Usage share of operating systems

Usage share of web client operating systems. (Source: Median values from Usage share of operating systems for August 2011.)

  Windows XP (35.21%)

  Windows 7 (31.21%)

  Windows Vista (11.27%)

  Mac OS X (7.31%)

  iOS (3.38%)

  Android (1.30%)

  Linux (1.11%)

Different categories of computers use a wide variety of operating systems, and the usage share varies enormously from one category to another.

In some categories a single family of operating systems is dominant. For example, most desktop and laptop computers use Microsoft Windows and most supercomputers use Linux. In other categories, such as smartphones and servers, there is greater diversity and competition.

Information about operating system share is difficult to obtain. In most of the categories below, there is no reliable primary source or methodology for its collection.

Desktop and laptop computers

There is little openly published information on the usage share of desktop and laptop computers. Gartner publishes estimates, but the way the estimates are calculated is not openly published. Also, sales may overstate usage. Most computers are sold with a pre-installed OS; some users replace that OS with a different one due to personal preference. Conversely, sales underestimate usage, by not counting pirated copies. For example, in 2009, "U.S. research firm IDC estimated that 80% of software sold in China last year was pirated." (Windows was mentioned, but no specific estimate for Windows was given.)^[1] As another example, in 2007, the automated push of IE7 update onto legal copies of Windows, contrasted with web browser share statistics, led one author to "estimate that 25%–35% of all Windows XP machines are illegal".^[2]

Estimates for 2011

These are current-year sales estimates, not accumulative usage share for all PCs that are in use.

In August 2011, Gartner estimated Apple's PC market share in US as 10.7% for Q2 2011. Apple's worldwide market share is not listed, because not in top 5; inferred to be 5% or below. Gartner's numbers include netbooks, but not media tablets such as the iPad. Total units in Q2 2011 from all vendors, ~85 million.^[3]

"A Gartner forecast calls for Mac OS to ship on 4.5 percent of new PCs worldwide in 2011 and 5.2 percent in 2015. Gartner does not expect Google Chrome OS, Google Android or HP's webOS to get 'any significant market share' on PCs in the next few years, and expects Linux operating systems to remain at less than 2 percent share over the next several years."^[4]

Apple reports selling 4 million Macs in Q2 2011, the third quarter in Apple's fiscal year.^[5]

Older information

In a speech to investors in February 2009, Steve Ballmer of Microsoft presented a slide based on Microsoft's research; while it showed no figures, the pie chart depicted Linux and Apple as each having roughly 5–6% of home and business PCs.^[6]

Web client usage share (see below) is often used as a proxy for desktop share, but many desktops are not used for web access so do not get counted in these figures. The correlation between desktop share and web client share is also being challenged by mobile web access, which rose through 1% in 2009 and 4% in 2010.^[7]

Microsoft's CFO Peter Klein stated in July 2010 that Windows 7 now runs on more than 15% of all PCs worldwide.^[8] A Forrester Research study of desktop operating systems used in North American and European companies in 2010 found Windows 7 on 10% of all commercial desktops, Windows XP on 75% and Vista on 7%.^[9]

In October 2010 Tim Cook of Apple claimed that 1 in 5 of desktop/laptop computers sold in the United States is a Mac.^[10]

Web clients

The following information on web clients is obtained from the User agent information supplied to web servers by web browsers. This is an inexact science for a variety of reasons. For a discussion on the shortcomings see Usage share of web browsers.

The most recent data from various sources published during the last six months is summarized in the table below. (All of these sources monitor a substantial number of web sites. Statistics that relate to a single web site are excluded.)

