Internet Explorer

Internet Explorer

Internet Explorer 11 running on Windows 7
Original author(s)	Thomas Reardon
Developer(s)	Microsoft
Initial release	August 16, 1995 (1995-08-16)
Stable release	Windows: v11.0.9600.16476 (11.0.2) (10 December 2013 (2013-12-10)) [±] Mac: 5.2.3 (June 16, 2003 (2003-06-16)) [±] Unix: 5.01 SP1 (2001 (2001)) [±]
Development status	Windows: Active Mac: Discontinued Unix: Discontinued
Written in	C++[1]
Operating system	Windows, Mac OS X, Solaris OS, HP-UX
Included with	Windows 95 OSR1 and later Windows NT 4 and later Mac OS 8.1 through Mac OS X 10.2 Xbox 360 Xbox One
Engine	Trident v7.0, Chakra
Platform	IA-32, x64, ARMv7, IA-64, PowerPC, 68k, SPARC, PA-RISC
Available in	95 languages[2]
Type	Web browser Feed reader
License	Proprietary, requires a Windows license[3]
Website	microsoft.com/ie
Standard(s)	HTML5, CSS3, WOFF, SVG, RSS, Atom, JPEG XR
Internet Explorer versions: 1 · 2 · 3 · 4 · 5 · 6 · 7 · 8 · 9 · 10 · 11

Internet Explorer (formerly Microsoft Internet Explorer and Windows Internet Explorer, commonly abbreviated IE or MSIE) is a series of graphical web browsers developed by Microsoft and included as part of the Microsoft Windows line of operating systems, starting in 1995. It was first released as part of the add-on package Plus! for Windows 95 that year. Later versions were available as free downloads, or in service packs, and included in the OEM service releases of Windows 95 and later versions of Windows.

Internet Explorer is one of the most widely used web browsers, attaining a peak of about 95% usage share during 2002 and 2003.^[4] Its usage share has since declined with the launch of Firefox (2004) and Google Chrome (2008), as well as with the growing popularity of operating systems such as OS X, Linux and Android that do not run Internet Explorer. Estimates for Internet Explorer's overall market share range from 27.4% to 54.13%, as of October 2012 (browser market share is notoriously difficult to calculate). Microsoft spent over US$100 million per year on Internet Explorer in the late 1990s,^[5] with over 1000 people working on it by 1999.^[6]

Since its first release, Microsoft has added features and technologies such as basic table display (in version 1.5); XMLHttpRequest (in version 5), which aids creation of dynamic web pages; and Internationalized Domain Names (in version 7), which allow Web sites to have native-language addresses with non-Latin characters. The browser has also received scrutiny throughout its development for use of third-party technology (such as the source code of Spyglass Mosaic, used without royalty in early versions) and security and privacy vulnerabilities, and both the United States and the European Union have alleged that integration of Internet Explorer with Windows has been to the detriment of other browsers.

The latest stable release is Internet Explorer 11, with an interface allowing for use as both a desktop application, and as a Windows 8 application.

Versions of Internet Explorer for other operating systems have also been produced, including an Xbox 360 version called Internet Explorer for Xbox and an embedded OEM version called Pocket Internet Explorer, later rebranded Internet Explorer Mobile, which is currently based on Internet Explorer 9 and made for Windows Phone, Windows CE, and previously, based on Internet Explorer 7 for Windows Mobile. It remains in development alongside the desktop versions. Internet Explorer for Mac and Internet Explorer for UNIX (Solaris and HP-UX) have been discontinued.

History

The Internet Explorer project was started in the summer of 1994 by Thomas Reardon, who, according the Massachusetts Institute of Technology Review of 2003,^[7] used source code from Spyglass, Inc. Mosaic, which was an early commercial web browser with formal ties to the pioneering NCSA Mosaic browser.^[8][9] In late 1994, Microsoft licensed Spyglass Mosaic for a quarterly fee plus a percentage of Microsoft's non-Windows revenues for the software.^[9] Although bearing a name similar to NCSA Mosaic, Spyglass Mosaic had used the NCSA Mosaic source code sparingly.^[6] Microsoft was sued by Synet Inc. in 1996 over the trademark infringement.^[10]

Early versions

The first version of Internet Explorer, Microsoft Internet Explorer (later referred to as Internet Explorer 1) made its debut on 16 August 1995. It was a reworked version of Spyglass Mosaic, which Microsoft licensed from Spyglass Inc., like many other companies initiating browser development.^[8][9] It came with Microsoft Plus! for Windows 95 and the OEM release of Windows 95,^{[citation needed]} and was installed as part of the Internet Jumpstart Kit in Plus!.^[11] The Internet Explorer team began with about six people in early development.^[6][12] Internet Explorer 1.5 was released several months later for Windows NT and added support for basic table rendering. By including it free of charge on their operating system, they did not have to pay royalties to Spyglass Inc, resulting in a lawsuit and a US$8 million settlement on January 22, 1997.^[13][14]

