Wubi is short for "Windows-based UBuntu Installer". It is an official Windows-based software installer for Ubuntu, which makes Ubuntu one of the few Linux OS's that you can install while logged on to Windows. As opposed to booting from the DVD Drive and booting from there.
While I was logged into windows xp, I mounted Ubunto 10.10 on a virtual drive, and ran Wubi, to install Ubuntu and Windows side-by-side.
by kyle.biddle November 21, 2010