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Why more PC gaming handhelds should ditch Windows for SteamOS
(arstechnica.com)
From Wikipedia, the free encyclopedia
Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
Community icon by Alpár-Etele Méder, licensed under CC BY 3.0
Microsoft have quite a bit of software that runs on Linux (PowerShell, VS Code, .NET, Azure tools, Intune / Endpoint Manager, even SQL Server) so it's understandable that they'd have documentation to explain it to their customers.
Yep, they run it themselves even. Previously their motto was "Linux is a Cancer" now they have embraced it and developed their own distro (CBL). With how everything is going WebApp these days, I can see a day when Windows will be linux based kernel.