Windows Internet Explorer 8

Windows Internet Explorer 8 was released on 19 March 2009. It had been in development since August 2007 at the latest.^[15] On 5 March 2008, the first public beta (Beta 1) was released to the general public.^[16] On 27 August 2008, the second public beta (Beta 2) was released.^[17] It is supported in Windows XP SP2 and SP3, Windows Server 2003 SP2, Windows Vista, Windows 7, and Windows Server 2008 on both 32-bit and 64-bit architectures.^[18] Internet Explorer 8 (IE8) RC1 was released on 26 January 2009. Internet Explorer 8 "Final" was released on March 19, 2009. Security, ease of use, and improvements in RSS, CSS, and Ajax support are Microsoft's priorities for IE8.^[19][20] It includes much stricter compliance with web standards, including a planned full Cascading Style Sheets 2.1 compliance for the release version.^[21] All of these changes allowed Internet Explorer 8 to pass the Acid2 test.^[22] However, to prevent compatibility issues, IE8 also includes the IE7 rendering behaviour. Sites that expect IE7 quirks can disable IE8's breaking changes by including a meta element in the HEAD section of the HTML document. IE8 also includes numerous improvements to JavaScript support as well as performance improvements,^[21] although it still does not pass the Acid3 test, with version 8.0 scoring 20/100.^[23] It includes support for accelerators, which allow supported web applications to be invoked without explicitly navigating to them; and WebSlices, which allows portions of a page to be subscribed to and monitored from a redesigned Favorites Bar.^[21] Other features include InPrivate privacy features and the SmartScreen Filter.^[24]

Windows Internet Explorer 9

Windows Internet Explorer 9 was released on 14 March 2011.^[25] Development for Internet Explorer 9 began shortly after the release of Internet Explorer 8.^[26] Microsoft first announced Internet Explorer 9 at PDC 2009, and spoke mainly about how it takes advantage of hardware acceleration in DirectX to improve the performance of web applications and quality of web typography. At MIX 10, Microsoft showed and publicly released the first Platform Preview for Internet Explorer 9, a frame for IE9's engine not containing any UI of the browser. Leading up to the release of the final browser, Microsoft released updated platform previews, each featuring improved JavaScript compiling (32-bit version), improved scores on the Acid3 test, as well as additional HTML5 standards support, approximately every 6 weeks. Ultimately, eight platform previews were released. The first public beta was released at a special event in San Francisco, which was themed around "the beauty of the web". The release candidate was released on February 10, 2011, and featured improved performance, refinements to the UI, and further standards support. The final version was released during the South by Southwest (SXSW) music and film festival in Austin, Texas, on 14 March 2011.^[25]

Internet Explorer 9 is only supported on Windows Vista SP2, Windows 7, and Windows Server 2008.^[27] It supports several CSS 3 properties (including border-radius, box-shadow, etc.), and embedded ICC v2 or v4 colour profiles support via Windows Color System. The 32-bit version has faster JavaScript performance, this being due to a new JavaScript engine called "Chakra".^[28] It also features hardware accelerated graphics rendering using Direct2D, hardware-accelerated text rendering using DirectWrite, hardware-accelerated video rendering using Media Foundation, imaging support provided by Windows Imaging Component, and high fidelity printing powered by the XPS print pipeline.^[29] IE9 also supports the HTML5 video and audio tags and the Web Open Font Format.^[30] Internet Explorer 9 initially scored 95/100 on the Acid3 test, but has scored 100/100 since the test was updated in September 2011.^[31]

Internet Explorer was to be omitted from Windows 7 and Windows Server 2008 R2 in Europe, but Microsoft ultimately included it, with a browser option screen allowing users to select any of several web browsers (including Internet Explorer).^{[32][33][34][35]}

Internet Explorer is now available on Xbox 360 with Kinect support, as of October 2012.^[36]

Internet Explorer 10

Internet Explorer 10 became generally available on October 26, 2012 alongside Windows 8 and Windows Server 2012. It became available for Windows 7 on February 26, 2013.^[37] Microsoft announced Internet Explorer 10 in April 2011 at MIX 11 in Las Vegas, releasing the first Platform Preview at the same time. At the show, it was said that Internet Explorer 10 was about 3 weeks in development.^[38] This release further improves upon standards support, including CSS3 gradients. Internet Explorer 10 drops support for Windows Vista and will only run on Windows 7 Service Pack 1 and later.^[39] Internet Explorer 10 Release Preview was also released on the Windows 8 Release Preview platform.

Internet Explorer 11

Internet Explorer 11 is featured in a Windows 8.1 update which was released on October 17, 2013. It includes an incomplete mechanism for syncing tabs. It is a major update to its developer tools,^[40][41] enhanced scaling for high DPI screens,^[42] HTML5 prerender and prefetch,^[43] HTML5 drag and drop, hardware-accelerated JPEG decoding,^[44] closed captioning, HTML5 full screen,^[45] and is the first Internet Explorer to support WebGL^[46][47][48] and Google's protocol SPDY (starting at v3).^[49]

Windows 8.1 only: cryptography (WebCrypto),^[40] adaptive bitrate streaming (Media Source Extensions),^[50] Encrypted Media Extensions.^[45]

Internet Explorer 11 was made available for Windows 7 users to download on November 7, 2013, with Automatic Updates in the following weeks.^[51]

Internet Explorer 11's user agent string now identifies the agent as "Trident" (the underlying layout engine) instead of "MSIE". It also announces compatibility with Gecko (the layout engine of Firefox). Neowin.net believes it is an attempt to suppress the IE-specific "CSS hacks" that do not work well with this version.^[52]

Microsoft claims that Internet Explorer 11, running the WebKit Sunspider JavaScript Benchmark, is the fastest browser as of 15 October 2013.^[53]

