What is Discrete Random Variable?

A random variable that can take only a certain specified set of individual possible values-for example, the positive integers 1, 2, 3, . . . For example, stock prices are discrete random variables, because they can only take on certain values, such as $10.00, $10.01 and $10.02 and not $10.005, since stocks have a minimum tick size of $0.01. By way of contrast, stock returns are continuous not discrete random variables, since a stock's return could be any number.