Random Variable

A variable whose value is unknown and can be numerically expressed as the result of a statistical experiment.  There are two types of random variables:

Discrete Random Variable

A discrete random variable can take any finite value. It represents a number found by counting. For example, a discrete variable can be defined as the outcome of tossing a fair dice. The set of value that this variable can take is {1, 2, 3, 4, 5, 6} only.

Continuous Random Variable

A continuous random variable, on the other hand, can assume any value between the specified limit. For example, the temperature of a given city on a given date is a continuous random value. It can take any value, including decimals, generally within the limits which are defined by the maximum and minimum temperature for that city.