A computer-generated graphic which tracks the trajectory of a delivery between the bowler and batsman, and shows the probable trajectory of the ball if it were not hindered by the batsman. Used in an official capacity by the third umpire to assess lbw decisions under the decision review system. Commentators use Hawk-Eye as a visual aide to assess bowlers' deliveries, and (in the days before the DRS) to assess lbw decisions.