Internet Explorer

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Internet Explorer

Internet Explorer 6 under Windows XP
Maintainer: Microsoft, Spyglass
Stable release: 6.0 SP2  (August 25, 2004) [+/-]
Preview release: 7.0b1  (July 27, 2005) [+/-]
OS: Windows
Genre: Web browser, File browser
License:
Website: www.microsoft.com/.../ie/

Internet Explorer, abbreviated IE or MSIE, is a proprietary web browser made by Microsoft and currently available as part of Microsoft Windows. Internet Explorer is the most widely used web browser today, although since 2004 it has lost some usage share to other browsers. As of October 2005, IE's usage share is about 86% (see the market adoption section).

Internet Explorer is an integrated component of all current versions of Microsoft Windows. Microsoft has shipped Internet Explorer as the default browser in all versions of Microsoft Windows since Windows 95 OSR1. The last major upgrade to Internet Explorer, however, was only offered for Windows XP Service Pack 2. The beta version of Internet Explorer 7 for Windows XP SP2 has been available since July 27, 2005.

Internet Explorer had also been available as a separate, free-of-charge product for many older versions of Windows, and several other operating systems. For some time, Microsoft produced Internet Explorer for Mac and versions for use through the X Window System on Solaris and HP-UX. All of these versions have ceased active development, although Internet Explorer for Mac is still available for download.

Contents

History

Main article: History of Internet Explorer
Internet Explorer 1.0
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Internet Explorer 1.0

Internet Explorer is derived from Spyglass Mosaic, an early commercial web browser. In 1995, Spyglass Mosaic was licensed by Microsoft in an arrangement under which Spyglass would receive a quarterly fee plus a percentage of Microsoft's revenues for the software. Although bearing a name similar to NCSA Mosaic, which was the first widely used browser, Spyglass Mosaic was relatively unknown in its day and did not use any of the NCSA Mosaic source code [1].

Internet Explorer 3 was the first major browser with CSS support, and it could handle the PICS system for content metadata. The improvements were significant, compared to its main competitor at the time, Netscape Navigator.

The browser was not widely used until version 4, which was released in October 1997 and was integrated with the Windows 98 operating system. This integration, however, was subject to numerous criticisms (see United States v. Microsoft). Version 5, released in September 1998, was another significant release which supported bi-directional text, ruby characters, XML and XSL.

Version 6 was released on August 27, 2001, a few weeks before Windows XP. This version included DHTML enhancements, content restricted inline frames, and better support of CSS level 1, DOM level 1 and SMIL 2.0. The MSXML engine was also updated to version 3.0. Other new features included a new version of the IEAK, Media bar, MSN Messenger integration, fault collection, automatic image resizing, P3P, and a new look-and-feel which is in line with the style of Windows XP.

Internet Explorer 7 Beta 1
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Internet Explorer 7 Beta 1

On February 15, 2005, Microsoft Chairman Bill Gates announced a new browser version at the RSA Conference 2005 in San Francisco [2]. The new beta version has been released on July 27, 2005. Internet Explorer 7 will be available to Windows XP SP2 and later only, including Windows XP Professional x64 Edition and Windows Server 2003 SP1 [3]. The new version of Internet Explorer is intended to defend users from phishing as well as deceptive or malicious software, and will include important bug fixes and some enhancements to better support the web standards. The decision to update the browser occurred in the wake of a decline in the use of Internet Explorer for the first time (see the market adoption section). An updated beta 2 featuring improvements in HTML 4.01 and CSS 2 is expected to be released in the fourth quarter of 2005.

Features

Main article: Features of Internet Explorer

Internet Explorer has been designed to view the broadest range of web pages and to provide certain features within the operating system, including Windows Update. During the heydays of the historic browser wars, Internet Explorer superseded Netscape by supporting many of the progressive features of the time.

Component architecture

The Component Object Model (COM) technology is used extensively in Internet Explorer. It allows third parties to add functionalities via Browser Helper Objects (BHO); and allows websites to offer rich content via ActiveX. As these objects have the same privileges as the browser itself (in certain situations), this raised concern over security. This issue was addressed in Internet Explorer 6.0 Service Pack 2, which provides an Add-on Manager for controlling ActiveX controls and Browser Helper Objects.

Usability and accessibility

The pop-up blocker included in Windows XP SP2
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The pop-up blocker included in Windows XP SP2

Since it is tightly integrated with the operating system, 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.

The ability to block pop-up windows (unrequested windows created with JavaScript) was introduced with Internet Explorer 6.0, Service Pack 2.

Tabbed browsing, while not natively supported, can be added to Internet Explorer 6 by installing Microsoft's MSN Search Toolbar. According to a post in IEBlog, the browser will support tabbed browsing in version 7.0, and the Beta 1 version of IE 7 includes tabbed browsing.

Web Feeds support is built in version 7.0, users can read Web Feeds(RSS/Atom) without RSS Reader and it discovers web feeds automatically.

Security framework

Internet Explorer uses a zone-based security framework, which means that sites are grouped based upon certain conditions. It allows the restriction of broad areas of functionality, and also allows specific functions to be restricted.

Patches and updates to the browser are released periodically and made available through Windows Update website. Although security patches continue to be released for a range of platforms, most recent feature additions and security improvements are released for Windows XP only. A report in April 2005 showed that only 24% of corporate PCs had upgraded to XP SP2.

