Editing Operating system

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In [[Personal computer|computing]], an '''''operating system''''' (often abbreviated '''OS''') is the system [[software]] responsible for the direct control and management of [[Personal computer|hardware]] and basic system operations. It also provides a foundation upon which to run application software such as word processing programs, web browsers and [[computer game]]s.

==History==
In April 1974,<ref name="katz">Michael Katz, Robert Levering, Milton Moskowitz (1985), ''Computer Entrepreneur'', page 469, [[Wikipedia:Penguin Group|Penguin Group]]</ref> Japanese company [[Wikipedia:Sord Computer Corporation|Sord]] introduced the SMP80/x series of [[Personal computer|microcomputers]].<ref name="ipsj">http://museum.ipsj.or.jp/en/computer/personal/0086.html</ref> The SMP80/x series were the first microcomputers with an operating system,<ref>Michael Katz, Robert Levering, Milton Moskowitz (1985), ''Computer Entrepreneur'', page 463, Penguin Group</ref> and marked a major leap toward the popularization of microcomputers.<ref name="ipsj"/>

===Modern operating systems===
As of 2005, the major operating systems in widespread use on general-purpose computers (including [[personal computer]]s) have consolidated into two main families: the [[Unix-like]] family and the [[Microsoft Windows]] family. [[Mainframe]] computers and [[embedded system]]s use a variety of different operating systems, many with no direct connection to Windows or Unix.

The ''[[Unix-like]]'' family is a more diverse group of operating systems, with several major sub-categories including [[System V]], [[BSD]], and [[Linux]]. The name "Unix" is a trademark of [[The Open Group]] which licenses it for use to any operating system that has been shown to conform to the definitions that they have cooperatively developed. The name is commonly used to refer to the large set of operating systems which resemble the original Unix. Unix systems run on a wide variety of machine architectures. Unix systems are used heavily as [[server]] systems in business, as well as [[workstation]]s in academic and engineering environments. [[Free software]] Unix variants, such as [[Linux]] and [[BSD]] are increasingly popular, and have made inroads on the desktop market as well. Some proprietary Unix variants like HP's [[HP-UX]] and IBM's [[AIX]] are designed to run only on that vendor's proprietary hardware while others can run on the vendor's proprietary hardware and also on industry-standard PCs. Sun's formerly proprietary [[Solaris Operating Environment|Solaris]] (it is becoming open-source under the CDDL license) is one such versatile but true Unix (it can run on Sun's servers but also on smaller x86 systems). Apple's [[Mac OS X]] (now called [[macOS]], a BSD variant, replaced Apple's earlier (non-Unix) [[Mac OS]] in a small but dedicated market, becoming one of the most popular Unix-like systems in the process.

The ''[[Microsoft Windows]]'' family of operating systems originated as a graphical layer on top of the older [[MS-DOS]] environment for the [[IBM PC]]. Modern versions are based on the newer [[Windows NT]] core that first took shape in [[OS/2]]. Windows runs on 32- and 64-bit [[Intel]] and [[AMD]] computers, although earlier versions also ran on the [[DEC Alpha]], [[MIPS]] and [[PowerPC]] architectures (and there was work in progress to make it work also on the [[SPARC]] architecture). Today, Windows is a popular desktop operating system, enjoying a near-[[monopoly]] of around 90% of the worldwide desktop [[market share]]. It is also widely used on low-end and mid-range servers, supporting applications such as [[Web server]]s and [[Wikipedia:DBMS|database servers]].

==Common operating systems==
* [[Mac OS X]] / [[macOS]]
* [[Microsoft Windows]]
* [[DOS]] / [[MS-DOS]]
* [[GNU/Linux]]
* [[:Category:Operating systems|More operating systems]]

==References==
{{Reflist}}

==External Links==
* [http://dmoz.org/Computers/Software/Operating_Systems/ Operating system @ dmoz.org]
* [http://cliki.tunes.org TUNES wiki, contains reviews of operating systems]
* [http://www.cbi.umn.edu/iterations/haigh.html Multicians.org and the History of Operating Systems]
* [http://www.elook.org/computing/operating-system.htm Operating System - explains what an operating system is and provides various examples]
* [http://mega-tokyo.com/osfaq2/ The "Write Your Own Operating System" OS Developer FAQ]
* [http://computer.howstuffworks.com/operating-system.htm How OSs Work]
* [http://www.groovyweb.uklinux.net/index.php?page_name=Operating%20system%20programming Operating System Programming- Tutorials and source code]
* [http://www.osdata.com Operating Systems Technical Comparison]
* [http://www.osdever.net/ BonaFide OS Development] - resource for operating system developers