Internet Explorer

2007 Schools Wikipedia Selection. Related subjects: Software

Windows Internet Explorer
Main Wikipedia page using Internet Explorer 7 running Windows XP
Developer:	Microsoft
Latest release:	7.0.5730.11 / October 18, 2006
OS:	Windows Mac OS X (up to version 5.2.3) Mac OS (up to version 5.1) Solaris and HP-UX (up to version 5.0)
Use:	Web browser
License:	Proprietary
Website:	Internet Explorer

Windows Internet Explorer, previously Microsoft Internet Explorer, abbreviated IE, or MSIE, is a graphical web browser developed by Microsoft and included as part of the Microsoft Windows line of operating systems. It has been the most widely used web browser since 1999.

Though released in 1995 as part of the initial OEM release of Windows 95, Internet Explorer was not included in the first retail, or shrink-wrap, release of Windows 95. The most recent release is version 7.0, which is available as a free update for Windows XP with Service Pack 2, and Windows Server 2003 with Service Pack 1. It is also included in the upcoming Windows Vista operating system. Versions of Internet Explorer prior to 6.0 SP2 are also available as a separate download for versions of Windows prior to Windows XP. There is a version for Windows CE and Mobile called Pocket Internet Explorer.

After the first release for Windows 95, additional versions of Internet Explorer were developed for other operating systems: Internet Explorer for Mac and Internet Explorer for UNIX (the latter for use through the X Window System on Solaris and HP-UX). Only the Windows version remains in active development; the Mac OS X version is no longer supported.

History

Internet Explorer was originally derived primarily from Spyglass Mosaic, an early commercial web browser. In 1995, Microsoft licensed Spyglass Mosaic from Spyglass for 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 used the NCSA Mosaic source code only sparingly.

Internet Explorer was not widely used until the release of version 3, which was the first version developed without Spyglass sources (although still using Spyglass "technology", so the Spyglass licensing information remained in the program's documentation). Internet Explorer 4 was the first version integrated into Windows Explorer and other core parts of Windows. The integration with Windows, however, was subject to numerous criticisms (see United States v. Microsoft).

Internet Explorer 3 was the first major browser with CSS support. Released on August 13, 1996, it introduced support for ActiveX controls, Java applets, inline multimedia, and the PICS system for content metadata. These improvements were significant, compared to its main competitor at the time, Netscape Navigator. Version 3 also came bundled with Internet Mail and News, NetMeeting, and an early version of the Windows Address Book, and was itself included with Windows 95 OSR 2. Version 3 proved to be the first popular version of Internet Explorer, which brought with it increased scrutiny. In the months following its release, a number of security and privacy vulnerabilities were found by researchers and hackers.

Version 4, released in September 1997, deepened the level of integration between the web browser and the underlying operating system. Installing version 4 on a Windows 95 or windows NT 4 machine and choosing "windows desktop update" would result in the traditional Windows Explorer being replaced by a version more akin to a web browser interface, as well as the Windows desktop itself being web-enabled via Active Desktop. This option was no longer available with the installers for later versions of Internet Explorer but was not removed from the system if already installed. Internet Explorer 4 introduced support for Group Policy, allowing companies to configure and lock down many aspects of the browser's configuration. Internet Mail and News was replaced with Outlook Express, and Microsoft Chat and an improved NetMeeting were also included. This version also was included with Windows 98.

Version 5, launched on March 18, 1999, and subsequently included with Windows 98 Second Edition and bundled with Office 2000, was another significant release that supported bi-directional text, ruby characters, XML, XSL and the ability to save web pages in MHTML format. (Windows 2000 included Internet Explorer 5.01 instead.) Version 5.5 followed in July 2000, improving its print preview capabilities, CSS and HTML standards support, and developer APIs; this version was bundled with Windows Me.

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, Windows Messenger integration, fault collection, automatic image resizing, P3P, and a new look-and-feel that was in line with the "Luna" visual style of Windows XP.

