Correlation is a term used to describe the relationship between the variables in a multivariate data distribution. The relationship found in Bivariate data between the independent and dependent variable is called a simple relationship. A simple relationship in turn is categorized in terms of direction, strength and shape.

The direction based categorization of correlation is consists of two types.
1. Positive Correlation
2. Negative Correlation

If the independent and dependent variables vary in opposite directions, then their relationship is described as a negative correlation. This means as the value of one variable increases the value of the other will decrease and vice versa.

The Scatter plot drawn for the data set will display a pattern falling down from left to right. The slope of the fitting line or curve for the data set will be negative at any point on the line or curve.