Today, along with the announcement of many Windows 10 features, Microsoft also announced a new web browser codenamed "Project Spartan," which is meant to replace Internet Explorer in Windows 10.
One of the main changes in this browser compared to IE is the rendering engine. Microsoft claimed it's a new rendering engine, although previous reports have said it's actually a clean fork of Trident, IE's old rendering engine. More details should come out later about whether this rendering engine has been rewritten from scratch, or whether it still uses some parts from Trident.
There have also been rumors that Project Spartan will bring native support for extensions, just like Chrome. In fact, Spartan may even be able to work with Chrome's own extensions. However, Microsoft didn't made any mention of this today, so it's unclear whether the rumors were false or whether Microsoft was not ready to share that feature right now.
Creating a new browser from scratch that has to support all the latest HTML5 specs as its basic requirement is a hard enough task, and Microsoft's Spartan team may not have had enough time to have the extension support ready by now. This feature may still show up by the time Windows 10 launches later this year.
Microsoft chose to focus on three main user-oriented features: stylus support, a Safari-like "reading mode," and Cortana integration.
Microsoft has been focusing on supporting active pens for its tablets since the early 2000s. It continued that tradition with its Surface Pro devices, and it now wants to make the pens a little more useful for regular users. The Spartan browser will allow users to notate on pages directly with the stylus, or they can just click anywhere and add a comment. You can also "freeze" the page (so changes on the page don't affect your note-taking) or take a "snip" of the page and then easily share it with someone else.
Apple introduced the reading mode in its Safari browser on both iOS and Mac OS X mainly as a way to remove the clutter and make reading some web pages a more enjoyable experience. This feature also has the side effect of hiding ads. Microsoft will add a similar feature to its new browser, which will also be able to automatically save the pages for offline reading.
Finally, Microsoft has integrated Cortana into the Spartan browser. This means you can use Cortana to ask for directions, she can track your flights and remind you about them, and she will generally try to be helpful when you're viewing certain types of web pages. You can even right-click on pages to ask Cortana something.
Microsoft will make this new Project Spartan browser for all of its Windows-based platforms, but it hasn't said anything about building it for other operating systems, as well. Even if Internet Explorer still has a rather significant market share on the desktop of 59 percent (according to Net Stats), Windows is not the only big platform anymore. Chrome commands a large market share as well, thanks largely to mobile. If Microsoft wants its new browser to be the most popular, then it may have no choice but to build it for other platforms, too, much like it's been doing with Office.