Microsoft MSFT is embracing the new generation of lightweight, faster browsers like Google’s Chrome with a new name and branding for its Project Spartan browser project. The newly christened Edge browser will be part of the new Office 10 suite of products and was unveiled today at the Microsoft Build developer conference in San Francisco.

Microsoft Edge will be the only browser running on Microsoft Windows 10 mobile, but users can download the Edge browser or Internet Explorer 11 for laptops, larger tablets, or desktop machines. It’s unclear if Edge will be available on other mobile platforms such as Google’s Android or Apple’s iOS.

The technology inside the Edge browser is fundamentally different from what’s running inside Internet Explorer, Microsoft’s legacy browser that has declined from about 50% of the market share in the second quarter of 2012 to about 46% share today, according to Net Applications. In that period of time, the world has gone more completely mobile and browsing habits have changed. We now expect the web browser to handle phone calls, run web extensions, and applications. As our expectations changed, Internet Explorer did not.

In part that’s because IE was hobbled by its own success. When your clients are big corporate customers and tech-averse individuals who hate upgrading to a new version of software, it’s difficult to introduce new technology that could adversely impact thousands of small businesses. But Microsoft can’t ignore its declining share anymore, especially on mobile devices, where Internet Explorer holds a paltry 2.5% share, according to Net Applications.

In a blog post from March, when Microsoft said it would focus on the Edge browser (then called Project Spartan), a program manager wrote:

Project Spartan is our future: it is the default browser for all Windows 10 customers and will provide unique user experiences including the ability to annotate on web pages, a distraction-free reading experience, and integration of Cortana for finding and doing things online faster. Web developers can expect Project Spartan’s new engine to be interoperable with the modern Web and remain “evergreen” with no document modes or compatibility views introduced going forward.

Basically, it’s a browser that sounds a lot like the ones most technologically-inclined people are used to. And those people are the developers and younger generation that Microsoft needs to court if it wants to stay relevant going forward. But large corporate customers, don’t panic—Internet Explorer isn’t going away. Microsoft will release IE 11 with some (unspecified) versions of Office 10 and will continue to support it going forward. But unless your audience is captive, pushing them to Internet Explorer isn’t going to win you any converts. And even if they are captive, it’s a pretty cruel thing to do.