Standards support

Internet Explorer almost fully supports HTML 4.01, CSS Level 1, XML 1.0 and DOM Level 1, with minor implementation gaps. It partially supports CSS Level 2 and DOM Level 2, with some implementation gaps and conformance issues. It supports XHTML 1.0 to the extent that HTML 4.01 compatibility guidelines are followed. Internet Explorer uses DOCTYPE sniffing to choose between "quirks mode" (renders similarly to older versions of MSIE) and standards mode (renders strictly according to W3C's specifications) for HTML and CSS rendering. It fully supports XSLT 1.0 or the December 1998 Working Draft of XSL, depending on the version of MSXML (a dynamic link library) available. It also provides its own dialect of ECMAScript called JScript.

Internet Explorer supports a variety of graphics file formats, including GIF, JPEG and PNG. The long-waited support for PNG alpha channel was introduced in 7.0 Beta 1.

Proprietary 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. Many view this as an example of what is called "embrace, extend and extinguish" (EEE), a way to drive competitors out of business by forcing them to use proprietary technology that a company controls, resulting in vendor lock-in. Netscape Navigator up to version 4.7 was also responsible for massive proprietary extension of the core web standards, but was not criticized for it as much.

Criticisms

Main article: Criticisms of Internet Explorer

Internet Explorer is subject to a relatively high volume of criticism. Much of this criticism is related to concerns about security: A notable portion of the widespread promulgation, across the Internet, of spam, spyware, adware, and computer viruses is known to be facilitated, in part, by exploitable bugs and flaws in the security architecture of Internet Explorer. Furthermore, a notable number of users and security experts believe that Microsoft has not been sufficiently committed to fixing the browser's exploitable bugs in a timely manner, and has been ineffective in pushing those changes out to users. Several companies maintain databases of security vulnerabilities known to exist in Internet Explorer and for which no fixes have been published by Microsoft — as of June 2005, there are between 20 and 27 such vulnerabilities reported in Internet Explorer 6 for Windows XP SP2, and 146 in Internet Explorer 6 for Windows 2000 SP4.

Other criticisms, mostly coming from technically proficient users and developers of websites and browser-based software applications, concern Internet Explorer's support of open standards. Internet Explorer supports, to some degree, a number of standardized technologies, but has implementation gaps and conformance failures – some minor, some not – that have led to criticism from an increasing number of developers. The increase is attributable, in large part, to the fact that competing browsers that offer relatively thorough, standards-compliant implementations are becoming more widely used. Internet Explorer's ubiquity, in spite of its perceived inferiority in this area, frustrates developers who want to write cross-browser code.

See also: Common criticisms of Microsoft.

Market adoption

Usage share

Statistics reference: Usage share of web browsers
Usage share of Internet Explorer over time
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Usage share of Internet Explorer over time

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 4.0 with Windows 98 in 1998, the adoption was greatly accelerated: from 57.6% in 1998 to 86.08% in 2000. It was often credited for bringing the World Wide Web to newbies. This effect, however, has recently been dubbed the "Microsoft monoculture", by analogy to the problems associated with lack of biodiversity in an ecosystem. By 2002, Internet Explorer had almost completely superseded its main rival Netscape and dominated the market.

After having fought and won the browser wars of the late 1990s, Internet Explorer began to see its usage share shrink. Having attained a peak of about 95.4% in 2002, it has since been in a steady decline. Statistics indicate the current most significant competition comes from Gecko-based browsers, in particular Mozilla Firefox.

Nevertheless, Internet Explorer remains the dominant web browser. The rate of decline is slow, compared to that of Netscape. Different organizations reported different usage share figures, depending on their approaches and samples: web analysis company WebSideStory reported that IE had a 88.46% USA usage share (as of September 23, 2005); OneStat reported that IE had a 85.45% global usage share (as of November 2, 2005); NetApplications reported that IE has a 86.87% usage share (as of September, 2005); and Janco Associates, Inc. reported that IE had an 85.09% usage share (as of October 11, 2005).

Industry adoption

ActiveX is used by many public websites and web applications, including eBay. Similarly, BHOs are also used by many search engine companies and third parties for creating add-on that access their services, for example, search engine toolbar. Because of the use of COM, it is possible to include web browsing function in application. Hence, there are a number of Internet Explorer shells, and a number of application like RealPlayer (a media player) also used the Internet Explorer's web browsing module for viewing the World Wide Web within the applications.

"Standalone" Internet Explorer

While it is not officially possible to keep multiple versions of Internet Explorer on the same machine, some hackers (Joe Maddalone, Ryan Parman, et al.) successfully separated several versions of Internet Explorer making them standalone applications. These were referred as "standalone" IEs and included versions 3.0 to 5.5 SP2.

Microsoft has discontinued standalone installers for Internet Explorer to the general public. However, a blogger/web developer/programmer named Liew Cheon Fong has posted a procedure for downloading the complete install package.

Removal

Main article: Removal of Internet Explorer

The idea of removing Internet Explorer from a Windows system was first proposed during the antitrust case. Critics felt that user 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. At least one commentator supports this argument, and notes that removing Internet Explorer will also disable Windows Update, leaving the user without vital security updates to the operating system. However, an Australian computer scientist Shane Brooks later demonstrated that Windows 98 could in fact run with IE files removed [4]. Brooks went on to develop software designed to customize Windows by removing "undesired components", which is now known as 98lite/XPLite. Microsoft has claimed that the software did not remove all components of Internet Explorer, leaving many DLL files behind.

Footnotes

  1. ^  Memoirs From the Browser Wars, May 12, 2005.
  2. ^  Microsoft to abandon standalone IE, May 12, 2005.
  3. ^  Gates Highlights Progress on Security, Outlines Next Steps for Continued Innovation, May 12, 2005.
  4. ^  IE7 Platforms and Outlook Express, May 12, 2005.
  5. ^  U.S. v. Microsoft: Court's Findings of Fact, May 12, 2005.

References

See also

External links

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