Features

Internet Explorer has been designed to view a broad range of web pages and provide certain features within the operating system, including Microsoft Update. During the heyday of the browser wars, Internet Explorer superseded Netscape only when it caught up technologically to support the progressive features of the time.^[54]

Standards support

Internet Explorer, using the Trident layout engine:

• Supports HTML 4.01, HTML 5, CSS Level 1, Level 2 and Level 3, XML 1.0, and DOM Level 1, with minor implementation gaps.
• Fully supports XSLT 1.0 as well as an obsolete Microsoft dialect of XSLT often referred to as WD-xsl, which was loosely based on the December 1998 W3C Working Draft of XSL. Support for XSLT 2.0 lies in the future: semi-official Microsoft bloggers have indicated that development is underway, but no dates have been announced.
• Almost full conformance to CSS 2.1 has been added in the Internet Explorer 8 release.^[55][56] The trident rendering engine in Internet Explorer 9 in 2011 scored highest of in the official W3C conformance test suite for CSS 2.1 of all major browsers.
• Supports XHTML in Internet Explorer 9 (Trident version 5.0). Prior versions can render XHTML documents authored with HTML compatibility principles and served with a text/html MIME-type.
• Supports a subset^[57] of SVG in Internet Explorer 9 (Trident version 5.0), excluding SMIL, SVG fonts and filters.

Internet Explorer uses DOCTYPE sniffing to choose between standards mode and a "quirks mode" in which it deliberately mimicks nonstandard behaviours of old versions of MSIE for HTML and CSS rendering on screen (Internet Explorer always uses standards mode for printing). It also provides its own dialect of ECMAScript called JScript.

Internet Explorer had been subjected to criticism by W3C over its limited support for SVG promoted by W3C.^[58]

Non-standard extensions

Internet Explorer has introduced an array of proprietary extensions to many of the standards, including HTML, CSS, and the DOM. This has resulted in a number of web pages that appear broken in standards-compliant web browsers and has introduced the need for a "quirks mode" to allow for rendering improper elements meant for Internet Explorer in these other browsers.

Internet Explorer has introduced a number of extensions to the DOM that have been adopted by other browsers. These include the innerHTML property, which provides access to the HTML string within an element^{[citation needed]} ; the XMLHttpRequest object, which allows the sending of HTTP request and receiving of HTTP response, and may be used to perform AJAX; and the designMode attribute of the contentDocument object, which enables rich text editing of HTML documents^{[citation needed]} . Some of these functionalities were not possible until the introduction of the W3C DOM methods. Its Ruby character extension to HTML is also accepted as a module in W3C XHTML 1.1, though it is not found in all versions of W3C HTML.

Microsoft submitted several other features of IE for consideration by the W3C for standardization. These include the 'behaviour' CSS property, which connects the HTML elements with JScript behaviours (known as HTML Components, HTC); HTML+TIME profile, which adds timing and media synchronization support to HTML documents (similar to the W3C XHTML+SMIL), and the VML vector graphics file format. However, all were rejected, at least in their original forms; VML was subsequently combined with PGML (proposed by Adobe and Sun), resulting in the W3C-approved SVG format, currently one of the few vector image formats being used on the web, which IE did not support until version 9.^[59]

Other non-standard behaviours include: support for vertical text, but in a syntax different from W3C CSS3 candidate recommendation, support for a variety of image effects^[60] and page transitions, which are not found in W3C CSS, support for obfuscated script code, in particular JScript.Encode.^[61] Support for embedding EOT fonts in web pages.^[62]

Favicon

Internet Explorer supports favicons in PNG, static GIF and native Windows icon formats. In Windows Vista and later, Internet Explorer can display native Windows icons that have embedded PNG files.^[63][64]

Usability and accessibility

Internet Explorer makes use of the accessibility framework provided in Windows. Internet Explorer is also a user interface for FTP, with operations similar to that of Windows Explorer. Pop-up blocking and tabbed browsing were added respectively in Internet Explorer 6 and Internet Explorer 7. Tabbed browsing can also be added to older versions by installing MSN Search Toolbar or Yahoo Toolbar.

Cache

Internet Explorer caches visited content in the Temporary Internet Files folder to allow quicker access (or offline access) to previously visited pages. The content is indexed in a database file, known as Index.dat. Multiple Index.dat files exist which index different content—visited content, web feeds, visited URLs, cookies, etc.^[65]

Prior to IE7, clearing the cache used to clear the index but the files themselves were not reliably removed, posing a potential security and privacy risk. In IE7 and later, when the cache is cleared, the cache files are more reliably removed, and the index.dat file is overwritten with null bytes.

Caching has been improved in IE9.^[66]

Group Policy

Internet Explorer is fully configurable using Group Policy. Administrators of Windows Server domains (for domain-joined computers) or the local computer can apply and enforce a variety of settings on computers that affect the user interface (such as disabling menu items and individual configuration options), as well as underlying security features such as downloading of files, zone configuration, per-site settings, ActiveX control behaviour and others. Policy settings can be configured for each user and for each machine. Internet Explorer also supports Integrated Windows Authentication.

