The term “regression” has biological origins: the offspring of the parents regress towards the mean. For example, the children of tall parents tend to be shorter, i.e., closer to average height.
In general use, a regression equation contains a cause-and-effect relationship between a dependent variable (which we wish to forecast) and one or more explanatory (or independent) variables, some of which are considered causal factors in changing the behavior of the dependent variable. The method of least squares is widely used to estimate that relationship.
Much business forecasting relies on univariate methods (also called time series and