#### In this tutorial we are going to discuss the Poisson distribution. When we measure the occurrences of an event over a certain period of time or distance, we are often left wondering if what we observe is surprising.

The **Poisson Distribution** helps us determine the likelihood of specific discrete outcomes based on a given historical average number of occurrences. For instance, we know that the average firefly lights up 7 times over the course of 20 seconds.

With this distribution we can determine the extent to which it will be out of the norm if it lights up only 4 times during that interval. Being able to spot unusual frequencies of recurring events will help us determine whether something is worrisome or not and if we should further investigate the problem.