Architecture

Internet Explorer uses a componentized architecture built on the Component Object Model (COM) technology. It consists of several major components, each of which is contained in a separate Dynamic-link library (DLL) and exposes a set of COM programming interfaces hosted by the Internet Explorer main executable, iexplore.exe:^[67]

• WinInet.dll is the protocol handler for HTTP, HTTPS and FTP. It handles all network communication over these protocols.
• URLMon.dll is responsible for MIME-type handling and download of web content, and provides a thread-safe wrapper around WinInet.dll and other protocol implementations.
• MSHTML.dll houses the Trident rendering engine introduced in Internet Explorer 4, which is responsible for displaying the pages on-screen and handling the Document Object Model of the web pages. MSHTML.dll parses the HTML/CSS file and creates the internal DOM tree representation of it. It also exposes a set of APIs for runtime inspection and modification of the DOM tree. The DOM tree is further processed by a layout engine which then renders the internal representation on screen.
• IEFrame.dll contains the user interface and window of IE in Internet Explorer 7 and above.
• ShDocVw.dll provides the navigation, local caching and history functionalities for the browser.
• BrowseUI.dll is responsible for rendering the browser user interface such as menus and toolbars.^[68]

Internet Explorer does not include any native scripting functionality. Rather, MSHTML.dll exposes an API that permit a programmer to develop a scripting environment to be plugged-in and to access the DOM tree. Internet Explorer 8 includes the bindings for the Active Scripting engine, which is a part of Microsoft Windows and allows any language implemented as an Active Scripting module to be used for client-side scripting. By default, only the JScript and VBScript modules are provided; third party implementations like ScreamingMonkey (for ECMAScript 4 support) can also be used. Microsoft also makes available the Microsoft Silverlight runtime (not supported in Windows RT) that allows CLI languages, including DLR-based dynamic languages like IronPython and IronRuby, to be used for client-side scripting.

Internet Explorer 8 introduces some major architectural changes, called Loosely Coupled IE (LCIE). LCIE separates the main window process (frame process) from the processes hosting the different web applications in different tabs (tab processes). A frame process can create multiple tab processes, each of which can be of a different integrity level; each tab process can host multiple web sites. The processes use asynchronous Inter-Process Communication to synchronize themselves. Generally, there will be a single frame process for all web sites. In Windows Vista with Protected Mode turned on, however, opening privileged content (such as local HTML pages) will create a new tab process as it will not be constrained by Protected Mode.^[69]

Extensibility

Internet Explorer exposes a set of Component Object Model (COM) interfaces that allow other components to extend the functionality of the browser.^[67] Extensibility is divided into two types: Browser extensibility and Content extensibility. The browser extensibility interfaces can be used to plug in components to add context menu entries, toolbars, menu items or Browser Helper Objects (BHO). BHOs are used to extend the feature set of the browser, whereas the other extensibility options are used to expose the feature in the UI. Content extensibility interfaces are used by different content-type handlers to add support for non-native content formats.^[67] BHOs not only have unrestricted access to the Internet Explorer DOM and event model, they also can access the filesystem, registry and other OS components. Content extensibility can be either in terms of Active Documents (Doc Objects) (e.g., SVG or MathML) or ActiveX controls.^[67] ActiveX is not supported in Windows RT. ActiveX controls are used for content handlers that render content embedded within an HTML page (e.g., Adobe Flash or Microsoft Silverlight, both not supported in Windows RT). Doc objects are used when the content type will not be embedded in HTML (e.g., Microsoft Word, PDF or XPS). In fact, the Trident rendering engine is itself exposed as a Doc object, so HTML in itself is treated as an Active Document.^[67]

Internet Explorer add-on components run with the same privileges as the browser itself, unlike client-side scripts that have a very limited set of privileges. Add-ons can be installed either locally, or directly by a web site. Since the add-ons have a more privileged access to the system, malicious add-ons can and have been used to compromise the security of the system. Internet Explorer 6 Service Pack 2 onwards provide various safeguards against this, including an Add-on Manager for controlling ActiveX controls and Browser Helper Objects and a "No Add-Ons" mode of operation as well as greater restrictions on sites installing add-ons.

Internet Explorer 9 introduced a new component — Add-on Performance Advisor. Add-on Performance Advisor shows a notification when one or more of installed add-ons exceed a pre-set performance threshold. The notification appears in the Notification Bar when the user launches the browser.

Internet Explorer itself can be hosted by other applications via a set of COM interfaces. This can be used to embed the browser functionality inside the application. Also, the hosting application can choose to host only the MSHTML.dll rendering engine, rather than the entire browser.^[67]

Security

Internet Explorer uses a zone-based security framework that groups sites based on certain conditions, including whether it is an Internet- or intranet-based site as well as a user-editable whitelist. Security restrictions are applied per zone; all the sites in a zone are subject to the restrictions.

Internet Explorer 6 SP2 onwards uses the Attachment Execution Service of Microsoft Windows to mark executable files downloaded from the Internet as being potentially unsafe. Accessing files marked as such will prompt the user to make an explicit trust decision to execute the file, as executables originating from the Internet can be potentially unsafe. This helps in preventing accidental installation of malware.

Internet Explorer 7 introduced the phishing filter, that restricts access to phishing sites unless the user overrides the decision. With version 8, it also blocks access to sites known to host malware. Downloads are also checked to see if they are known to be malware-infected.

In Windows Vista, Internet Explorer by default runs in what is called Protected Mode, where the privileges of the browser itself are severely restricted—it cannot make any system-wide changes. One can optionally turn this mode off but this is not recommended. This also effectively restricts the privileges of any add-ons. As a result, even if the browser or any add-on is compromised, the damage the security breach can cause is limited.

