http://www.wired.com/2014/12/microsoft-spartan-browser/
Microsoft’s Windows 10 operating system will debut with an entirely new web browser code-named Spartan... it will be a “lightweight” browser that looks and feels more like the Google Chrome and Mozilla Firefox browsers.
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Spartan is expected to use several visual and technical elements seen in competitor browsers like Google's Chrome and Firefox. Features include plug-in extension support and a new tab layout design. Because its competitors tout their rendering speed and security feature advantages over Internet Explorer, the new Microsoft browser will also likely focus on those areas...
Internet Explorer, as a brand and product, is not expected to be completely dropped. An updated version, Internet Explorer 11, also will be installed in Windows 10 as a backwards-compatibility browsing alternative.