Geometric distribution

In probability, the geometric distribution with probability of success ${\displaystyle p}$, written ${\displaystyle \operatorname {Geo} (p)}$,[1] is a discrete probability distribution defined on non-negative integers. It is used to model the number of trials needed to obtain a first success, where the probability of success of each trial is ${\displaystyle p}$.[2]

An example involving geometric distribution is the number of times a coin needs to be tossed in order to get the first head.

The geometric distribution is the discrete analogue of the exponential distribution.[3]