The Negative Binomial distribution is a probability distribution used in statistics to model the number of failures before a specified number of successes occurs in a series of independent Bernoulli trials. It is particularly useful in scenarios where the number of successes is fixed, but the number of trials can vary. This distribution is characterized by two parameters: the number of successes required and the probability of success in each trial. It can be seen as a generalization of the Geometric distribution, which models the number of trials until the first success. The Negative Binomial is often applied in fields like biology, economics, and quality control.