Rxvt is a terminal emulator for the X Window System and is intended to represent a range of functions and therefore reduced memory efficient substitutes for " xterm". " Urxvt " (or " rxvt -unicode " ) is in turn a clone of " rxvt ", the internal processes all data in Unicode as opposed to the original. With the proliferation of Compiz and Beryl won " urxvt " new meaning, as it is compatible with the newly introduced transparency of X.