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Internet Explorer 8

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Template:Beta software

Windows Internet Explorer 8
Developer(s)Microsoft
Preview release
Beta 1 / March 5, 2008
Engine
  • MSHTML
Edit this at Wikidata
Operating systemMicrosoft Windows
TypeWeb browser and feed reader
LicenseProprietary EULA
WebsiteWindows Internet Explorer 8 Website

Windows Internet Explorer 8 (commonly abbreviated IE8) is the next version of Microsoft's Internet Explorer web browser. Beta 1 was released to the general public in March 2008. [1]

Security, ease of use, and improvements in in RSS, CSS, and Ajax support are Microsoft's priorities for IE8,[2][3] along with significantly better support of web standards than Internet Explorer 7. As a result of better standards compliance, IE8 will break compatibility with web pages that were designed around the bugs and quirks of IE7. To soften the impact of these compatibility issues, IE8 will enable web designers to turn off all breaking changes in IE8. When a special meta element or its corresponding HTTP header is included in a web page, IE8 will render that page exactly like IE7 would. Users can switch between the two modes with a single click and then restarting Internet Explorer.[4]

History

IE8 has been in development since August 2007 at the latest.[5] In February 2008, Microsoft sent out private invitations for IE8 Beta 1,[6] and in March 2008, released Beta 1 to the general public.[7]

Features

The first beta release of IE8, which was demonstrated at the MIX08 conference, contains many new features, including WebSlices and Activities.[4] Activities are contexual commands that allows a user to invoke an online service from any other page.[8] Actions such as selecting the text or other objects will give users access to the usable Activity services (such as blogging with the selected text, or viewing a map of a selected geographical location), which can then be invoked with the selected object. According to Microsoft, Activities make copying and pasting between web pages easier.[4] IE8 specifies an XML-based encoding which allows an web application or web service to be invoked as an Activity service. How the service will be invoked and for what categories of content it will show up in specified in the XML file.[9] WebSlices are snippets of the entire page that an user can subscribe to.[8] WebSlices will be automatically kept updated by the browser, and can be viewed directly from the Favorites bar, complete with graphics and visuals. Developers can mark parts of the pages as WebSlices, using the hAtom and hSlice microformat.

Other new features in IE8 includes a redesigned Favorites Bar, which can now host content such as WebSlices, web feeds as well as documents, in addition to website links. The phishing filter has been augmented with Safety Filter that prevents sites known to spread malware from loading. Users need to make an explicit choice to load a blocked site; however this feature can be disabled using Group Policy. A crash recovery mechanism has been incorporated; if the browser crashes, web pages being viewed are recovered when the browser is restarted.[8] Full-page zoom now reflows the text to remove the appearance of horizontal scrollbars on zooming.[10] For developers, IE8 includes tools that allow HTML, CSS and JavaScript debugging directly from the browser.[9]

Internet Explorer 8 includes performance improvements across the HTML parser, CSS engine, mark-up tree manipulation as well as the JScript runtime and the associated garbage collector. Circular Memory leaks, which resulted earlier due to inconsistent handling of JScript objects and DOM objects, have been alleviated.[9] For better security, IE8 uses the Loosely Coupled Internet Explorer (LCIE) architecture and runs the browser frame and tabs in separate processes. It also leads to higher performance and scalability.[10] Permissions for ActiveX controls have been made more granular - instead of enabling or disabling them globally, they can now be allowed on a per-site basis.[10]

Standards support

File:IE8 Acid3.png
IE8 Beta 1 fails 83 out of 100 tests in Acid3.

IE8 improves rendering of content authored to various web standards (like HTML, CSS and JavaScript) in standards mode.[11] Such changes might cause it to break compatibility as it behaves significantly differently compared to IE7.[12] In order to maintain backwards compatibility, sites can opt-into IE7-like handling of content by inserting a special meta element into the web page, that triggers the "IE7 standards mode" in the browser, using[11] 

<meta http-equiv="X-UA-Compatible" content="IE=7" />

While the behavior of the browser is unchanged from Internet Explorer 7 in "IE7 Standards Mode", in standards mode (the default IE8 rendering mode), IE8 supports Data: URIs, HTML object fallback, the abbr tag, CSS generated content and the display: table CSS rule, in addition to fixing a lot of CSS and HTML parsing bugs.[5] As a result, IE8 Beta 1 passes the Acid2 test in IE8 standards mode.[13][5] Also, the proprietary hasLayout property will be eliminated when using IE8 in IE8 standards mode.[14]

Compliance with the CSS 2.1 specification has been one of the main goals of Internet Explorer 8. In addition, it also supports some CSS3 features.[9] IE8 also partially supports CSS 2.1 Paged media (including the @page CSS rule and the left, right and first page selectors).[9] In addition, it also supports the DOM: Storage, Cross Document Messaging (XDM) and the Selectors APIs. IE8 also suports cross-domain communication via the XDomainRequest object, that exposes a programming model similar to XMLHTTPRequest.[9] IE8 features an enhanced and standardized DOM, that brings it in line with implementations in other browsers. Attributes and properties in DOM objects are now handled differently, and the behavior of the getAttribute, setAttribute and removeAttribute modifiers have been changed to match the behavior of other browsers.[9] Internet Explorer 8 also supports the Accessible Rich Internet Applications specification for enhanced accessibility in AJAX applications.[10]

Version targeting

Internet Explorer 8 features stricter adherence to web standards, which in cases is incompatible with the behavior exhibited by previous versions of Internet Explorer. As a result, pages coded to the behavior of the older versions will break in IE8. This would have been a repetition of the situation with IE7, which having fixed a lot of bugs from IE6, broke pages which used the IE6 bugs to work around its non-compliance.