Source	Date	Microsoft Windows				Apple		Linux kernel based		Symbian	Black- Berry OS	Other
		7	Vista	XP	All versions	Mac OS X	iOS	GNU Linux	Android
AT Internet[11]	Aug. 2011	33.0%	14.7%	38.4%	87.1%	6.7%	3.7%	1.0%	0.9%	—	—	0.6%
Clicky Web Analytics[12]	Oct. 2011	33.67%	10.17%	26.11%	79.53%	13.25%	3.81%	1.16%	1.77%	0.12%	0.32%	0.04%
Chitika[13]	Oct. 2011	—	—	—	77.2%	10.2%	5.4%	2.9%	3.3%	—	—	1.0%
Net Market Share[14][15]	Oct. 2011	32.60%	8.33%	45.23%	86.49%	6.54%	3.40%	1.12%	1.04%	0.19%	0.14%	1.08%
StatCounter Global Stats[16][17][18]	Oct. 2011	37.85%	10.45%	35.93%	84.57%	6.71%	2.58%	0.79%	1.58%	1.95%	0.63%	1.19%
StatOwl[19]	Oct. 2011	33.24%	12.91%	33.20%	78.94%	14.04%	—	0.70%	—	—	—	6.32%
W3Counter[20]	Oct. 2011	36.36%	9.57%	34.18%	80.21%	8.86%	3.21%	1.65%	1.29%	0.16%	0.60%	4.02%
Webmasterpro[21]	Nov. 2011	38.3%	14.1%	32.1%	85.8%	6.3%	4.4%	1.4%	1.6%	0.2%	0.02%	0.28%
Wikimedia[22]	Oct. 2011	34.18%	10.75%	32.8%	78.38%	8.41%	5.11%	1.53%	1.95%	0.15%	0.54%	3.93%
Median[original research?]	Oct. 2011	33.93%	10.60%	33.69%	80.21%	8.41%	3.76%	1.16%	1.59%	0.17%	0.43%	1.08%
Notes: The 'Other' column is obtained by summing Windows 'all versions' through BlackBerry OS and subtracting from 100%. ('Other' may be quite different between different sources. If a source does not show a value for a given OS, that OS is included in the source's 'Other' column.) AT Internet measures 23 European countries. Clicky Web Analytics does not publish desktop/mobile split so mean of Net Market Share and StatCounter figures (6.035% mobile) used in lieu[improper synthesis?]. Figures are averages over last 7 days of month. StatOwl measures desktop share and predominantly US web sites with "broad appeal".[23] Figure for XP includes Server 2003. Figures reduces by 6.035% (see above) to allow for missing mobile usage[improper synthesis?]. W3Counter shows only the top ten operating systems and is based on the last 15,000 page views to each of over 50,000 web sites tracked. Webmasterpro samples over 100,000 predominantly German-language sites. Figures are seven-day averages over period Nov 9-15. Wikimedia uses 1:1000 sampling of its logs when deriving the usage numbers. Figure for Vista includes Server 2008; XP includes Server 2003. iOS figures include iPhone, iPod and iPad. Mac OS X is broken down by four of the sources listed above and all of them show that version 10.6 (Snow Leopard) is the most widely used.

Netbooks

The netbook market has been dominated by Microsoft Windows, with Linux in second place.

Initially, Linux dominated the netbook market when Asus started it with the Eee PC in October 2007, but this lead did not last long. Asus and Acer, which accounted for 90% of the early netbook market, installed Linux on 30% of their machines.^[24]

Microsoft responded by extending the life of Windows XP. By February 2009, Microsoft cited data from NPD Retail Tracking Service which showed that US market share of Windows on netbooks went from under 10% to 96%.^[25]

In November 2009, an analyst at ABI said that of the 35 million netbooks to ship globally in 2009, 68% would have Windows and 32% Linux.^[26]

According to DisplaySearch, netbooks and tablets rose from just under a 14% share of the overall portable computer market in third quarter of 2008 to around 20% in the second quarter of 2009, and remained at around 20% until the middle of 2010. During 2010, Apple's iPad tablet computer gained a 6.5% share of this market sector in the first quarter and DisplaySearch forecast this will rise to 30% in the second.^[27]

Tablet computers

Tablet computers, or simply tablets, became a significant OS market share category starting with Apple's iOS-based iPad in 2010. ~ 29 million iPads sold to date, as of June 2011.

2011 Sales and Estimates (millions of units):

iOS: Q1: 7.3, Q2: 4.7 (limited by supply shortages)^[28]

Android: "Android media tablets have collectively taken 20% market share away from the iPad in the last 12 months."^[29]

"Apple is set to increase its iPad shipments at a faster rate than previously expected in 2011 and beyond, causing the global media tablet market to exceed growth expectations during the next few years, according to data from information and analysis provider IHS. Apple will ship 44 million iPads in 2011; shipments expected to reach 120 million units in 2015. Apple is expected to account for 74 percent of media tablet shipments in 2011 and 43-44 percent in 2015."^[30]

Top vendors: In Q1 2011, Apple's iOS sold 7.3 million tablets. (Q2 number not used, because was limited by supply shortages.) Google's Android shipped on 1 - 2 million tablets per quarter (20% estimate by ABI).

Mobile devices

Share of worldwide 2011 Q2 smartphone sales to end users by operating system, according to Gartner.^[31]

Mobile operating systems that can be found on smartphones include Nokia's Symbian, Apple's iOS, RIM's BlackBerry, Microsoft's Windows Mobile (marketed as Windows Phone) and its successor Windows Phone 7, Google's Android, Samsung's Bada, and HP's webOS. Android and webOS are in turn built on top of Linux, and iOS is derived from the BSD and NeXTSTEP operating systems. Linux, BSD, and NeXTSTEP are all related to Unix.

