What is the meaning of Probability Distribution?

Probability Distribution is the mechanism which generates occurrences, observations, events, returns, and variability of returns or risk. A famous distribution is the Normal Distribution with its often cited "bell-shaped curve." It should be noted that many other distributions have bell-shaped curve appearances but do not necessarily behave in a normal manner. There are several statistical tests to compare and differentiate between seemingly similar curves but significantly different processes. Some probability distributions are: Bernoulli, Beta, Binomial, Cauchy, Chi Square, Exponential, F, Gamma, Geometric, Lognormal, Negative Binomial, Normal, Pascal, Poisson, t and Uniform.