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Windows Internet Explorer

Version 7 running on Windows Vista.
Developed by	Microsoft
Initial release	August 1995
Latest release	7.0.5730.13 (Windows XP/Server 2003) 7.0.6001.18000 (Vista SP1/Server 2008)
Preview release	Internet Explorer 8
OS	Microsoft Windows Mac OS System 7 to OS X (discontinued) Solaris and HP-UX (discontinued) Windows 3.1 to Me (discontinued)
License	Proprietary MS-EULA
Website	microsoft.com/ie 1 · 2 · 3 · 4 · 5 · 6 · 7 · 8

Windows Internet Explorer (formerly Microsoft Internet Explorer abbreviated MSIE), commonly abbreviated to IE, 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 has been the most widely used web browser since 1999, attaining a peak of about 95% usage share during 2002 and 2003 with IE5 and IE6 but steadily declining since, despite the introduction of IE7. Microsoft spent over $100 million a year^[1] in the late 1990s, with over 1,000 people working on IE by 1999.^[2]

The most recent stable release is version Internet Explorer 7, which is available as a free update for Windows XP Service Pack 2, and Windows Server 2003 with Service Pack 1 or later, Windows Vista, and Windows Server 2008. Internet Explorer 8 is under development and is slated for release in 2009. A beta version of Internet Explorer 8 is currently available for download from the Internet Explorer website.

[edit] History

Main article: History of Internet Explorer

The Internet Explorer project was started in the summer of 1994 by Thomas Reardon and subsequently led by Benjamin Slivka, leveraging source code from Spyglass, Inc. Mosaic, an early commercial web browser with formal ties to the pioneering NCSA Mosaic browser. In late 1994, Microsoft licensed Spyglass Mosaic for a quarterly fee plus a percentage of Microsoft's non-Windows revenues for the software. Although bearing a name similar to NCSA Mosaic, Spyglass Mosaic had used the NCSA Mosaic source code sparingly.^[3]

Internet Explorer was first released as part of the add-on package Plus! for Windows 95 in 1995. 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.

Other versions available since the late 1990s include an embedded OEM version called Internet Explorer for Windows CE (IE CE), which is available for WinCE based platforms and currently based on IE6. Internet Explorer for Pocket PC, later rebranded Internet Explorer Mobile for Windows Mobile was also developed, and remain in development alongside the more advanced desktop versions.

[edit] Release history

Main article: Internet Explorer versions

Service packs are not included unless significant.

[edit] Features

Internet Explorer has been designed to view a broad range of web pages and to provide certain features within the operating system, including Microsoft Update. During the heyday of the historic browser wars, Internet Explorer superseded Netscape only when it caught up technologically to support the progressive features of the time.^[5]

[edit] Standards support

Internet Explorer, using the Trident layout engine:

• fully supports HTML 4.01, CSS Level 1, 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.
• partially supports CSS Level 2 and DOM Level 2, with major implementation gaps and conformance issues. Full conformance to the CSS 2.1 specification is on the agenda for the final Internet Explorer 8 release.^[6].
• does not support XHTML, though it can render XHTML documents authored with HTML compatibility principles and served with a text/html MIME-type.
• does not support SVG, neither for current version 7.0, nor for upcoming 8.0 version^[7].

Internet Explorer uses DOCTYPE sniffing to choose between "quirks mode" (renders similarly to older versions of MSIE) and standards mode (renders closer to W3C's specifications) 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 has been subjected to criticism over its limited support for open web standards and a major goal of Internet Explorer 8 is to improve support for such standards^{[citation needed]}.

[edit] Standards 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 can only be viewed properly using Internet Explorer.

Internet Explorer has introduced a number of extensions to JScript which have been adopted by other browsers. These include the innerHTML property, which returns the HTML string within an element; the XMLHttpRequest object, which allows the sending of ly 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.

A CNN article noted at the release of Internet Explorer 4: "Microsoft's Internet Explorer has made inroads and various estimates put its share of the browser market 30 to 35 percent from about 10 percent a year ago."^[17] By 2002, Internet Explorer had almost completely superseded its main rival Netscape and dominated the market with up to 95 percent market share.

