One of the open secrets of software development is that version 1.0 doesn't necessarily reflect the complete vision of its creators. You might need several further updates, and a thing as complex as Windows 10 definitely will. Microsoft announced that Windows 10 is getting its first big revision, though the company didn't call it 10.1 or Service Pack 1. There's no branding on this one at all. Under the hood, it's Version 1511 (OS Build 10586.3). Build 10586 has been available to Windows Insiders for several days (and Microsoft has opened that program up to more users), but regular users may not know what the new features are. Let's go over the highlights.

Reduced boot time

Microsoft pitches three major changes. First, the company claims that the new build will take nearly 30% less time to start up than Windows 7 would on the same device. Of course, that depends on what kinds of parts you have in your computer, but if the range goes that high, then most users should see a few seconds shaved off their boot time. (Alternatively, you can use sleep mode instead of shutting down. That uses a trickle of power and will wake your computer up right away -- but this method increases the drain on laptop batteries, so it's not for everyone.) Some Windows 10 users have previously reported faster boot times from updating their motherboard BIOS, but this can be tricky for hardware novices; do it incorrectly and you can potentially render your computer unable to boot.

Cortana

The second major change is an update to Cortana, which is a personal digital assistant like Siri or Google Now. (We've seen recently how she fares against the competition.) Cortana can now recognize stylus input, so it can take phone numbers, street addresses, and email addresses written in a document and use them to set up contacts and calendar events. Cortana is also now available in Japan, Australia, Canada, and India, with information specialized for each region.

Edge browser

Third, Microsoft Edge, the default Web browser in Windows 10, has acquired more features -- although compatibility with Firefox and Chrome add-ons is not yet one of them; that will probably come next year. The update includes features that we've seen in Insider builds: You can view a thumbnail preview of a tab when you hover a mouse pointer over it, and you can sync your bookmarks across Windows 10 devices. In addition, Edge has integrated a coupon notification system that activates when you browse a shortlist of websites such as Macy's, Staples, and Best Buy.

Windows 10 for business

Microsoft also says that the new version of Windows 10 is mature enough that the company can "confidently recommend" businesses start using it in volume. Some companies skipped Windows 8 for a variety of reasons, such as the more familiar interface of Windows 7 (which has mostly returned in Windows 10). Although you might expect Microsoft to make such a statement, there are concrete reasons to listen. The company has created business versions of Windows Update and the Windows Store, to streamline software deployment and allow finer control over system updates. There's also better integration of mobile device management and Azure Active Directory Join, which can put an employee's Windows 10 data and settings in the cloud, to be retrieved and synced later with another Windows 10 device.

Windows 10 on Xbox One

Lastly, the Xbox One console has been updated to run Windows 10, though it will look nothing like what desktop users are used to, and you can't install PC software or PC games on it. Dubbed the New Xbox One Experience, it features an overhaul of the interface for easier and speedier navigation, plus more integrated social tools.

You can also now play 100 Xbox 360 games on the Xbox One, a feature known as backwards compatibility, and we're told that this list will steadily grow longer. This conversion has to be done on a case-by-case basis, so we don't have a specific time frame or number of titles that Microsoft expects to eventually support. Some highly requested titles like Red Dead Redemption are not on the list, and some games may never be included, depending on how much processing power is required to simulate an Xbox 360 inside an Xbox One. But as before, you can stream Xbox One games to a Windows 10 PC, and that feature now includes Xbox 360 games that run on Xbox One. This means you can now record gameplay video and take game screenshots on your PC.

Windows 10 on Windows Phones

Windows 10 is also coming to some Windows Phones soon, but the company did not give a date or say which specific mobile devices would get it. Members of the Insider program currently have access to preview builds.

More Resources

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Tom is the senior editor covering Windows at Download.com.