Windows, dual-screen devices and shells: Piecing together Microsoft's Chromebook-compete strategy

It's Microsoft codename-apalooza time. How do Lite, Centaurus, Pegasus, WCOS and now, Santorini, all fit into what seems to be Microsoft's evolving Chromebook-compete strategy? Read on.
Written by Mary Jo Foley, Senior Contributing Editor

Understandably, Chromebooks are making Microsoft nervous. Yet so far -- at least publicly-- Microsoft hasn't done much more than tout lower-cost Windows PCs in an attempt to head off their growth. That may change, however, if Microsoft ends up assembling a bunch of currently independent Windows efforts into a cohesive whole. 

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Codenames of many of the pieces of Microsoft's Chromebook-compete strategy have been circulating for a while now.

There's "Centaurus," the alleged Microsoft dual-screen small laptop-type device in development. (There's also "Pegasus," which may be the codename for Windows 10 laptops running Lite.) There's "Windows Lite," or just plain-old "Lite," which is believed to be a very simplified and stripped down version of Windows which may not be branded "Windows" as it looks very little like Windows. And there's the Windows Core Operating System (WCOS), which we Microsoft watchers believe to be the successor to Windows OneCore -- Microsoft's effort to make the core of Windows more modular so that it can be shared across Windows 10 devices. 

Credit: TechRepublic

New Windows 10 devices like Centaurus, Surface Hub 2 and HoloLens 2 are all expected to be running WCOS under the covers. (Whether Microsoft ever publicly acknowledges this is a different question.) Different "shells," specific to particular devices/experiences, plug into WCOS. Surface Hub 2 will be WCOS plus "Aruba," the Hub 2 shell, we've heard. HoloLens 2 will be WCOS plus the "Oasis" holographic shell. Centaurus could be WCOS plus a CentaurusOS shell. Or -- if Centuarus ends up running Windows Lite, maybe it will be WCOS plus the Lite shell.

I'm hearing the codename for this Windows Lite shell is "Santorini." Santorini is what will enable Windows to work on foldable and other dual-screen form factor devices. Windows Central reported today that they believe Santorini is the replacement codename for Windows Lite, but my contacts say Santorini is the Lite shell, specifically. In either case, Santorini and Lite seem to be related, according to the codename keepers.

My contacts say Centaurus is not inextricably linked to Windows Lite. Nor is Windows Lite the absolute must-have operating system for  Centaurus and Pegasus devices. These things could ship independently or not. I, like others, have heard Microsoft is looking for ways to make sure Win32 apps can run on WCOS devices without requiring them to be rebuilt as "Centennial" applications, which may mean containers/virtual machines will be involved in some way. If that's true, this means Windows Lite devices won't just be limited to Universal Windows Platform (UWP) applications, which is good, since that limitation has led to the failure of Windows 10 S, the "mode" of Windows 10 that only allows users to run UWP/Store apps

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There are a lot of moving pieces here. Maybe Microsoft will be ready to explain some of this at its Build 2019 developers conference in early May. But there's also the realistic possibility that Microsoft officials won't ever get into the nuts and bolts of WCOS and different Windows shells, given Microsoft's leadership is continuing to try to take the focus off Windows and instead get investors, developers and customers to only think about the intelligent cloud/intelligent edge.

In case it's not already clear, Microsoft officials are not talking about any of these codenames or unannounced form factors. This is just a codename fiend (me) trying to keep all these constantly-changing names straight without resorting to a spreadsheet.

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