On February 15, 2005, Microsoft Chairman Bill Gates announced that the new version of its browser would be released at the RSA Conference 2005 in San Francisco. The decision to update the browser occurred in the wake of a decline in the use of Internet Explorer for the first time. Microsoft also stated that Internet Explorer 7 is available only for Windows XP SP2 and later, including Windows Server 2003 SP1 and Windows Vista. The first beta version of the browser was released on July 27, 2005 for technical testing, and a first public preview version of Internet Explorer 7 (Beta 2 preview: Pre-Beta 2 version) was released on January 31, 2006. The final public version was released on October 18, 2006. Version 7 is intended to defend users from phishing as well as deceptive or malicious software, and also features full user control of ActiveX, and better security framework. It includes important bug fixes, enhancements to support the web standards, improvements in HTML 4.01/CSS 2, Tabbed Browsing, Tab preview and management, and web feeds reader. It is also to be noted this is the first version of Internet Explorer not to be based upon Spyglass technologies.

Features

Internet Explorer has been designed to view the broadest range of web pages and to provide certain features within the operating system, including Microsoft 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 functionality via Browser Helper Objects (BHO); and allows websites to offer rich content via ActiveX. As these objects can have the same privileges as the browser itself (in certain situations), there is a concern over security. This issue was addressed in Internet Explorer 6.0 SV1, which provides an Add-on Manager for controlling ActiveX controls and Browser Helper Objects. Internet Explorer 7 provides a "No Add-Ons" version (Under Programs/Accessories/System Tools) to address this issue, as well.

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 (although this feature now requires a shell window to be opened as of version 7, rather than natively within the browser). VBA is not supported, but available via extension (iMacros).

The ability to block popup windows was introduced with Internet Explorer 6.0, Service Pack 2.

Tabbed browsing can be added to Internet Explorer 6 by installing Microsoft's MSN Search Toolbar, and is natively supported as of Internet Explorer 7.

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 the Windows Update service, as well as through Automatic Updates. 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.

Internet Explorer 6 Service Pack 2 provides Download Monitoring and Install Monitoring allowing users the choice of whether or not to download and install executables, in two stages. This helps to prevent installation of malware. Executable files downloaded using Internet Explorer are marked by the operating system as being potentially unsafe, and will prompt the user to confirm they want to run the executable every time, until the user confirms the file is "safe".

Group

Internet Explorer is fully configurable using Group Policy. Administrators of Windows Server domains can apply and enforce a variety of settings 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 on a per-user and per-machine basis.

Standards support

Internet Explorer, using the Trident layout engine, 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. XML support brings with it support for XHTML, however Microsoft has buried this support since IE 5.0 making it difficult to access. Like other browsers it can consume XHTML when served as MIME type “text/html”. It can also consume XHTML as XML when served as MIME types “application/xml” and “text/xml”, however this requires a small XSLT measure to re-enable the XHTML as XML support. It pretends to not comprehend XHTML when vended in the preferred type as “application/xhtml+xml” and instead treats it as an unfamiliar file type for download.

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 (for printing Internet Explorer always uses standards mode). 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.

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.

Version 7

Version 7.0 of Internet Explorer has been renamed Windows Internet Explorer, as part of Microsoft's rebranding of component names that are included with Windows. It is available as part of Windows Vista, and as a separate download via Microsoft Update for Windows XP with Service Pack 2 and Windows Server 2003 Service Pack 1. Internet Explorer 7 can also be downloaded directly from Microsoft's website. Large amounts of the underlying architecture, including the rendering engine and security framework, have been completely overhauled. Partly as a result of security enhancements, the browser will be a stand-alone application, rather than integrated with the Windows shell, and it will no longer be capable of acting as a file browser. The first security advisory was posted only one day after the day of release., but it turned out to be a security problem in Outlook Express, not in Internet Explorer 7.

IE7 in Windows Vista incorporates additional security measures, most significantly "Protected Mode", whereby the browser runs in a sandbox with even lower rights than a limited user account. As such, it can only write to the Temporary Internet Files folder and cannot install start-up programs or change any configuration of the operating system without communicating through a broker process. This is expected to increase the security of the system considerably. The Windows XP version of Internet Explorer 7 will not include "Protected Mode" operation, as it relies on technologies not found on systems before Vista. It also supports the Parental Controls and Network Diagnostics features which are unique to Vista. Internet Explorer 7 has only been released for Windows XP and later operating systems.

