The arrival of Bash in Windows 10 took many people by surprise, but it opens up a number of opportunities including the ability to run GUI Linux apps. But it's about much more than just that. Microsoft wants people who are confused about the arrival of (deep breath...) Bash on Ubuntu on Windows to know of the potential, and has produced an explainer about the Windows Subsystem for Linux.
Microsoft's Deepu Thomas says that the subsystem was created by the Microsoft Windows Kernel team, and goes on to explain that this is much more than an interpretation layer or virtual machine. In fact, the Windows Subsystem for Linux was born from work carried out years ago for the NT kernel that was meant to bring POSIX and OS/2 support.