Patches and updates to the browser are released periodically and made available through the Windows Update service, as well as through Automatic Updates. Although security patches continue to be released for a range of platforms, most feature additions and security infrastructure improvements are only made available on operating systems which are in Microsoft's mainstream support phase.

On December 16, 2008, Trend Micro recommended users switch to rival browsers until an emergency IE patch was released to fix a potential security risk which "could allow outside users to take control of a person's computer and steal their passwords". Microsoft representatives countered this recommendation, claiming that "0.02% of internet sites" were affected by the flaw.

On December 17, 2008, a fix to the security problem above became available, with the release of the Security Update for Internet Explorer KB960714, which is available from Microsoft Windows Update's webpage. Microsoft has said that this update fixes the security risk found by Trend Micro the previous day.^[70][71]

In 2011, a report by Accuvant, funded by Google, rated the security (based on sandboxing) of Internet Explorer worse than Google Chrome but better than Mozilla Firefox.^[72][73]

Security vulnerabilities

Internet Explorer has been subjected to many security vulnerabilities and concerns: Much of the spyware, adware, and computer viruses across the Internet are made possible by exploitable bugs and flaws in the security architecture of Internet Explorer, sometimes requiring nothing more than viewing of a malicious web page in order to install themselves. This is known as a "drive-by install". There are also attempts to trick the user into installing malicious software by misrepresenting the software's true purpose in the description section of an ActiveX security alert.

A number of security flaws affecting IE originated not in the browser itself, but ActiveX-based add-ons used by it. Because the add-ons have the same privilege as IE, the flaws can be as critical as browser flaws. This has led to the ActiveX-based architecture being criticized for being fault-prone. By 2005, some experts maintained that the dangers of ActiveX have been overstated and there were safeguards in place.^[74] In 2006, new techniques using automated testing found more than a hundred vulnerabilities in standard Microsoft ActiveX components.^[75] Security features introduced in Internet Explorer 7 mitigated some of these vulnerabilities.

Internet Explorer in 2008 had a number of published security vulnerabilities. According to research done by security research firm Secunia, Microsoft did not respond as quickly as its competitors in fixing security holes and making patches available.^[76] The firm also reported 366 vulnerabilities in ActiveX controls, an increase from the prior year.

According to an October 2010 report in The Register, researcher Chris Evans had detected a known security vulnerability which, then dating back to 2008, had not been fixed for at least 600 days.^[77] Microsoft says that it had known about this vulnerability but it was of very low severity as the victim web site must be configured in a special way for this attack to be feasible at all.^[78]

In December 2010, researchers have been able to bypass the "Protected Mode" feature in Internet Explorer.^[79]

A security vulnerability exists in all versions of Internet Explorer higher than version 6, which allows the user's mouse cursor to be tracked by malicious display ads, even when Internet Explorer has been minimized. Microsoft has stated that it has no immediate plans to fix this vulnerability.^[80][81]

Vulnerability exploited in attacks on U.S. firms

In an advisory on January 14, 2010, Microsoft said that attackers targeting Google and other U.S. companies used software that exploits a security hole, which had already been patched, in Internet Explorer. The vulnerability affected Internet Explorer 6 on Windows XP and Server 2003, IE6 SP1 on Windows 2000 SP4, IE7 on Windows Vista, XP, Server 2008 and Server 2003, and IE8 on Windows 7, Vista, XP, Server 2003, and Server 2008 (R2).^[82]

The German government warned users against using Internet Explorer and recommended switching to an alternative web browser, due to the major security hole described above that was exploited in Internet Explorer.^[83] The Australian and French Government issued a similar warning a few days later.^[84][85] The first browser they recommended was Mozilla Firefox, followed by Google Chrome.^[86][87]

Market adoption and usage share

The adoption rate of Internet Explorer seems to be closely related to that of Microsoft Windows, as it is the default web browser that comes with Windows. Since the integration of Internet Explorer 2.0 with Windows 95 OSR 1 in 1996, and especially after version 4.0's release, the adoption was greatly accelerated: from below 20% in 1996 to about 40% in 1998 and over 80% in 2000.

Firefox 1.0 had surpassed Internet Explorer 5 in early 2005 with Firefox 1.0 at roughly 8 percent market share.^[88]

Approximate usage over time based on various usage share counters averaged for the year overall, or for the fourth quarter, or for the last month in the year depending on availability of reference.^{[89][90][91][92][93][94]}

According to StatCounter Internet Explorer's marketshare fell below 50% in September 2010.^[95] In May 2012 it was announced that Google Chrome overtook Internet Explorer as the most used browser worldwide.

Industry adoption

Browser Helper Objects are also used by many search engine companies and third parties for creating add-ons that access their services, such as search engine toolbars. Because of the use of COM, it is possible to embed web-browsing functionality in third-party applications. Hence, there are a number of Internet Explorer shells, and a number of content-centric applications like RealPlayer also use Internet Explorer's web browsing module for viewing web pages within the applications.

Removal

While a major upgrade of Internet Explorer can be uninstalled in a traditional way if the user has saved the original application files for installation, the matter of uninstalling the version of the browser that has shipped with an operating system remains a controversial one.

The idea of removing a stock install of Internet Explorer from a Windows system was proposed during the United States v. Microsoft case. One of Microsoft's arguments during the trial was that removing Internet Explorer from Windows may result in system instability. Indeed, programs that depend on libraries installed by IE, including Windows help and support system, fail to function without IE. Before Windows Vista, it was not possible to run Windows Update without IE because the service used ActiveX technology, which no other web browser supports.