Release history

• On January 31, 2006, Microsoft released a public preview build ( Beta 2 preview: Pre-Beta 2 version) of Internet Explorer 7 for Windows XP Service Pack 2 (not for Windows Server 2003 SP 1) on their web site. It stated that more public preview builds (possibly Beta 2 in April) of Internet Explorer 7 will be released in first half of 2006, and final version will be released in second half of 2006. The pre beta build was refreshed on March 20, 2006 to build 7.0.5335.5. A real Beta 2 Build was released on April 24, 2006 to build 7.0.5346.5. In addition, at the MIX'06 conference, Bill Gates said that Microsoft is already working on the next two versions of IE after version 7.
• On June 29, 2006, Microsoft released Beta 3 (Build 7.0.5450.4) of Internet Explorer 7 for Windows XP SP2, Windows XP x64 Edition and Windows Server 2003 SP1. It features minor UI cleanups, re-ordering of tabs by drag and drop, as well as noticeable performance improvements.
• On August 24, 2006, the Release Candidate 1 (RC1) of Internet Explorer 7 (Build 7.0.5700.6) was released for Windows XP SP2, Windows XP x64 Edition and Windows Server 2003 SP1. This was the last pre-release version of IE7 before the final release.
• On September 28, 2006, 3Sharp, a privately held technical services firm, published the results of a study, commissioned by Microsoft, evaluating eight anti-phishing solutions in which Internet Explorer 7 (Beta 3) came out on top. The study evaluated the ability to block phish, to warn about phish, and to allow good sites.
• On October 18, 2006 the final version was released on microsoft.com, and was distributed as a high-priority update via Automatic Updates (AU) on November 1. AU notifies users when IE7 is ready to install and shows a welcome screen that presents key features and choices to “Install”, “Don’t Install”, or “Ask Me Later”.

