It gives you a terminal. you can install whatever version of linux you want I think. I just installed Ubuntu from the Microsoft App store. You can also access the path of the linux directory from windows and vice versa, but I guess this is not recommended. 

You get a home directory, and can chose where to install programs like normal.

Combining it with VS Code running in Windows is working quite nicely for me - https://code.visualstudio.com/docs/remote/wsl