Impersonation by malware

The popularity of Internet Explorer has led to the appearance of malware abusing its name. In January 28, 2011, a fake Internet Explorer browser calling itself "Internet Explorer – Emergency Mode" appeared along with the fake AVG antivirus and other fake antiviruses. It closely resembles the real Internet Explorer, but has fewer buttons and no search bar. If a user launches any other browser such as Google Chrome, Mozilla Firefox, Opera, Safari or the real Internet Explorer, this browser will pop-up instead. It also displays a fake error message, claiming that the computer is infected with malware and Internet Explorer has entered Emergency Mode. It blocks access to legitimate sites such as Google if infected users try to access them.^[96][97]

See also

• Windows Filtering Platform
• WinSock
• Month of bugs
• Web 2.0
• Web browser history
• Bing Bar

References

Further reading

External links

Wikimedia Commons has media related to Internet Explorer.

Wikinews has related news: France, Germany officials warn against using Internet Explorer

Wikibooks has a book on the topic of: Internet Explorer

• Official website
• IEBlog – MSDN Blogs—The weblog of the Internet Explorer team
• Internet Explorer Architecture
• Internet Explorer Community—The official Microsoft Internet Explorer Community
• Internet Explorer History
• IE Leak Patterns—Microsoft's analysis of how web pages can cause memory leaks in Internet Explorer, and how developers can prevent them.

v t e Internet Explorer Versions Main 1 2 3 4 5 6 7 8 9 10 11 Other Mobile for Mac for UNIX IEs4Linux Overview History Add-ons Box model Browser Helper Object (BHO) Easter eggs Extensions Removal Shells Technologies Accelerator ActiveX Dynamic HTML HTA HTML Components favicon.ico HTML+TIME Index.dat JScript MHTML MSXML RSS Platform Smart tags Temporary Internet Files Vector Markup Language Web Slice WPAD XHR/XDomainRequest Software & engines Administration Kit Developer Tools Integrated Windows Authentication Tasman Trident Chakra Implementations Active Channel Active Desktop ActiveMovie Channel Definition Format (.cdf) Comic Chat/Chat 2.0 DirectX Media Internet Mail and News Microsoft Java Virtual Machine (MSJVM) MSN Explorer MSN for Mac OS X NetMeeting NetShow Outlook Express Server Gated Cryptography (SGC) Spyglass Windows Address Book Windows Desktop Update Events First browser war Second browser war Download.ject Eolas v. Microsoft Sun v. Microsoft United States v. Microsoft Corp. People Tantek Çelik Dean Hachamovitch Scott Isaacs Inori Aizawa Category Commons Microsoft portal Internet portal

v t e Microsoft History All topics Board of directors Steve Ballmer Dina Dublon Bill Gates Maria Klawe Stephen J. Luczo David Marquardt Satya Nadella (CEO) Charles Noski Helmut Panke John W. Thompson (Chairman) Chief officers Satya Nadella (CEO) Amy Hood (CFO) Craig Mundie (CRSO) Kevin Turner (COO) Senior Leaders Tony Bates Lisa Brummel Julie Larson-Green Qi Lu Terry Myerson Mark Penn Tami Reller Harry Shum Presidents and VPs Joe Belfiore Jon DeVaan (SVP) Richard Rashid (SVP) S. Somasegar (SVP) Product families Operating systems Windows Windows Phone Software Office Servers Skype Visual Studio Hardware Xbox Surface Web properties MSN Bing Outlook.com SkyDrive MSDN TechNet Conferences Build MIX PDC TechEd WinHEC Criticism Bundling of Microsoft Windows iLoo Internet Explorer _NSAKEY Windows 9x 2000 ME XP Vista Xbox 360 Litigation Alcatel-Lucent v. Microsoft Apple v. Microsoft European Union Microsoft competition case Microsoft v. Lindows Microsoft vs. MikeRoweSoft Microsoft v. Shah United States v. Microsoft Acquisitions Altamira Software aQuantive Azyxxi Blue Ribbon Soundworks Bungie Calista Technologies Colloquis Connectix Consumers Software Danger Farecast FASA Studio Fast Search & Transfer Firefly Forethought GIANT Company Software Groove Networks Hotmail Jellyfish.com LinkExchange Lionhead Studios Massive Incorporated Onfolio PlaceWare Powerset ProClarity Rare ScreenTonic Skype Communications Teleo Tellme Networks Twisted Pixel Games Vermeer Technologies Visio Corporation VXtreme WebTV Networks Winternals Yammer Yupi Category Commons Microsoft portal