After having fought and won the browser wars of the late 1990s, Internet Explorer gained almost total dominance of the browser market. Having attained a peak of about 95% during 2002 and 2003, its market share has since declined at a slow but steady pace. This is mainly due to the adoption of Mozilla Firefox, which statistics indicate is currently the most significant competition. Nevertheless, Internet Explorer remains the dominant web browser, with a global usage share of around 75% (though measurements vary). Usage is higher in Asia and lower in Europe.

Firefox 1.0 had surpassed Internet Explorer 5 in early 2005 with Firefox 1.0 at roughly 8 percent market share.^[19] An article notes at the release of Internet Explorer 7 in October 2006 that "IE6 had the lion's share of the browser market with 77.22%. Internet Explorer 7 had climbed to 3.18%, while Firefox 2.0 was at 0.69%."^[20]

Internet Explorer 7 was released at the same time as Firefox 2.0, and overtook Firefox 1.x by November 2006, at roughly 9% market share. ^[21] Firefox 2.0 had overtaken 1.x by January 2007, ^[22], but IE7 did not surpass IE6 until December 2007. ^[23] By January 2008, their respective version market share stood at 43% IE7, 32% IE6, 16% FF2, 4% SF 3, and both FF1.x and IE5 versions at less than half a percent. ^[24]

[edit] Market share by year and version

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. ^{[25][26][27][28][29][30]}

[edit] Industry adoption

The ActiveX extension mechanism is used by many public websites and web applications, including eBay. Similarly, 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.

[edit] Removal

Main article: Removal of Internet Explorer

While a major upgrade of Internet Explorer can be uninstalled in a traditional way if the user has saved the original application files for uninstallation, 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. Critics^{[citation needed]} felt that users should have the right to uninstall Internet Explorer freely just like any other application software. One of Microsoft's arguments during the trial was that removing Internet Explorer from Windows may result in system instability.

The Australian computer scientist Shane Brooks demonstrated that Windows 98 could in fact run with Internet Explorer removed.^[31] Brooks went on to develop software designed to customize Windows versions by removing "undesired components", which is known as 98lite. He later created XPLite to support NT based operating systems. Both of these pieces of software can remove IE after the installation of the operating system.

There are methods for removing IE from a copy of the Windows install disc so it never touches the user's hard drive. A method developed by Fred Vorck^[32] involves the manual removal of IE from installation discs. His process has been automated as a feature of HFSLIP. nLite and HFSLIP are automated programs that allow users to exclude IE and many other Windows components from installation as desired. In some older versions of Windows and in Windows Fundamentals there is an option to install Internet Explorer.

Removing Internet Explorer does have a number of consequences. Some applications that depend on libraries installed by IE may fail to function, or have unexpected behaviors. Intuit's Quicken is a typical example, which depends heavily upon the HTML rendering components installed by the browser. The Windows help and support system will also not function due to the heavy reliance on HTML help files and components of IE. In versions of Windows before Vista, it is also not possible to run Microsoft's Windows Update or Microsoft Update with any other browser due to the service's implementation of an ActiveX control, which no other browser supports. In Windows Vista, Windows Update is implemented as a Control Panel applet.

[edit] References

[edit] See also

Microsoft portal

• List of feed aggregators
• Comparison of feed aggregators

[edit] External links

• Internet Explorer: Home Page
• 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
• List of vulnerabilities by SecurityFocus
• Secunia – Vulnerability Report – Microsoft Internet Explorer 6.x
• Secunia – Vulnerability Report – Microsoft Internet Explorer 7.x
• Drip — A utility to detect and measure IE's memory leaks.
• IE Leak Patterns — Microsoft's analysis of IE's memory leak problem.
• Internet Explorer Exploits
• Rendering problems in Internet Explorer
• How the web was almost won — Just how close did we come to a Net ruled by Microsoft? The "server wars" show a grim counterpart to the browser wars