and government agen ...

in the late 1970s. The

Santa Cruz Operation The Santa Cruz Operation, Inc. (usually known as SCO, pronounced either as individual letters or as a word) was an American software company, based in Santa Cruz, California, that was best known for selling three Unix operating system variants ...

(SCO) later acquired exclusive rights to the software, and eventually replaced it with SCO UNIX (now known as

SCO OpenServer Xinuos OpenServer, previously SCO UNIX and SCO Open Desktop (SCO ODT), is a closed source computer operating system developed by Santa Cruz Operation (SCO), later acquired by SCO Group, and now owned by Xinuos. Early versions of OpenServer were ...

). In the mid-to-late 1980s, Xenix was the most common Unix variant, measured according to the number of machines on which it was installed. Microsoft chairman

Bill Gates William Henry Gates III (born October 28, 1955) is an American business magnate and philanthropist. He is a co-founder of Microsoft, along with his late childhood friend Paul Allen. During his career at Microsoft, Gates held the positions ...

said at

Unix Expo Unix Expo was a conference and trade show that focused on the Unix operating system, and software based on Unix, in the information technology sector. It ran from 1984 through 1996 and was held in New York City during the autumn season. The show ...

in 1996 that, for a long time, Microsoft had the highest-volume AT&T Unix license.

History

Bell Labs Nokia Bell Labs, originally named Bell Telephone Laboratories (1925–1984), then AT&T Bell Laboratories (1984–1996) and Bell Labs Innovations (1996–2007), is an American industrial research and scientific development company owned by mult ...

, the developer of Unix, was part of the regulated

Bell System The Bell System was a system of telecommunication companies, led by the Bell Telephone Company and later by the American Telephone and Telegraph Company (AT&T), that dominated the telephone services industry in North America for over one hundr ...

and could not sell Unix directly to most end users (academic and research institutions excepted); it could, however, license it to software vendors who would then resell it to end users (or their own resellers), combined with their own added features. Microsoft, which expected that Unix would be its operating system of the future when personal computers became powerful enough, purchased a license for Version 7 Unix from AT&T in 1978, and announced on August 25, 1980, that it would make the software available for the

16-bit 16-bit microcomputers are microcomputers that use 16-bit microprocessors. A 16-bit register can store 216 different values. The range of integer values that can be stored in 16 bits depends on the integer representation used. With the two mos ...

microcomputer market. Because Microsoft was not able to license the "Unix" name itself, the company gave it an original name. Microsoft called Xenix "a universal operating environment". It did not sell Xenix directly to end users, but licensed the software to OEMs such as IBM, Intel, Management Systems Development, Tandy, Altos Computer, SCO, and Siemens (

SINIX Sinix may refer to: * SINIX, computer operating system * Şınıx, Azerbaijan {{dab