New features and changes

• For better security, Internet Explorer is no longer integrated with the Windows Explorer shell. Local files typed in IE7 are opened using the Windows Explorer shell and websites typed in Windows Explorer shell are opened using the default web browser.
• Protected Mode (available in Windows Vista only), whereby the browser runs in a sandbox with even lower rights than a limited user account. As such, it can only write to the Temporary Internet Files folder and cannot install start-up programs or change any configuration of the operating system without communicating through a broker process. IE7 Protected Mode relays on UAC
• Version 7 supports tabbed browsing, a popular feature in competing web browsers. Also new is a feature called "Quick Tabs", which displays a thumbnail preview of opened tabs. Since the release of Beta 3 onwards, the user has been able to manually rearrange the tabs by dragging and dropping them as desired.
• Version 7 adds support for internationalized domain names (IDN) with included anti-spoofing protection. If the user visits a website whose name is in a foreign language (non-Latin characters), it will be displayed in punycode if the user does not have support for the language installed. Also, non-Latin characters can, with certain restrictions, be mixed with Latin characters. In the latter case, punycode is used if support for the non-Latin script is not installed. This helps prevent phishing scams, where some characters are replaced with a similar looking character from a different alphabet.
• A search box has been added to the top-right corner. The default search engine is inherited from Internet Explorer 6's settings, which various search engine toolbars override to provide search capabilities on the address bar, but additional providers may be added (Google, Altavista, Yahoo!, Windows Live Search, Wikipedia, etc). Microsoft supplies a list of common providers. The search box uses A9.com's OpenSearch technology to import search providers. By using an open standard, Microsoft made it easier for websites to include their pre-defined search queries in the search box. Also available is a comprehensive list of popular search providers that can be added to the search box. With the release of Windows Internet Explorer 7, Microsoft updated its list of common providers with a tool that enables users to manually create and add a search provider to the search box.
• Support for per-pixel alpha channel transparency in PNG images has been added.
• A fully integrated feed reader is included, so that users can read web feeds (RSS or Atom) without a separate RSS reader. Features include automatic feed discovery and the ability to retrieve feed updates even when the web browser isn't running. The web feeds feature set is also available to third-party developers through API's, so that the list of subscribed feeds (as well as their current contents) can be used.
• ActiveX Opt-In blocks ActiveX Control unless it allowed to be installed. This feature improves security from unverifiable and vulnerable controls. ActiveX controls can be chosen to be installed on Information Bar. User can turn on and off ActiveX Control by using Add-on Manager.
• A number of improvements to CSS, DOM, and HTML support have been made. Microsoft's stated goal with version 7 was to fix the most significant bugs and areas which caused the most trouble for developers, and then improved coverage of the standards would come later.
• The well-known problem of having the right-hand portion of a web page cut off when the page is printed has been fixed. Page content can also be "shrunk" to fit more text on a single page. The revamped "Print Preview" interface will also let users drag the page margins around and see the results immediately.
• A Page Zoom selector has been added to the bottom-right corner of the user interface. Unlike the "Text size" feature, this will zoom the complete contents of the web page, allowing for easier reading on larger displays. Fonts are rendered at higher resolution.
• ClearType can be enabled or disabled separately from the rest of the operating system.
• The new Phishing Filter offers protection against phishing scams and other websites that may be considered dangerous for a user to enter their personal information into. When enabled, every website the user visits is checked against a master list of known phishing sites. If a site is listed, the user is informed. In light of the privacy implications of this feature, it is not enabled automatically; the user is asked when they start Internet Explorer 7 if they want it enabled. Microsoft is working in conjunction with companies that specialize in identifying phishing schemes to ensure the list of known sites is accurate and quickly updated.
• The address bar and status bar appear in all windows including popups which helps to block malicious sites from disguising them as trusted sites. Also the address bar features a colour code to visually indicate the trustworthiness of the page. The address bar turns red when a page, with invalid security certificate, is accessed. In case of sites not using any encryption, the address bar is white. And if the page uses high security certificate, the bar turns green.
• Modal windows such as dialog boxes are shown only when the tab that has generated them is selected (in such situations, the tab colour becomes orange).
• The address bar no-longer allows JavaScript to be executed on blank pages (about:blank). This feature is still supported on other pages though, which enables bookmarklets to work properly. A reason for the change has not been given.
• The status bar no-longer allows custom text to be entered (e.g.: "Formatting C:\ 10% Complete |||||||") and will always show the URL of any link hovered over, for security.
• "Delete Browsing History" cleans the complete browsing history in a single step. Previously this was a multistage process requiring users to delete browser cache, history, cookies, saved form data and passwords in a series of different steps. This is useful for improving privacy and security in a multiuser environment, such as an Internet café.
• Contextual Go/Refresh button. When any URL is typed into the address bar, the button changes from "Refresh" to "Go" and when "Go" (or keyboard Enter) is hit, the button changes from "Go" to "Refresh". In this way the space taken by the toolbars is minimized.
• The "back" and "forward" menus have been combined into one menu which shows the users current position in their history with a bold entry. In most cases, the current page will be at the top, with a list of pages to go "back" to, but if the user has just gone back one or more pages, there will be additional items above the current page to which they can navigate forwards.
• Fix My Settings checks at startup or when a setting is changed, if the current settings are unsafe it notifies the user. The user can also press a button in order to fix the settings to a safe state.
• Old protocols and technologies removed: Gopher, TELNET, Scriptlets, DirectAnimation, XBM, Channels (.CDF files) also known as ' Active Desktop Items', etc. The DHTML Editing Control is being removed from IE7 for Windows Vista to reduce surface area for security attacks.
• No Add-ons allows IE7 to launch without the installed extensions.
• The menu bar can be hidden to allow more space for webpages.
• Improved text selection.
• IE7 cipher strength: 256-bit (Only for Vista, IE7 for XP only supports 128-bit)
• New Group Policy's Administrative Templates (.adm files) for IE7 are loaded automatically onto the Domain Controller when a Group Policy is opened from a workstation where IE7 has been installed. These new administrative templates allow for controlling the Anti-Phishing filter state, for example.
• Reset Internet Explorer settings is useful if your browser is in an unusable state: deletes all temporary files, disables browser add-ons, and resets all the changed settings.

