Microsoft appears to be skipping Windows 9 entirely; the most recent version of the OS is Windows 8.1, which followed 2012's Windows 8.
Terry Myerson, head of Microsoft's operating systems division, announced Windows 10 during an event in San Francisco today. Windows 10 "will be our most comprehensive platform ever," said Myerson, and "will run on the broadest types of devices ever."
Windows 10 will deliver "one application platform," said Myerson, as the slide seen in the image below appeared behind him to display a variety of devices: a smartphone, a phablet, tablets and laptop computers, a desktop and a TV with an Xbox One Kinect below it. It's unclear if the TV is showing an Xbox One — perhaps with a future version of the console's dashboard — but tiles seen in the interface include one for Forza Horizon 2 as well as multiple ones for apps such as Netflix, Skype and the NFL on Xbox.
Today's Windows 10 unveiling event in San Francisco was geared toward the business audience, so Myerson also took some time to focus on the operating system's enterprise-friendly nature. Windows 10 will offer "a very novel approach of separating corporate and personal data across all devices," he said, and will allow users to customize the Windows Store within the OS.
Myerson then introduced Joe Belfiore, corporate vice president of Microsoft's Operating Systems Group, for a demo. Windows 10 will include the long-awaited return of the Start menu, although the menu itself will now include some of the live tiles from the "Modern" interface in Windows 8. According to Belfiore, the new Start menu "gives the familiarity of Windows 7 with some of the elements of Windows 8," so that Windows 7 users will "get a familiar experience on the devices they already have."
"We want all these Windows 7 users to have the sentiment that yesterday they were driving a first-generation Prius... and now with Windows 10 it's like a Tesla," said Belfiore. "They don't have to learn any new way to drive."
Windows 10 users will be able to resize the Start menu as well as the tiles within it, and the Start menu will include universal search that also brings in results from the internet. The OS will also allow for Snap mode, which debuted in Windows 7 and also appears on the Xbox One, to be used with both desktop and Modern, touch-focused apps.
"As users start using these apps they should just feel familiar and work in a way you'd expect with a mouse and keyboard," said Belfiore.
The taskbar in Windows 10 features a new button, Task view, that opens up a multitasking interface that The Verge reports is similar to Exposé in Mac OS X. Task view supports multiple desktops, each of which can be running multiple apps in its own separate area.
With Windows 10, Microsoft won't be completely going back on the touchscreen-focused elements that it introduced in Windows 8. "We have a massive amount of users who know Windows 7 well, and Windows 8 users who know touch well. We need something that works for both," said Belfiore. "We want to support those Windows 8 users who have touch machines and [are] getting a lot of benefit out of them."
So Windows 10 will retain the Charm bar, which still appears with a swipe from the right edge of the screen, although Belfiore expects the bar itself to change between now and when Windows 10 is released. A left-side swipe brings up Task view. Belfiore also gave a brief demo of a feature called Continuum, an interface designed for convertible devices (like laptops with touchscreens) that will switch on the fly between keyboard and touch input. You can see the demo in the video below.
"We're trying to be thoughtful about a UI that goes across all devices," said Belfiore.
Microsoft will launch a Windows Insider Program tomorrow with a Technical Preview build of Windows 10 for laptops and desktops, followed by the same for servers. The company will tweak the OS based on feedback from those Insiders. Myerson said that Microsoft will "start talking much more about the consumer story" with Windows 10 in early 2015. More details about universal apps will be revealed at the company's developer conference, Build, in April. And Windows 10 will be released after that in mid-2015.
Asked about the Windows 10 name in a Q&A following the presentation, Myerson said, "When you see the product in its fullness I think you will agree with us that it is a more appropriate name."
The new OS is being designed for screens from 4 inches to 80 inches, according to Myerson, so Windows 10 is also the next version of Microsoft's smartphone OS. Regarding rumors of special pricing for Windows 8 users — namely, that Windows 10 will be free for people upgrading from Windows 8 — Myerson demurred, and said that he and Belfiore only "want to talk about the overall product family" today.