This is a product for which Microsoft previously charged $99. The new version is free. It allows you to run a UNIX shell and many UNIX utilities in Windows and access NFS shares on the network. Microsoft expects people to use this to make it easier to migrate from UNIX or Linux to Windows, but it can also be used to go the other way - (insert big grin here)! It is a very big download. You can order a CD but there is a shipping charge.