ProbSim is a probability experiment simulator. You can tag fish, flip coins, roll dice, spin spinners, and draw marbles from urns. Predict the probability of a certain outcome, and see whether or not your prediction is supported by the experimental results. ProbSim also challenges you to solve some tricky and easily misunderstood probability problems involving birthdays, game shows, envelopes, coins, hats, urns, and apparent paradoxes.