v t e Microsoft Windows components Management tools Backup and Restore Center Command Prompt Control Panel Applets Device Manager Disk Cleanup Disk Defragmenter Driver Verifier Event Viewer IExpress Management Console Netsh Problem Reports and Solutions Recovery Console Resource Monitor ScanDisk Sysprep System Configuration System File Checker System Policy Editor System Restore Task Manager Windows Easy Transfer Windows Installer Windows PowerShell Windows Update WinPE WinRE WinSAT WMI Applications Calculator Character Map Contacts DVD Maker Family Safety Fax and Scan Internet Explorer Journal Magnifier Media Center Media Player Mobile Device Center Mobility Center Narrator Notepad Paint Private Character Editor Remote Assistance Snipping Tool Sound Recorder Speech Recognition Store Tablet PC Input Panel Windows Desktop Gadgets Windows Photo Viewer Windows To Go WordPad Shell Aero AutoPlay AutoRun ClearType Explorer Search IFilter Saved search Namespace Special folder Start menu Taskbar Services Service Control Manager BITS CLFS Multimedia Class Scheduler Shadow Copy Task Scheduler Error Reporting Wireless Zero Configuration File systems CDFS DFS exFAT IFS FAT FAT12 FAT16 FAT32 NTFS Hard link Junction point Mount Point Reparse point Symbolic link TxF EFS ReFS UDF WinFS Server Domains Active Directory DNS Group Policy Roaming user profiles Folder redirection Distributed Transaction Coordinator MSMQ Windows Media Services Rights Management Services IIS Remote Desktop Services WSUS Windows SharePoint Services Network Access Protection PWS DFS Replication Remote Differential Compression Print Services for UNIX Remote Installation Services Windows Deployment Services System Resource Manager Hyper-V Architecture Architecture of Windows NT Vista startup Vista I/O CSRSS Desktop Window Manager DLL Enhanced Write Filter EXE File Protection Graphics Device Interface hal.dll I/O request packet Imaging Format Kernel Transaction Manager Library files Logical Disk Manager LSASS MinWin NTLDR Ntoskrnl.exe Object Manager Open XML Paper Specification Registry Resource Protection Security Accounts Manager Server Message Block Shadow Copy SMSS Startup process System Idle Process USER Win32 console Winlogon Security Action Center BitLocker Data Execution Prevention Kernel Patch Protection Mandatory Integrity Control Protected Media Path User Account Control User Interface Privilege Isolation Windows Defender Windows Firewall Compatibility COMMAND.COM Windows Services for UNIX POSIX subsystem Interix Virtual DOS machine Windows on Windows WoW64 API Active Scripting WSH VBScript JScript COM ActiveX ActiveX Document COM Structured storage DCOM OLE OLE Automation Transaction Server DirectX .NET Framework Windows Runtime Discontinued Computer games 3D Pinball Chess Titans FreeCell Hearts Hover! InkBall Hold 'Em Mahjong Titans Microsoft Minesweeper Purble Place Reversi Solitaire Spider Solitaire Tinker Others ActiveMovie Cardfile DriveSpace File Manager HyperTerminal Internet Mail and News Media Control Interface Microsoft Calendar Microsoft Diagnostics Microsoft Fax Microsoft WinHelp NTBackup Outlook Express Program Manager Video for Windows Windows Address Book Windows Calendar Windows File Protection Windows Mail Windows Messaging Windows Messenger Windows Movie Maker Microsoft NetMeeting Windows Photo Gallery Microsoft Write

v t e Gopher Active clients Free/open source Amaya Arachne Camino Classilla Conkeror ELinks Gnuzilla K-Meleon K-Ninja Kazehakase Line Mode Browser Lynx Songbird Mothra W3m xB Browser Proprietary Mosaic-CK OmniWeb Sleipnir VMS Mosaic Discontinued clients Agora Arena AT&T Pogo Beonex Communicator Cello Cyberjack Galeon IBrowse Internet Explorer for Mac Minimo Minuet Mosaic Mozilla Application Suite Netscape Browser Netscape Communicator Netscape Navigator 9 SlipKnot tkWWW UdiWWW Previously supported Epiphany Firefox Flock Internet Explorer SeaMonkey Server software Bucktooth PyGopherd Squid Persons Mark P. McCahill See also Gopher+ GopherVR Jughead Libwww Phlog SDF Public Access Unix System Veronica CCSO Nameserver Wide area information server

v t e News aggregators Client software Standalone Akregator BlogBridge BottomFeeder Cooliris FeedDemon Feedreader Feedly Flipboard Genieo Google Currents Liferea NetNewsWire News360 NewsAccess NewsBlur NewsFire Pulse RSS Bandit RSSOwl Sage Seesmic TweetDeck WebFetch Web browsers AOL Explorer Avant Browser Camino iCab Flock Internet Explorer K-Meleon Kazehakase Maxthon Firefox Netscape Browser Netscape Navigator 9 Opera OmniWeb Safari SeaMonkey Shiira Sleipnir Tencent Traveler Web Email clients Claws Mail Gnus IBM Lotus Notes Mail Microsoft Outlook Mozilla Thunderbird Netscape Messenger 9 Opera Mail Pegasus Mail The Bat! Windows Live Mail Zimbra Web-based software Bloglines CommaFeed Cheetah News Daylife Digg Reader Drupal Feedspot FriendFeed Google News Google Reader iGoogle dotCMS Imooty.eu Magnolia (CMS) My Yahoo! Newsknowledge Netvibes Pageflakes Planet Rojo.com Spokeo Tiny Tiny RSS WebGUI Windows Live Personalized Experience winnowTag Media aggregators Players Adobe Media Player Akregator Amarok Flock iTunes Juice MediaMonkey Miro Rhythmbox Songbird Winamp Zune RSS+BitTorrent BitLord BitTorrent 6 Deluge Miro Opera Mail qBittorrent Torrent Swapper TorrentFlux Tribler μTorrent Vuze ZipTorrent Related articles Comparison of feed aggregators RSS enclosure Italics indicate discontinued software.