Gartner's Q2 2011 unit numbers total 107 million with Google's Android shipping on 47 million smartphones, Nokia's Symbian on 24 million and Apple's iOS on 20 million.^[31]

Canalys' Q2 2011 unit numbers total 108 million with Google's Android shipping on 52 million smartphones, Apple's iOS on 20 million, and Nokia's Symbian on < 20 million.^[32] Nokia confirms its Q2 smartphone sales were 16.7 million units.^[33][34]

Total unit predictions for 2011: (IDC) 472 million;^[35] (Gartner) 468 million.^[36]

Predictions for 2012: (Gartner): 630 million units; Android 49% / iOS 19% / BlackBerry 13% / Windows 11% / Symbian 5% / Other 3%.^[36] (Taiwan/Market Intelligence Center): Android 40% / iOS 19% / Windows 17% / Other 24%.^[37] (IDC) 582 million units total.^[38]

Predictions for 2015: (Gartner): 1105 million units; Android 49% / Windows 20% / iOS 17% / BlackBerry 11% / Other 3%.^[36] (IDC): 982 million units; Android 44% / Windows 20% / iOS 17% / BlackBerry 13% / Other 6%.^[35]

Source	Date	Symbian	BlackBerry	iOS	Android	Bada	Windows	Other
Gartner[31]	Q2 2011	22.1%	11.7%	18.2%	43.4%	1.9%	1.6%	1.0%
Gartner[36]	2011 forecast	19.2%	13.4%	19.4%	38.5%	*	5.6%	3.9%
IDC[35]	2011 forecast	20.6%	14.2%	18.2%	38.9%	*	3.8%	4.3%
Taiwan/MIC[37]	2011 forecast	23%	*	18%	38%	*	*	21%
Canalys[32]	Q2 2011	**	**	19%	48%	**	1%	**
Canalys[39]	Q4 2010	31.0%	14.6%	16.2%	33.3%	*	3.1%	3.0%
Stat Counter[40]	August 2011	32.12%	11.84%	19.41%	20.6%	0.45%
Wikimedia[22]	August 2011	2.16%	6.91%	67.09%	22.94%		0.90%
NPD Group (US only)[41]	Q2 2011		11%	29%	52%
Canalys (US only)[42]	Q3 2010		24.2%	26.2%	43.6%		3.0%
Millennial Media (US only)[43][44]	August 2011	1%	13%	28%	54%	*	1%	3%
Nielsen Company (US only)[45]	Q2 2011	2%	20%	28%	39%		9%
Comscore (US only)[46]	August 2011	1.8%	19.7%	27.3%	43.7%		5.7%
Notes: The above table is share of smartphone OSs - not overall marketshare. StatCounter measures share of mobile web browsing Millennial Media measures share of ad impressions (*) Included in "Other". (**) Source numbers are per device vendor; breakdown by OS is incomplete.

Servers

Server market share can be measured with statistical surveys of publicly accessible servers, such as web servers, mail servers^[47] or DNS servers on the Internet: the operating system powering such servers is found by inspecting raw response messages. This method gives a good insight into market share of operating systems actually installed on those servers, however it only includes servers publicly accessible on Internet.

Source	Date	Method	Unix/Unix like				Microsoft Windows	References
			All	Linux	BSD	Solaris
W3Techs	August 2011	Units (Web)	63.90%				36.10%	[48][49]
Security Space	August 2009	Units (Web)		>60.00%				[50][51]
Notes: W3Techs survey in August 2011 checked the top 1 million Web servers (according to Alexa). Security Space survey in August 2009 checked 38,549,333 publicly accessible Web servers. Netcraft SSL survey[52] in January 2009 also checked 1,014,301 publicly accessible Web servers, but the survey is only valid for SSL Web servers and it is not a good measure for our purpose.

Another method is to measure server hardware sold through commercial channels - market share by units sold or market share by revenue. However these methods undercount the share of open source operating systems currently in use, since such operating systems are usually obtained for free with or without a support plan.^{[unbalanced opinion][citation needed]}

Source	Date	Method	Microsoft Windows	Unix/Unix like		References
				All	Linux
IDC	Q1 2011	Revenue	48.5%	38.7%	16.9%	[53]
Gartner	2007	Revenue	66.8%	30.0%	23.2%	[54][55]

Mainframes

IBM System z has a 90-95% share of the mainframe computer hardware market.^[56]

Operating systems for IBM System z generation hardware include IBM's bundled proprietary z/OS,^[56] Linux on System z and as at October 7, 2008; 3 years ago (2008-10-07) the prototype OpenSolaris for System z.

Gartner reported on December 23, 2008; 2 years ago (2008-12-23) that Linux on System z was used on approximately 28% of the "customer z base" and that they expected this to increase to over 50% in the following five years.^[57]

Of Linux on System z, Red Hat and Novell compete to sell RHEL and SLES respectively.

• Prior to 2006, Novell claimed a market share of 85% or more.
• Red Hat has since claimed 18.4% in 2007 and 37% in 2008.^[58]
• Gartner reported at the end of 2008 that Novell had an 80% share of mainframe Linux.^[57]

Supercomputers

Graph of supercomputer OS market share from around 1994 to 2010 according to TOP500.^[59]

The TOP500 project lists and ranks the 500 fastest supercomputers that benchmark results are submitted for. It then publishes the collected data twice a year. The June 2011 figures are below.

Source	Date	Linux	IBM AIX	Other Unix	Microsoft HPCS 2008	Other	References
TOP500	June 2011	91.2%	4.0%	0.4%	1.2%	3.0%.	[60][61]

See also

• Comparison of operating systems
• List of operating systems
• Timeline of operating systems

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