Microsoft

Internet Explorer 10 debuted on Windows 8, and until now was only available to people who bought into Microsoft's big Windows redo. That changes today, as Redmond rolls out IE 10 for Windows 7 (download).

The update brings enormous changes to the browser, and mostly for the better. Internet Explorer 10 is not only faster and more stable than the current IE for Windows 7, version 9, it's also far more standards-compliant.

"Gone are the days when developers aspire to build for the lowest common denominator. The way the Web becomes like an application is when you take advantage of the latest hardware. We've stopped the era of trying to maximize for aggregate browser share," Ryan Gavin, general manager for Internet Explorer at Microsoft, said in a phone conversation with CNET last week.

Basically, what Gavin is saying is that hardware advances have made much of the modern Web possible, but he also acknowledged the role of Web developers. "One of the things that we hear from developers is that the depth and support across IE 10 means less time testing and more time developing," he said.

So, Windows 7 gets the new IE10 Chakra and JavaScript engines; the Touch API innovations that help drive the browser on Windows 8; the security measures built into IE10 -- at least, the ones that are not dependent on Windows 8; location bar autocomplete; and an on-by-default Do Not Track header.

The standards that IE 10 adheres to are nothing to sneeze at. Microsoft claims that its labs have found the new version of the browser to be 20 percent faster on Windows 7 than IE 9, and it supports a veritable alphabet soup of HTML5 and CSS3 improvements -- 60 percent more standards-compliant than IE 9, says Microsoft. These include CSS Text Shadow; CSS 3D Transforms; CSS3 Transitions and Animations; CSS3 Gradient; SVG Filter Effects; HTML5 Forms; input controls; validation; Web sockets; HTML5 Sandboxing; Web workers; HTML5 App Cache; File Reader API; and HTML5 Drag-drop, among other backend improvements.

In short, modern HTML5 sites that run smoothly in IE 10 on Windows 8, or the latest browsers from Chrome and Firefox, will now work properly in IE 10 on Windows 7.

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IE 10 for Windows 7 also comes with support for Pointer Events, which may seem strange to some. Pointer Events allow developers to write Web sites and register elements on the Web page to be responsive to multiple simultaneous interactions -- to respond to touch. Even though there are very few Windows 7 computers that shipped with touch screens, Gavin said that this was an important improvement to ship in the Windows 7 version of IE 10. "It's more about getting the developer to not having to do anything special to support the mouse on Windows 7 devices," he said.

Gavin and Rob Mauceri, Internet Explorer's group program manager who was also on the phone, both agreed that touch interaction would drive browser innovation for some time. "Four or five months ago, nobody was talking about touching the web," said Mauceri. "But now you've got new devices like the Pixel where others are following our lead."

Gavin was optimistic about the workplace adoption of IE 10 on Windows 7. "We're in a really good spot with enterprises, where we've been able to offer the latest version of our browser in a relatively short time frame," he said.

However, that's unlikely to be as cut-and-dried as Microsoft would like, even with Microsoft's best-in-class enterprise management tools. Browser adoption momentum indicates that businesses will continue gravitating away from IE, since IE 10 is only available on Windows 7 and Windows 8. The highest version of Internet Explorer that will work on Windows Vista is IE 9, while Windows XP users won't be able to graduate past IE 8.

One thing businesses won't have to worry about is whether Internet Explorer will adopt the six-week, rapid-release cycle of Chrome and Firefox. "We put less emphasis on release schedule and more emphasis on innovation. [Our] release schedule is a by-product of when that innovation is ready to go to market," said Mauceri.

There's little doubt that Internet Explorer 10 is the first version of IE in some time to ship with a fighting chance of being compared favorably to its competition. Being on Windows 7 is a massive boon to IE 10, but its inability to work on older operating systems that its competitors can comfortably perform on will hamstring it until those systems have significantly lower market share.

Correction, 11:03 a.m. PT: This story originally misspelled Rob Mauceri's last name.