# Discrete Random Variables

In this section, we'll continue learning about and working with random variables. We will study a particular type of random variable: **discrete random variables**. These types of variables arise in every kind of applied domain, such as medicine, education, manufacturing, and so on, and therefore it is extremely useful to know how to work with them. We will learn about perhaps the most important, and certainly one of the most commonly occurring, discrete distributions: the binomial distribution.

## Defining Discrete Random Variables

Discrete random variables are those that can take only a specific number of values (technically, a *countable* number of values). Often, the values they can take are specific integer values, although this is not necessary. For instance, if a random variable can take the set of values {1.25, 3.75, 9.15}, it would also be considered a discrete random variable. The two random variables we introduced in the previous section are examples...