Probability is often a source of difficulty and anguish for students at both high school and undergraduate levels, because they don't know its importance and worth.The foundation of probability was laid down by two French mathematicians of the seventeenth century - Blaise Pascal and Pierre De Fermat in connection with gambling problems. Later on it was developed by Jakob Bernoulli, Abraham De Mover, and Pierre Simon Laplace (1706-1749). The modern concept of probability theory which consists of stating few axioms and rules resulting from these axioms, was developed during the twenties and thirties of this century.Probability theory has a wider pasture of application and is used to make sharp decisions in mathematics, management, operational research, sociology, astronomy, engineering, gambling, card games, psychology, physics and genetics where risk and ambiguity are involved.Perhaps by providing a concise insight into where these concepts came from, how they were revealed, and how their uses in the past relate to how they are presently used and taught may offer students with the extra understanding they need to put these concepts to use, whether as measuring procedures or as functions. With this better insight, one would be able to see the value in studying Probability instead of an isolated unit from the subject.This book aims to help the readers understand the amazing world of Probability, to enlighten them on how this subject have significance in real world problems.