v t e Timeline of web browsers   General Comparison History List for Unix Usage share   1990s 1990 WorldWideWeb (Nexus) 1991 Line Mode Browser libwww 1992 Erwise MacWWW (Samba) MidasWWW tkWWW ViolaWWW 1993 AMosaic Arena Cello Emacs/W3 Lynx 2 NCSA Mosaic VMS Mosaic 1994 AirMosaic Internet in a Box ANT Fresco Argo IBM WebExplorer MacWeb SlipKnot Minuet Navipress Mosaic/Mosaic Netscape/Netscape Navigator Spyglass Mosaic TCP/Connect II MacWeb 1995 Agora ALynx AMSD Ariadna Cyberjack eWorld Web Browser Grail Internet Explorer 1 Internet Explorer 2 Netscape Navigator 2 NetShark OmniWeb HotJava UdiWWW WebShark 1996 Cyberdog Arachne AWeb IBrowse Amaya Internet Explorer 3 Netscape Navigator 3 Opera 2 Oracle PowerBrowser tcpCONNECT4 Voyager 1997 Netscape Communicator Internet Explorer 4 Opera 3 1998 NeoPlanet Mozilla Application Suite 1999 iCab Internet Explorer 5   2000s 2000 Beonex Communicator Galeon K-Meleon MediaBrowser Netscape 6 Opera 4-5 2001 Internet Explorer 6 Opera 6 2002 Camino Epiphany Netscape (version 7) 2003 Maxthon Opera 7 Safari 2004 Phoenix/Firebird/Firefox 2005 AOL Explorer Deepnet Explorer Firefox 1.5 Opera 8 Safari 2 2006 Firefox 2 Internet Explorer 7 Opera 9 2007 Opera 9.5 Safari 3 2008 Google Chrome Firefox 3 2009 Google Chrome 2-3 Firefox 3.5 Internet Explorer 8 Opera 10 Safari 4   2010s 2010 Google Chrome 4-8 Firefox 3.6 Opera 11 Safari 5 2011 Google Chrome 9-16 Firefox 4 Firefox 5–9 Internet Explorer 9 Opera 12 2012 Google Chrome 17-23 Firefox 10–17 Internet Explorer 10 Safari 6 2013 Google Chrome 24-31 Firefox 18–26 Internet Explorer 11 Opera 15-18 Safari 7 2014 Google Chrome 32 Firefox 27 Opera 19   Related topics 3D Markup Language for Web Aliweb ARPANET ASCII BITNET Browser wars CompuServe Elm Email File Transfer Protocol Gopher HTML HyperCard HyTelnet NCSA Telnet NLS Prodigy Teletext Telnet Usenet UUCP Videotex Viewdata Virtual Reality Markup Language Web page Whole Internet User's Guide and Catalog World Wide Web X.25

v t e Web browsers Comparison History List for Unix Timeline Usage share Features Ad filtering Augmented browsing Bookmarks Bookmarklet Live bookmark Smart Bookmarks Browser extension Browser security Browser synchronizer comparison Cookies Download manager Favicon Incremental search Plug-in Privacy mode Tabs Universal Edit Button Web standards Acid tests Cascading Style Sheets HTML HTML5 JavaScript MathML OCSP SVG WebGL XHTML Related topics BrowserChoice.eu CRL HTTP HTTPS iLoo Internet suite Man-in-the-browser Mobile Web Offline reader PAC Pwn2Own Rich Internet application Site-specific browser SPDY SSL/TLS WebSocket Widget World Wide Web WPAD XML   Desktop WebKit-based Arora Avant Chromium Chrome Dragon Epic Opera SRWare Iron Torch Yandex.Browser Dooble Flock Fluid iCab Konqueror Lunascape Maxthon Midori OmniWeb Origyn Web Browser QupZilla rekonq Safari Shiira Sleipnir Uzbl Web WebPositive xombrero Trident-based AOL Explorer Avant Deepnet Explorer GreenBrowser Internet Explorer Lunascape Maxthon MediaBrowser MenuBox NeoPlanet NetCaptor Sleipnir SlimBrowser SpaceTime UltraBrowser WebbIE ZAC Browser Gecko-based AT&T Pogo Avant Camino Firefox Conkeror GNU IceCat IceDragon Pale Moon Pentadactyl Swiftfox Swiftweasel TenFourFox Timberwolf Vimperator xB Browser Galeon Ghostzilla K-Meleon Kazehakase Kirix Strata Lotus Symphony Lunascape Mozilla Beonex Communicator Classilla Netscape SeaMonkey Text-based ELinks Emacs/W3 Line Mode Browser Links Lynx Net-Tamer w3m Other abaco Amaya Arachne Arena Charon Dillo Gazelle IBM Home Page Reader IBrowse KidZui Mosaic Mothra NetPositive NetSurf   Mobile WebKit-based Android Browser BOLT Chrome Dolphin Browser Nintendo 3DS Internet Browser Rockmelt S60 web browser Safari Silk Steel Gecko-based Firefox for mobile MicroB Minimo Presto-based Nintendo DS & DSi Browser Opera Mini Opera Mobile Other BlackBerry Blazer Deepfish Galio ibisBrowser Internet Explorer Mobile Iris Browser Konqueror Embedded NetFront Obigo Browser Skweezer Skyfire Teashark ThunderHawk uZard Web Vision WinWAP   Television and video game console WebKit-based Google TV NetFront Steam overlay Wii U Internet Browser Gecko-based Kylo Presto-based Internet Channel Other Galio MSN TV (WebTV) Software no longer in development shown in italics Category Commons Internet portal Software portal