Criticism

Security

Much criticism of Internet Explorer is related to concerns about security: 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 download": an attempt to trick the user into installing malicious software by misrepresenting the software's true purpose in the description section of an ActiveX security alert.

While Internet Explorer is not alone in having exploitable vulnerabilities, its ubiquity has resulted in many more affected computers when vulnerabilities are found. Microsoft has not responded as quickly as competitors in fixing security holes and making patches available. Not only are there more security holes discovered in Internet Explorer, but these vulnerabilities tend to remain unpatched for a much longer time, in some cases giving malicious web site operators months to exploit them before Microsoft releases a patch. Several companies maintain databases of known security vulnerabilities that exist in Internet Explorer, for which no fixes have been published by Microsoft. As of November 27, 2006, Secunia reports 3 unpatched vulnerabilities in Internet Explorer, of which the most severe vulnerability is rated "moderately critical". In contrast, Mozilla Firefox, the main competitor to Internet Explorer, is reported to have 1 unpatched security vulnerability, rated "less critical." Opera, another competitor to Internet Explorer, is also reported to have no unpatched security vulnerabilities.

In May 2006, PC World rated Internet Explorer 6 the eighth worst tech product of all time.

Standards support

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, because the browser often uses proprietary extensions to achieve similar functionality.

Internet Explorer supports, to some degree, a number of standardized technologies, but has numerous 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 inferiority in this area, frustrates developers who want to write standards-compliant, cross-browser code and the advanced functionality it provides, because they are often stuck coding pages around Internet Explorer's bugs, proprietary featureset, and missing standards support instead.

Web developers must work with the least advanced technology across all browsers they wish to support, and Internet Explorer is often criticized for being technically obsolete. These include poor CSS support and no native XHTML support: both of which remain serious problems in Internet Explorer 7. For another long-standing concrete example, see Internet Explorer's poor PNG transparency support, which remained unfixed until Internet Explorer 7.

Market adoption

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. 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 96% in 2002, it has since been in a small steady decline, likely 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 85% (based on statistics reference). Usage is higher in Asia and lower in Europe. For example, the share is around 94% in Japan, and around 56% in Germany.

Industry adoption

ActiveX 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, for example, search engine toolbars. Because of the use of COM, it is possible to include 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.

"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.

• Multiple IEs In Windows Web Design — The web developer Joe Maddalone who found the solution.
• Skyzyx.com - Standalone Internet Explorer — The web developer Ryan Parman who made the customized browsers files available.
• Multiple Explorers — Downloads of all the versions

Microsoft has discontinued standalone installers for Internet Explorer to the general public. However, there are unofficial procedures for downloading the complete install package. Internet Explorer standalone hacks exploit a known workaround to DLL hell, which was introduced in Windows 2000, called DLL redirection.

• Standalone Install Procedure for IE6 SP1

Unlike previous versions of Internet Explorer, running Internet Explorer 7.0 requires the presence of some keys in the Windows registry before starting. This is due to Microsoft Security Bulletin MS05-054 as mentioned in IEBlog.

• Jon Galloway's batch script for running IE7 — Supports the latest IE7 RC1.
• A standalone launch program for IE7 — Supports the latest IE7 RC1.

Yousif has provided a program available here which automates installation of standalone versions of Internet Explorer from 3.0 to 6.0. This allows you to install version 7 as the "default" version of Internet Explorer.

Manfred Staudinger has created an online guide/article detailing how to enable cookies and MS proprietary Conditional Comments, Here.

Removal

The idea of removing Internet Explorer from a Windows system was first proposed during the United States v. Microsoft case. Critics 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. 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. However, both of these pieces of software work, in part, by installing obsolete versions of components (such as Windows Explorer) required by the operating system to function.

There are a few popular 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 involves the manual removal of IE from installation discs. nLite, on the other hand, is an automated program that allows 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. It is also not possible to run Microsoft's Windows Update with any other browser due to the service's implementation of an ActiveX control, which no other browser supports. Another possibility is to use AutoPatcher, an unofficial and unauthorised update manager, which does not require the use of a web browser at all.