Programming Windows: 10 (Premium)

Microsoft spent much of 2013 and 2014 correcting the mistakes of Windows 8 via a set of small but meaningful updates. But its best work was yet to come: the software giant would celebrate the 30th anniversary of its core desktop platform in 2015 with a new version, Windows 10, that would go on to be its longest-running and most successful yet.

Codenamed “Threshold,” Windows 10 was an explicit admission that Windows 8 was the wrong direction. Where Steven Sinofsky’s insular and divisive team had taken a bold but misguided bet on touch-first mobile interfaces, Terry Myerson set out to dismantle those mistakes as much as possible. Windows 10 would be desktop-focused, not touch-focused, and while traces of the touch-first mobile interfaces of the past were present, they were clearly secondary.

With Windows 10, the Start menu would come back and all applications, including so-called universal Windows apps, would run alongside each other in resizable windows on the desktop. And key Windows 8 user interfaces like the Charms and Switcher would disappear.

For application developers, Microsoft would evolve the mobile app platform that arrived with Windows 8, but it would rename it yet again---to the Universal Windows Platform, or UWP---and expand its availability beyond PCs, tablets, and phones to also include Internet of Things (IoT) gadgets, and the Xbox One videogame console. It was, Myerson would later claim, “Microsoft’s most comprehensive platform ever,” and it would be backed by a unified mobile app store and user interfaces that would be “tailored” for specific device types.

Microsoft formally announced Windows 10 at a small event in San Francisco on September 30, 2014.

“I think we’d all say that Windows was at a threshold,” Myerson said while opening the event in a nod to the product’s original codename. The “new Windows,” as he called it, could have been called Windows 9, of course, and the team had debated other names, including Windows One. But because it wasn’t an incremental release, and because Windows 10 would provide the underpinnings for so many different product categories, they felt justified skipping over 9. The fact that Apple had by that point been using the version 10 with its Mac operating system for over 12 years probably played a role too.

From a user interface perspective, Windows 10 would look and feel natural to the over one billion Windows users who were not stuck with Windows 8. It would be a good upgrade from either Windows 7 or 8.x, Microsoft said, but the big upgrades were all on the desktop side, with a new Task View interface, support for multiple (virtual desktops), and a new Snap Assist interface that would suggest apps to fill the remaining space on-screen if you snapped an app.

“The diversity of the Windows audience is finally addressed by Windows 10,” Microsoft’s Joe Belfiore said during the event. “We’re adapting the core user experien...