The experiment end with a summery of the results.  The numbers in the 100  small squares are the difference between the expected value (average) of the number of heads (50) and the actual number of heads.  The squares that are colored pink are further from the average than the tolerance defined by the program.  For example if you set the tolerance to 3 you will generally see more pink squares than if you pick the tolerance to be 4.

Using Statistical knowledge we can estimate the number of experiments that will fall within any given tolerance level.