In statistics, correlation is a kind of statistical relationship between two random variables or bivariate data. Usually it refers to the degree to which a pair of variables are linearly related. In statistics, more general relationships between variables are called an association, the degree to which some of the variability of one variable can be accounted for by the other.
The presence of a correlation is not sufficient to infer the presence of a causal relationship (i.e., correlation does not imply causation).Furthermore, the concept of correlation is not the same as dependence: if two variables are independent, then they are uncorrelated, but the opposite is not necessarily true: even if two variables are uncorrelated, they might be dependent on each other.
