Who is this for?
This is primarily a tool for developers -- especially web developers and those who work on or with open source projects. This allows those who want/need to use Bash, common Linux tools (sed, awk, etc.) and many Linux-first tools (Ruby, Python, etc.) to use their toolchain on Windows.
Why would I use WSL rather than Linux in a VM?
WSL requires fewer resources (CPU, memory, and storage) than a full virtualized machine. WSL also allows you to run Linux command-line tools and apps alongside your Windows command-line, desktop and store apps, and to access your Windows files from within Linux. This enables you to use Windows apps and Linux command-line tools on the same set of files if you wish.
https://msdn.microsoft.com/en-us/commandline/wsl/faq
Üdv,
Marci