DEFINITION of 'Normal Distribution'
A probability distribution that plots all of its values in a symmetrical fashion and most of the results are situated around the probability's mean. Values are equally likely to plot either above or below the mean. Grouping takes place at values that are close to the mean and then tails off symmetrically away from the mean.
Also known as a "Gaussian distribution" or "bell curve".
INVESTOPEDIA EXPLAINS 'Normal Distribution'
The normal distribution is the most common type of distribution, and is often found in stock market analysis. Given enough observations within a sample size, it is reasonable to make the assumption that returns follow a normally distributed pattern, but this assumption can be disproved.
As with any distribution, the distributions mean, skewness and kurtosis coefficients should be calculated in order to determine the type of distribution you may be dealing with.

Leptokurtic
A statistical distribution where the points along the Xaxis ... 
Platykurtic
A type of statistical distribution where the points along the ... 
Covariance
A measure of the degree to which returns on two risky assets ... 
Kurtosis
A statistical measure used to describe the distribution of observed ... 
Mean
The simple mathematical average of a set of two or more numbers. ... 
Skewness
Describe asymmetry from the normal distribution in a set of statistical ...

Markets
The Uses And Limits Of Volatility
Check out how the assumptions of theoretical risk models compare to actual market performance. 
Forex Education
Trading With Gaussian Models Of Statistics
The entire study of statistics originated from Gauss and allowed us to understand markets, prices and probabilities, among other applications. 
Options & Futures
An Introduction To Value at Risk (VAR)
Volatility is not the only way to measure risk. Learn about the "new science of risk management". 
Active Trading Fundamentals
How To Convert Value At Risk To Different Time Periods
Volatility is not the only way to measure risk. Learn about the "new science of risk management". 
Fundamental Analysis
A DisasterProtection Plan For Your Portfolio
If you can't predict the future, you'll need to plan ahead to protect your assets from the impact of major world events. 
Fundamental Analysis
Monte Carlo Simulation With GBM
Learn to predict future events through a series of random trials. 
Mutual Funds & ETFs
Stock Market Risk: Wagging The Tails
The bell curve is an excellent way to evaluate stock market risk over the long term. 
Economics
How A Limited Government Affects A Country's Finances
Countries with limited governments have fewer laws about what individuals and businesses can and canâ€™t do. What's the net result? 
Personal Finance
What is the average salary for an accountant?
Learn about the average salaries of various accounting positions, and see the difference that an accounting degree makes in attaining higher wages. 
Fundamental Analysis
Lognormal and Normal Distribution
When and why do you use lognormal distribution or normal distribution for analyzing securities? Lognormal for stocks, normal for portfolio returns.