To avoid this situation, Microsoft proposed Version Targeting whereby a page could be authored to a specific version of a browser using the X-UA-Compatible declaration either as a meta element or in the HTTP headers.[15] A browser with a newer version than what the page has been coded for would emulate the behavior of the older version so that the assumptions the page made about the browser's behavior holds true.

Microsoft proposed that a page with a doctype that triggers standards mode (or almost standards mode) in IE7 would by-default trigger IE7-like behavior (called "standards mode") in IE8 and future versions of IE. The new features of IE8, along with the breaking changes, could be enabled by explicitly using the X-UA-Compatible declaration to trigger what Microsoft called the "IE8 standards mode". Microsoft's reasoning was that by making the choice to opt for standards compliance explicit, pages that do not want the behavior will not trigger the IE8 standards mode.[15] IE8 standards mode could also be triggered by the HTML5 doctype. Doctypes that trigger quirks mode in IE7 will continue to do so in IE8.

The proposal was met with much controversy, with experts on web development taking both sides of the issue. Critics felt that defaulting to non-standard mode would promote using the quirky behavior of IE7. Some even considered that to be a monopolist attempt to hold on to the market share.[16] Other felt that tying pages to browser versions would greatly hinder progressive development as championed by web standards.[17] Faced with the criticism, Microsoft, on March 3, 2008 reverted to make IE8 standards mode (now called "standards mode") the default in IE8 (i.e., pages with doctypes that trigger standards mode in IE7 as well as newer doctypes).[11] Version targeting would still be present but now would be used to opt-out of progressive development and use the IE7 standards mode.

Releases

On March 5, 2008 the Internet Explorer 8 Beta 1 Readiness Tookit website and tools went live.[1]

IE8 White Papers

The release of IE8 Beta 1 Microsoft released a family of White papers on the software. [18]

References

  1. ^ a b c Internet Explorer 8 Readiness Toolkit
  2. ^ LaMonica, Martin (2007-05-03). "Microsoft hints at general plan for IE 8". CNET News.com. Retrieved 2008-03-11.
  3. ^ Reimer, Jeremy (2007-05-02). "Microsoft drops hints about Internet Explorer 8". ars technica. Retrieved 2007-05-02.
  4. ^ a b c Mary Jo Foley. "IE 8 to feature WebSlices, Activities". CNet Blogs. Retrieved 2007-03-05.
  5. ^ a b c "IE 8: On the Path to Web Standards Compliance - ACID 2 Test Pass Complete". Microsoft. 2007-12-19. Retrieved 2007-12-20.
  6. ^ Foley, Mary Jo (2008-02-23). "Private IE 8 beta 1 test build coming soon". ZDNet. Retrieved 2008-03-01.
  7. ^ Internet Explorer 8 Readiness Toolkit
  8. ^ a b c "New and exciting features". Microsoft. Retrieved 2008-03-05.
  9. ^ a b c d e f g "How do I make my site 'light up' with Internet Explorer 8?". Microsoft. Retrieved 2008-03-05.
  10. ^ a b c d "How do I keep my site and add-ons working with Internet Explorer 8?". Microsoft. Retrieved 2008-03-05.
  11. ^ a b c Hachamovitch, Dean (2008-03-03). "Microsoft's Interoperability Principles and IE8". MSDN Blogs. Retrieved 2008-03-03.
  12. ^ Gustafson, Aaron (2008-01-21). "Beyond DOCTYPE: Web Standards, Forward Compatibility, and IE8". A List Apart. Retrieved 2008-01-22.
  13. ^ "Internet Explorer 8 and Acid2 A Milestone". 2007-12-19. Retrieved 2007-12-19.
  14. ^ Mielke, Markus (2007-12-20). "RE: FW: IE Blog: Internet Explorer 8 and Acid2: A Milestone". W3C. Retrieved 2007-12-28.
  15. ^ a b Aaron Gustafson. "Beyond DOCTYPE: Web Standards, Forward Compatibility, and IE8". Retrieved 2007-03-05.
  16. ^ Håkon Wium Lie. "Acid2, Acid3, and the power of default". CNet news. Retrieved 2008-03-05.
  17. ^ Jeremy Kieth. "They Shoot Browsers, Don't They?". A List Apart. Retrieved 2007-03-05.
  18. ^ http://code.msdn.microsoft.com/ie8whitepapers MSDN IE8 White Papers


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