Comparison

  ply
  40 +                                                 * Deep Blue
     .
     .
     .
     |
     |
  14 +
     |
     |
  12 +
     |
     |
  10 +                                           * Deep Thought
     |                                      * Hitech
     |
   8 +                                  * Belle
     |                               * Belle          * Gary Kasparov
     |
   6 +                        * Belle               * Anatoly Karpov
     |                * Belle                         * Bobby Fischer
     |
   4 +
     |
     |
   2 +
     |
     |
   0 +____+____+____+____+____+____+____+____+____+____+____+____+____+
     0    1.0  1.2  1.4  1.6  1.8  2.0  2.2  2.4  2.6  2.8  3.0  3.2  3.4

	     U.S. Chess Federation Rating x 10^3