Microsoft loves Linux. And Open Source. That wasn’t always the case back then. From Ars Technica:
Microsoft today released its PowerShell scripting language and command-line shell as open source. The project joins .NET and the Chakra JavaScript engine as an MIT-licensed open source project hosted on GitHub. Alpha version prebuilt packages of the open source version are available for CentOS, Ubuntu, and OS X, in addition, of course, to Windows. Additional platforms are promised in the future.