Microsoft unveiled the beta version of Internet Explorer 9, which the company hopes will allow it to maintain its market-share lead against Mozilla Firefox and Google Chrome.

Microsoft claimed in a Sept. 15 presentation in San Francisco that Internet Explorer 9 provides the best performance on the Web, leveraging both HTML5 and Windows 7 to deliver rich content faster.

“The Web is about sites; the browser should be, too. People go to the Web for sites, not the browser; much as you go to your PC for apps, not Windows. Today, Websites are boxed in. The box is the browser,” Dean Hachamovitch, corporate vice president of Windows Internet Explorer, explained to the audience during the presentation. “We asked ourselves: how could we put sites at the center of the experience? How can IE make sites shine. Our approach here is to use the whole PC.”

New browser features include the ability to tag tabs into Windows 7’s taskbar, for later retrieving a Web page without having to start up the browser, and “JumpLists” that allow easy access to Website tasks such as creating and checking email messages, or reading updated news.

Internet Explorer 9 also reflects in some ways on Microsoft’s vision for the cloud, where traditional operating systems and localized hardware remain front-and-center in the user experience. The browser leverages the PC’s underlying hardware, most notably its graphics processor, for accelerated graphics and video. “It makes HD video smoother, colors truer, graphics clearer, and Websites more responsive,” reads a note on Microsoft’s new IE9 corporate Website. “Combined with our new JavaScript engine, the Web now performs like an application installed directly on your computer.”

Internet Explorer also operates in a holistic way with Windows 7, such as the aforementioned “pinning” of Web pages to the taskbar. Pinned sites offer added functionality when selected, including links and player controls. Microsoft’s “Chakra” JavaScript engine is designed to take advantage of most modern PCs’ multiple CPU processing cores.

Microsoft hopes that Internet Explorer 9’s greater speed, combined with features such as extensive support for HTML5, will allow the browser franchise to solidify its market-share lead. Analytics firm Net Applications estimated Internet Explorer’s July market-share at 60.74 percent, an increase from June’s 60.32 percent, followed by Firefox with 22.91 percent, Chrome with 7.16 percent, Safari with 5.09 percent, and Opera with 2.45 percent. Those other browsers, though, have gradually eaten into Internet Explorer’s market-share over time.

What matters in the end is whether Windows users look to Microsoft or elsewhere for their window to the web.