Statistics are used to measure the frequency of a past event that repeats many times. Probability makes it possible to calculate in advance the frequency of the realization of a future event, to come, which has not yet taken place. The most frequently cited example to understand the difference between the two concepts is that of the coin thrown into the air. If it is not faked everyone knows that there is a one in two chance for each side to appear. This is a probability of 0.5 or 50% of the value. If this probability is not known, the coin should be thrown in the air and the result obtained must be noted each time. It is only after throwing the coin in the air at least a thousand times that we will realize that each side will have appeared five hundred times to more or less five times and therefore that the average appearance on each side is equal to about 0.5 or 50% , probability value calculated in advance. The power of probabilities therefore lies in avoiding having to throw a room in the air a thousand times.