Probability is a statistical measure used to express the chances and risks in real life happenings. The study of statistics starts with the probabilities involved in simple experiments like tossing a coin or throwing a die. Advanced methods involving probability are used in predicting Poll outcomes, future job requirements, testing the validity or effectiveness of new medicines and in production planning.

The probability of an event is a number between 0 to 1 which measures the chance of that event occurring. The likelihood of the occurrence of the event increases as the probability varies from 0 to 1. The probability of the occurrence of an impossible event is 0 and that of a certain to occur event is 1.

Probability Measure
Probabilities can be expressed as decimals, fractions or percents.