hideturtle --Command, no inputs. Abbreviation: ht
     This command applies only to the display turtle. It erases the
     display of the turtle itself from the screen, so that only the lines
     drawn when the turtle moves are visible. The display is faster when
     the turtle is hidden (only slightly faster on the Atari, but much
     faster on other terminals). Also, once a graphics program is
     debugged, it may be prettier to watch without the turtle visible.
     (Note: On the Tektronix display, the turtle is never visible, because
     the terminal cannot erase selectively.)