This is not a virtual machine, not an emulator, and technically not linux. This is a native linux like environment on windows, including BASH, the coreutils, vim and more. Brought to you by the wonderful people who brought us mingw. If you are a *nix person and HAVE to use windows I highly suggest you install this. With this Firefox, Opera, Pidgin, and many more cross platform apps you will start to feel to home in windows.
EDIT: You can get git for it here. msysgit