"...demonstrates how experiments with random data
converge toward the predictions of probability theory as more and more
experiments are run.
The panel above initially shows the bell-curve normal
distribution approximating the binomial distribution for
an experiment consisting of 32 coin flips. To see the the bell curve
for experiments with different numbers of flips, enter a value between
4 and 1024 in the "Flips/run" box and press Enter. For ..."
continue at the Fourmilab