Source : Free On-Line Dictionary of Computing

TrackPoint
     
         (Or "pointing stick", "nipple") A small knob found
        in the middle of some {keyboards} that works like a very short
        {isometric joystick}.  Pressing it toward or away from you or
        from side to side moves the {pointer} on the screen.  Ted
        Selker brought the concept of an in-keyboard pointing device
        to {IBM} in September 1987.  TrackPoint was introduced in 1992
        on the {IBM} {ThinkPad} and later on some {desktops}.
     
        It takes up virtually no extra room on the box or the work
        area and also requires minimal movement of the hands from the
        keyboard.
     
        Many imitations of highly variable quality appeared.  Pointing
        sticks have also been used in many other {notebook} brands,
        including {TI}, {HP}, {Compac}, {Dell}, but NOT {Toshiba} or
        {AST}.
     
        "TrackPoint" and "Trackpoint" are IBM trademarks.
     
        {(http://www.research.ibm.com/mathsci/cmc/trackpoint.htm)}.
     
        [INTERACT'90, North Holland Pub Co, pp. 700-706].
     
        (2003-06-26)