The term correlation is generally used to indicate the correspondence or reciprocal relationship that occurs between two or more things, ideas, people, among others.
While, in probability and statistics, the correlation is what will indicate the strength and the linear direction that is established between two random variables.
It is considered that two variables of a quantitative type show correlation with each other when the values of one of them vary systematically with respect to the homonymous values of the other.
For example, if we have two variables called A and B, the aforementioned correlation phenomenon will exist if when the values of A increase the values corresponding to B also do so and vice versa.
In any case, it is worth clarifying that the correlation that may occur between two variables will not by itself imply any type of causal relationship. The main component elements of a correlation of this type will be: force, meaning and form.