µTorrent was designed with relatively basic system requirements in mind. µTorrent for Windows runs on Windows XP and newer.
The Mac client is compatible with Mac OS X 10.5 and newer. Mac users can download µTorrent here.
Users of other operating systems may be able to use µTorrent on their computers with the use of a special piece of software that allows the operating system to run Windows applications. Note that there are no guarantees of any kind that everything will work properly when µTorrent is used on alternative operating systems.